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广西医科大学. Computer Networking. 网络课件. 双语教学. 模拟实验. 计算机网络教研室. DI. 1. 2. 3. CHAPTER 3 Network Architetures and Standarts. The first section. Exercises. Online lecture. 3-7. 3-4. 3-1. 3-13. 3-10. A caveat about. Standards making org. Advs and disadvs of standards. - PowerPoint PPT Presentation

Citation preview

Page 1: Computer Networking

Computer Networking

网络课件 双语教学 模拟实验

广西医科大学

计算机网络教研室

>

Department of Computer Networking Application

CHAPTER 3 Network Architetures and Standarts

DI1 The first section

2 Exercises

3 Online lecture

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Introduction3-1

Definition Architecture3-2

Why have Architecture3-3 3-10

Definition Architecture3-5

The Vand Xstandards3-6

Advs and disadvs of standards3-7

Communication Architecture3-8

ISO Reference Model3-9

Standards making org3-4 Internet Architecture3-11

Manufactures Architecture3-12

A caveat about3-13

Layered architecture3-14

TCPIP Architecture

Network Management and Operation wwwgxmueducn

OBJECTIVESExplain the difference between architectures and standardsExplain the need for network architecture and standardsIdentify a number of communications standards-making orgDescribe the OSI model architectureDescribe TCPIP architectureDescribe the architecture of the InternetDiscuss the ADV and DISADV of layered architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

31 IntroductionDefinitions of architectures and standardsThe difference among themThe need of themSpecific example of themExamine adv amp disadv

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

32 DEFINITION OF ARCHITECTURES AND STANDARDS

Architecture is a plan or direction that is oriented toward the needs of the userNetwork architecture is a set of principles used as the basic for the design and implementation of a communications network

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 2: Computer Networking

Department of Computer Networking Application

CHAPTER 3 Network Architetures and Standarts

DI1 The first section

2 Exercises

3 Online lecture

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Introduction3-1

Definition Architecture3-2

Why have Architecture3-3 3-10

Definition Architecture3-5

The Vand Xstandards3-6

Advs and disadvs of standards3-7

Communication Architecture3-8

ISO Reference Model3-9

Standards making org3-4 Internet Architecture3-11

Manufactures Architecture3-12

A caveat about3-13

Layered architecture3-14

TCPIP Architecture

Network Management and Operation wwwgxmueducn

OBJECTIVESExplain the difference between architectures and standardsExplain the need for network architecture and standardsIdentify a number of communications standards-making orgDescribe the OSI model architectureDescribe TCPIP architectureDescribe the architecture of the InternetDiscuss the ADV and DISADV of layered architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

31 IntroductionDefinitions of architectures and standardsThe difference among themThe need of themSpecific example of themExamine adv amp disadv

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

32 DEFINITION OF ARCHITECTURES AND STANDARDS

Architecture is a plan or direction that is oriented toward the needs of the userNetwork architecture is a set of principles used as the basic for the design and implementation of a communications network

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

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A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 3: Computer Networking

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Introduction3-1

Definition Architecture3-2

Why have Architecture3-3 3-10

Definition Architecture3-5

The Vand Xstandards3-6

Advs and disadvs of standards3-7

Communication Architecture3-8

ISO Reference Model3-9

Standards making org3-4 Internet Architecture3-11

Manufactures Architecture3-12

A caveat about3-13

Layered architecture3-14

TCPIP Architecture

Network Management and Operation wwwgxmueducn

OBJECTIVESExplain the difference between architectures and standardsExplain the need for network architecture and standardsIdentify a number of communications standards-making orgDescribe the OSI model architectureDescribe TCPIP architectureDescribe the architecture of the InternetDiscuss the ADV and DISADV of layered architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

31 IntroductionDefinitions of architectures and standardsThe difference among themThe need of themSpecific example of themExamine adv amp disadv

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

32 DEFINITION OF ARCHITECTURES AND STANDARDS

Architecture is a plan or direction that is oriented toward the needs of the userNetwork architecture is a set of principles used as the basic for the design and implementation of a communications network

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

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310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

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312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

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IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

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OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 4: Computer Networking

Network Management and Operation wwwgxmueducn

OBJECTIVESExplain the difference between architectures and standardsExplain the need for network architecture and standardsIdentify a number of communications standards-making orgDescribe the OSI model architectureDescribe TCPIP architectureDescribe the architecture of the InternetDiscuss the ADV and DISADV of layered architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

31 IntroductionDefinitions of architectures and standardsThe difference among themThe need of themSpecific example of themExamine adv amp disadv

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

32 DEFINITION OF ARCHITECTURES AND STANDARDS

Architecture is a plan or direction that is oriented toward the needs of the userNetwork architecture is a set of principles used as the basic for the design and implementation of a communications network

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 5: Computer Networking

Network Management and Operation wwwgxmueducn

31 IntroductionDefinitions of architectures and standardsThe difference among themThe need of themSpecific example of themExamine adv amp disadv

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

32 DEFINITION OF ARCHITECTURES AND STANDARDS

Architecture is a plan or direction that is oriented toward the needs of the userNetwork architecture is a set of principles used as the basic for the design and implementation of a communications network

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 6: Computer Networking

Network Management and Operation wwwgxmueducn

32 DEFINITION OF ARCHITECTURES AND STANDARDS

Architecture is a plan or direction that is oriented toward the needs of the userNetwork architecture is a set of principles used as the basic for the design and implementation of a communications network

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 7: Computer Networking

Network Management and Operation wwwgxmueducn

It includes the organization of functions that must be performed by the network and the description of data formats and procedures

Network architecture=layer + protocols

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 8: Computer Networking

Network Management and Operation wwwgxmueducn

Network architecture features

May or may not conform to standards Donrsquot provides enough detail how network to be implemented Provides a set of generic concepts Most architecture (plan) are designed for the long term use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 9: Computer Networking

Network Management and Operation wwwgxmueducn

Single Layer Model First Communication Between Computer DevicesThe communication and application software be intermingled (To mix)

DEVICE A

Hardwareamp

Software

Hardwareamp

Software

DEVICE B1

The early networks were not flexibleSingle specification for all aspects of communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 10: Computer Networking

Network Management and Operation wwwgxmueducn

IBM SNA(System Network Architecture)

IBM 1974 by the first computer network architectureIBMrsquos SNA is a proprietary architectureNOTENot SNA(storage area network) Most network architectures developed since use a layered approach

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 11: Computer Networking

Network Management and Operation wwwgxmueducn

Communication standardThe rules that are established to ensure compatibility among similar communications products and servicesCommunications standards are the flesh on the architectural skeletonThey specify how a particular communications product serviceor interface will operate

V90 modem

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 12: Computer Networking

Network Management and Operation wwwgxmueducn

33 why have network architectures

1Communication system were becoming too complex2 wanted to be isolated from the complexities of the network3Wanted to connect different types of devices to the network4Distributed processing and client-server processing became practical5Network needed to be managed

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 13: Computer Networking

Network Management and Operation wwwgxmueducn

BackgroundCommunications vendors realized early standardscomputer manufacturers were slower to recognize the need for standardsCustomers demanded that product was standardization

34 TWO VIEWPOINTS ABOUT STANDARDS

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 14: Computer Networking

Network Management and Operation wwwgxmueducn

People who have a strong networking background see the computer as a tool to enhance a network`s capability

One

Tend to wait for standards and follow them closely

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 15: Computer Networking

Network Management and Operation wwwgxmueducn

Figure 3-1 Two different views of the relative roles of networks and computers

Those who have a strong computer background tend to focus on what can be done with software or specially designed circuit chips for computers

They forge ahead of the standards-making process

Two

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 16: Computer Networking

Network Management and Operation wwwgxmueducn

Purport While neither viewpoint is wrong it leads to differing philosophiesBoth are legitimate and have their place

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 17: Computer Networking

Network Management and Operation wwwgxmueducn

35 STANDS AND STANDS-MAKING ORGANIZATIONS Because of the recognized need for common international standards there is a great deal of cooperation among communications standards making organizations Data communication standards are more complicated than Voice communication standardsEarly standards were mostly electrical in nature The standards-setting process is slowWriting standards is difficult work

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 18: Computer Networking

Network Management and Operation wwwgxmueducn

ITU (The International Telecommunication Union)

1865 in the U S was established in Paris 1947 as part of the United Nations members from 188 countries headquartered in Geneva SwitzerlandThe most important telecommunications standards-setting organization in the world is the ITU ITU-T has created two sets of standards for the electrical connection of terminals to communications networks

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 19: Computer Networking

Network Management and Operation wwwgxmueducn

ISOInternational Standards OrganizationDonrsquot confuse the OSI with ISO and IOSISO means the international organization for standardizationIOS (internet operation system) is used in CISCO systemrsquos routers and switches

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 20: Computer Networking

Network Management and Operation wwwgxmueducn

Figure of the organizations involved in setting telecommunications standards or in passing input to the standards-setting bodies

The American National Standards Institute (ANSI) is not involved in setting communications standards The official TCPIP model is now maintained by the IETFAll communications standards are developed by one organization the ISOF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 21: Computer Networking

Network Management and Operation wwwgxmueducn

36 V STANDARD XSTANDARD

The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called the V and X standards

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 22: Computer Networking

Network Management and Operation wwwgxmueducn

Vstandards define the connection of digital equipment to the PSTN`s analog linesV32 V33 V42 standard for the use of telephone transmission of data made a clear statement XstandardsDefine the connection of digital equipment to digital linesEG X25 X400 X500

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 23: Computer Networking

Network Management and Operation wwwgxmueducn

37 ADVANTAGES AND DISADVANTAGES OF STANDARDS

Adv Standards allow products from multiple vendors to be connected to one another and to communicate

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 24: Computer Networking

Network Management and Operation wwwgxmueducn

disadvanceThe standards-setting process is slowStandards tend to freeze technologyMultiple conflicting standardsThe standards-setting process can occur quickly(Writing standards is relatively easy ) when an architecture is in placeF

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 25: Computer Networking

Network Management and Operation wwwgxmueducn

38 COMMUNICATIONS ARCHITECTURESISO and ITU-T developed OSI reference model in 1978OSI-RM Open Systems Interconnection reference modelThe standards development process took so long that the osi model never came into widespread useIt is the standard reference point by which data communications networks are described

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 26: Computer Networking

Network Management and Operation wwwgxmueducn

39 THE ISO`S OSI REFERENCE MODEL391 Objective Provide a basis for interconnecting dissimilar systems for the purpose of information exchange Define communications rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 27: Computer Networking

Network Management and Operation wwwgxmueducn

OSI and most network architecture use a layered approach A layer in the OSI RM represents a component of the total process of communicating Each one layer requests services from the layer below it N layer Provide services to N+1 layer The same network any two-system must have the same level The actual physical communication completed only in the bottom layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 28: Computer Networking

Network Management and Operation wwwgxmueducn

1) Layering forces the modularization of function Dealing with complex systemsThe output of laying definition process is standardseases maintenance updating of systemOne layer can be changed without affecting other layersDifferent implementations can be substituted relativelyTransparently

Why layering

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 29: Computer Networking

Network Management and Operation wwwgxmueducn

Layer Layer requires reasonably sophisticated software and hardware at each end of the connection

前置处理机CCP

中央主机 中央主机中央主机

前置处理机

前置处理机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 30: Computer Networking

Network Management and Operation wwwgxmueducn

The philosopher-translator-Secretary architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 31: Computer Networking

Network Management and Operation wwwgxmueducn

CN scientists

CN Translate

CNTelegrafisten

Telex machine

JP scientists

JP Translate

JPTelegrafisten

Telex machine

protocol

protocol

protocol

protocol

Scientific opinion

English

Letters

Telegraph code

Example Scientific exchange layered

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 32: Computer Networking

Network Management and Operation wwwgxmueducn

Network Architecture Layered principle Basic concept

Entity Can send or receive any information of hardware software process Peer layer Two different systems the same level Interface Interaction between the two neighboring layerSERVE for the upper classes a capacity to provide services through the interface Protocol Communication both in communication must comply with the rules

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 33: Computer Networking

Network Management and Operation wwwgxmueducn

SYSA

SYSBentity Pee

r layerpeer

entity

server

Physical communication line

Layered network Architecture SYS

B

P3P2P1

2 1

3 2 1

Physical communication line

3

N+1 N N-1

N+1 N N-1Pn-1

Pn

Pn+1

SYSA

interfact

The way that the interaction between the layers actually takes place is that each one requests services from the layer above it

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 34: Computer Networking

Network Management and Operation wwwgxmueducn

Services The way that the interaction between the layers actually takes place is that each one requests services from the layer above itEach layer provides services to the next higher layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 35: Computer Networking

Network Management and Operation wwwgxmueducn

Service PrimitivesPrimitiv

eMeaning

Request An Entity wants the service to do some work

Indication

An Entity is to be informed about an event

Response

An Entity wants to respond to an event

Confirm The Response to an eariler request has come back

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 36: Computer Networking

Network Management and Operation wwwgxmueducn

服务用户( N+1 )

服务提供者( N )系统 A 服务用户

( N+1 )服务提供者

( N )系统 B

无需证实Request

Indication

RequestIndication

Response

Confirm

需证实PDU

Relations among Service Primitives

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 37: Computer Networking

Network Management and Operation wwwgxmueducn

电话系统工作示例例如张三打电话请李四吃饭服务提供者为电话局 ① CONNECT request 张三拨李四的电话号码 ② CONNECT i ndi cati on 李四的电话振铃 ③ CONNECT response 李四摘机 ④ CONNECT confi rm 张三听到振铃停止知道有人应答 ⑤ DATA request 张三说话发出邀请 ⑥ DATA i ndi cati on 李四听到张三的邀请 ⑦ DATA request 李四说话接受邀请 ⑧ DATA i ndi cati on 张三听到李四的答复 ⑨ DI SCONNECT request 李四挂机 ⑩ DI SCONNECT i ndi cat i on 张三听到李四挂机也挂机

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 38: Computer Networking

Network Management and Operation wwwgxmueducn

Protocols can provide a service for upper layer

Protocols is ldquolevelrdquo But Services is ldquoVertical rdquo Service is adopted by the lower layer of

interface Functions is the internal activities

Services interface protocols and functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 39: Computer Networking

Network Management and Operation wwwgxmueducn

Services to Protocols Relationship

The relationship between a service and a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 40: Computer Networking

Network Management and Operation wwwgxmueducn

Layers of the ISOrsquos OSI reference model The layers of the OSI model on each node

communicate with each other

A layer in the OSI model represents a compon-ent of the total process of communicating T

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 41: Computer Networking

Network Management and Operation wwwgxmueducn

Actual communication passes down through the layers on the sending node and then up through the layers on the receiving node

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 42: Computer Networking

Network Management and Operation wwwgxmueducn

X25The first three layers of the OSI model have been standardized and together are called the X25 standard for data transmission

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 43: Computer Networking

Network Management and Operation wwwgxmueducn

GOSIP government open system Interconnetion Protocola subset of the OSI model that vendors must support if they want to sell network services or equipment to the US governmentGOSIP is neither a new architecture nor a New standardIt is a more precise specification of what parts of the OSI model the government will use

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 44: Computer Networking

Network Management and Operation wwwgxmueducn

392The Function Of Each Layer LAYER 1 THE PHYSICAL LINK LAYER

It specifies the electrical characteristics between the communications line and the terminal or computer CablingInterconnect methods (topology devices)Data encoding (bits to waves)Electrical properties

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 45: Computer Networking

Network Management and Operation wwwgxmueducn

Typical equipment

What are the Physical Layer components on my computer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 46: Computer Networking

Network Management and Operation wwwgxmueducn

Physical Layer

This is the only layer at which actual bits passThe only layer that is implemented strictly in hardwareThe only layer that actually communicates across the transmission line to the other nodeLayer1 only knows about a strem of bitsData transmission unit is bits Transmission media does not belong to the physical layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 47: Computer Networking

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 48: Computer Networking

Network Management and Operation wwwgxmueducn

LAYER2 THE DATA LINK LAYER

FunctionFraming (成帧)Line disciplineFlow controlError control

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 49: Computer Networking

Network Management and Operation wwwgxmueducn

Data link layer It is responsible for establishing a link between two points on a network and ensuring that data are successfully transferred between the two points Divide the data into smaller units for transmission( FRAME )Detecting transmission errors and correcting errors

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 50: Computer Networking

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 51: Computer Networking

Network Management and Operation wwwgxmueducn

Network Interface Card Bridge

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 52: Computer Networking

Network Management and Operation wwwgxmueducn

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 53: Computer Networking

Network Management and Operation wwwgxmueducn

LAYER 3 THE NETWORK LAYER

It is responsible for routing a message all the way through the network from the transmitter to the receiver is the network layer

Transmission units is package

Point-to-point

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 54: Computer Networking

Network Management and Operation wwwgxmueducn

LAYER4 THE TRANSPORT LAYERIdentifies actual address but donrsquot know routeDetermine if the entire message was received correctlyis responsible for end-to-end (source to destination) packet delivery Taskhellip hellip两端点间可靠的透明数据传输(应用进程间的逻辑通信)

networkend-to-end

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 55: Computer Networking

Network Management and Operation wwwgxmueducn

Also calculates a check sum for the entire messagewhich is recalculated by layer4 at The receiving end and compared

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 56: Computer Networking

Network Management and Operation wwwgxmueducn

LAYER 5 THE SEEION LAYER

It is responsible for establishing the communications rules between specific machines or applications provides the mechanism for opening closing and managing a session between end-user application processes

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 57: Computer Networking

Network Management and Operation wwwgxmueducn

Session Layer Dialog

Pacing the rate of transmission so data are not sent faster than the receiver can handle it

Certain accounting function

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 58: Computer Networking

Network Management and Operation wwwgxmueducn

LAYER 6 THE PRESENTATION LAYER

Provides common data formatting between communicating devicesComponents make sure the receiving station can read the transferred data

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 59: Computer Networking

Network Management and Operation wwwgxmueducn

Direct and Indirect Methods of Translation Concept of Encryption and Decryption

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 60: Computer Networking

Network Management and Operation wwwgxmueducn

Data Compression Methods Run-Length Encoding

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 61: Computer Networking

Network Management and Operation wwwgxmueducn

LAYER 7 THE APPLICATION LAYER It is ldquowhererdquo the user works at a terminal with computer softwareIt provides a set of interfaces for applications to obtain access to networked services as well as access to the kinds of network services that support applications directlyOSI - FTAMVTMHSDSCMIP

TCPIP - FTPSMTPTELNETDNSSNMPAlthough the notion of an application process is common to both their approaches to constructing application entities is different

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 62: Computer Networking

Network Management and Operation wwwgxmueducn

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理) NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Five common application of OSI

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 63: Computer Networking

Network Management and Operation wwwgxmueducn

Typical equipmentGateway proxy firewall

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 64: Computer Networking

Network Management and Operation wwwgxmueducn

Summary of Layer Functions

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 65: Computer Networking

Network Management and Operation wwwgxmueducn

OSI 模型是协助网络检修人员识别网络问题一种理想的框架    

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 66: Computer Networking

Network Management and Operation wwwgxmueducn

310 TCPIP ARCHITECTURETCPIP Transmission Control ProtocolInternet Protocol

The official TCPIP model is now maintained by the IETF(ITU-T) Because progress on setting standards for the OSI model was slow DARPA developed a set of protocols called TCPIPTCPIP has become the de facto standard protocol for internets

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 67: Computer Networking

Network Management and Operation wwwgxmueducn

The acronym of the US governments version of the open system interconnection protocol is InternetIn 1969ARPA funded and created the ldquoARPAnetrdquo network

In 1975Convert from experimental to operational networkTCPIP begun to be developed

In 1983The TCPIP is adopted as Military StandardsARPnet MILNET + ARPnet = Internet

In 1985The NSF created the NSFnet to connect to InternetNSF = National Science Foundation

In 1990ARPA passed out of existence and in 1995 the NSFnet became the primary Internet backbone network

TCPIP and the Internet

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 68: Computer Networking

Network Management and Operation wwwgxmueducn

TCPIP 4-layer or 5-layer

ApplicationLayer

TransportLayer

InternetLayer

Network Interface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

Physical

CISCO and IBM use the four-layer modelWe use the five-layer model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 69: Computer Networking

Network Management and Operation wwwgxmueducn

A comparison of the layers of the OSI reference model and the implementation of TCPIP

Network Interface

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 70: Computer Networking

Network Management and Operation wwwgxmueducn

PROTOCOLSEach layer has several protocolsA layer define a data communication function that may be performed by certain protocolsA protocol provides a service suitable to the function of that layer

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 71: Computer Networking

Network Management and Operation wwwgxmueducn

TCPIP and the OSI Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 72: Computer Networking

Network Management and Operation wwwgxmueducn

Application layerProvide services that can be used by other applicationsIncorporate the functions of top 3 OSI layersContains the programming required to support the user`s applicationDifferent module are required for each application

OSI application TCPIP application

CMIP (通用管理信息协议) SNMP NETVIEW

DS (目录服务) NDS NTDS

FTAM (文件的传输存取和管理)

NETWARE NFS

MHS (报文处理系统)VTP (虚拟终端协议) TELNET

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 73: Computer Networking

Network Management and Operation wwwgxmueducn

Transport layerApplication layer directly run over the transport layer corresponding to OSI transport layerTwo kinds of services TCP amp UDP

TCPmdashTransmission Control Protocol reliable connect-oriented transfer of a byte stream

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 74: Computer Networking

Network Management and Operation wwwgxmueducn

UDPmdash(User Datagram Protocol)best-effort connectionless transfer of

individual messagesThe advantage of a connectionless protocol is that there is no setup time at the beginning of the communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 75: Computer Networking

Network Management and Operation wwwgxmueducnFigure 211

Internet layer

1 Transfer of information across networks through gatewaysrouters2 Global unique IP address and IP packets

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network Interface

Network 1 Network 2

RouterGateway

The internet layer of TCPIP routes data between networks when necessary using the IP protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 76: Computer Networking

Network Management and Operation wwwgxmueducnFigure 211

Network interface layer

1 Corresponding to part of OSI network layer and data link layer2 Different network interfaces X25 ATM frame relay Ethernet etc

IP packet

Machine A Machine B

ApplicationTransport

InternetNetwork Interface

ApplicationTransportInternet

Network InterfaceInternet

Network InterfaceS

Network 1 Network 2

RouterGateway

Packetof network1

Packetof network1

IP packet

IP packet

Packetof network2

IP packet

Packetof network2

Handles the connection between the end system and the network to which it is attached

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 77: Computer Networking

Network Management and Operation wwwgxmueducn

Some Protocols in TCPIP Suite

Internet

Transport

App

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 78: Computer Networking

Network Management and Operation wwwgxmueducn

A Critique of the TCPIP Reference ModelProblemsService interface and protocol not distinguishedNot a general modeldoes not require strict layering

Applicationayer

TransportLayer

InternetLayer

NetworkInterface

ApplicationLayer

TransportLayer

InternetLayer

NetworkInterface

(a) (b)

TCPIP network architecture

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 79: Computer Networking

Network Management and Operation wwwgxmueducn

311 Architecture of the Internet

The Internet is a network of networks Guide Informal architectural it was not formalized until later

The architects of the Internet dont insist on documenting every detail of Internet operation before implementation work began

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 80: Computer Networking

Network Management and Operation wwwgxmueducn

The four initial requirements confronting the Internetrsquos architects were Multiplexing Survivability service generalitysupporting diverse network technologies The primary initial requirement that the architects of the Internet addressed were diverse network technologies

Design Guidelines

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 81: Computer Networking

Network Management and Operation wwwgxmueducn

Designer

security

What entities Naming addressing routing

ModularizedResources are allocated

Concerned with

It wasn`t until 1991 that the Word Wide Web was introducee and Internet began to move from being an academic and military tool to being the tool it now os for researchsalesand communication

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 82: Computer Networking

Network Management and Operation wwwgxmueducn

312 MANUFACTURERS`ARCHITECTURES Before OSI RM IBM SNA DEC DNA Burroughs BNSIt is a proprietary architectureManufacturers that developed network architectures were primarily interested in developing proprietary architectures on which to base their future products

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 83: Computer Networking

Network Management and Operation wwwgxmueducn

IBM SNA

Because of customer and market pressuresthe situation changed and computer manufacturers became fully supportive of the international communications standards

DEC DNAIBM SNA

SNA DNA ARCHITECTURES

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 84: Computer Networking

Network Management and Operation wwwgxmueducn

OTHER ARCHITECTUREThe ATM Reference ModelNovell NetWare RMWindows NT RMA Proposed Reference Model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 85: Computer Networking

Network Management and Operation wwwgxmueducn

The ATM reference model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 86: Computer Networking

Network Management and Operation wwwgxmueducn

NOVELL NETWARE RM

各种应用服务

应用层

表示层

会话层

传输层

网络层

数据链路层

物理层

SPX

IPX

网络接口卡与 网卡驱动程序

OSI Novell NetWare

IPXSPX ( internetwork packet exchange sequences packet exchange)

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 87: Computer Networking

Network Management and Operation wwwgxmueducn

Windows NT 网络体系与模型

传输协议

客户机层

7

6

1

2

3

45

应用层

表示层

传输层

会话层

数据链路层

物理层

网络层

OSI模型

以太网令牌环或其他

环境子系统

IO文件 命名管道邮mailslots件槽

NDIS30接口NDIS环境和驱动

NetBEUI TCPIP

重定向器

TDI服务器

服务器

协议NDIS

协议

SMB

Windows NT RM

NetBEUI NWLink

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 88: Computer Networking

Network Management and Operation wwwgxmueducn

A Proposed Reference Model

应 用 层

传 输 层

网 络 层

数据链路层

物 理 层

Andrew STanenbaum5 layers of RM No presentation layer session

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 89: Computer Networking

Network Management and Operation wwwgxmueducn

3-13 A CAVEATIt is important to understand that writing the specifications for communications architectures and the related standards is difficult workAs actual communications systems have been implemented over the years most have not strictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 90: Computer Networking

Network Management and Operation wwwgxmueducn

3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES

1Layering forces the modularization of function2 Good flexibility 3 Easy to achieve and maintain 4 Scalability 5Standardization A protocol stack is software that implements the layers of a protocol

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 91: Computer Networking

Network Management and Operation wwwgxmueducn

OSI vs TCPIP Reference Models

OSI introduced concept of services interface protocols These were force-fitted to TCP later In OSI reference model was done before protocols In TCP protocols were done before the model OSI Standardize first build later TCP Build first standardize later As actual communications systems have been implemented over the years most have notstrictly followed the OSI model

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 92: Computer Networking

Network Management and Operation

课后习题

A X25 standard for data transmission

1 The first three layers of the OSI model have been standardized and together are called the (   ) A

B V standard

D Consolidated Transmission Protocol

C consolidated transmission standard

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 93: Computer Networking

Network Management and Operation

课后习题

D the V and X standards

2 The ITU-T has created two sets of standards for the electrical connection of terminals to communications networks They are called (   ) D

A the ISO and OSI standards

B the TCP and IP standardsC the PC and modem standards

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 94: Computer Networking

Network Management and Operation

课后习题

C is a proprietary architecture

3 IBMrsquos SNA (   ) C

A was never widely implemented

B is a data link protocol

D was an advanced mainframe computer for its time

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 95: Computer Networking

Network Management and Operation

课后习题

C a set of principles used as the basis for the design and implementation of a communications network

4 A network architecture is (   ) C

A the plan for the Internetrsquos evolution

B a description of how a network is to be implemented

D None of the above

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 96: Computer Networking

Network Management and Operation

课后习题

D All of the above

5 The Interne (   ) D

A is implemented using the TCPIP protocol

B has the attribute of service generality

C allows for diverse network technologies

AnswerRedo Next

times

times

times

radic

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 97: Computer Networking

Network Management and Operation

课后习题1 A set of principles used as the basis for the design and

implementation of a communications network is called a ________________network architecture

Answer

Exercises

2The_____________ reference model is the standard reference point by which data communications networks are described and measured

OSI

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 98: Computer Networking

Network Management and Operation

课后习题3Two telephone callers may be connected but they will not be able to ___________ and exchange information if they speak different languages

communicate

Answer

Exercises

4The________ _________ layer specifies the electrical characteristics between the communications line and the terminal or computer system

Physical link

Answer

Chapter 3 Network Architetures and Standarts

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 99: Computer Networking

Network Management and Operation

课后习题5When data are received the OSI presentation layer is responsible for ___________the data to meet the needs of the application layer

formatting

Answer

Exercises

Chapter 3 Network Architetures and Standarts

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100
Page 100: Computer Networking

Network Management and Operation wwwgxmueducn

  • Slide 1
  • Slide 2
  • Chapter 3 Network Architetures and Standarts
  • OBJECTIVES
  • 31 Introduction
  • 32 DEFINITION OF ARCHITECTURES AND STANDARDS
  • Chapter 3 Network Architetures and Standarts (2)
  • Network architecture features
  • Single Layer Model
  • IBM SNA(System Network Architecture)
  • Communication standard
  • 33 why have network architectures
  • 34 TWO VIEWPOINTS ABOUT STANDARDS
  • One
  • Figure 3-1 Two different views of the relative roles of ne
  • Purport
  • 35 STANDS AND STANDS-MAKING ORGANIZATIONS
  • ITU (The International Telecommunication Union)
  • ISOInternational Standards Organization
  • Figure of the organizations involved in setting telecommunicati
  • 36VSTANDARD XSTANDARD
  • Chapter 3 Network Architetures and Standarts (3)
  • 37 ADVANTAGES AND DISADVANTAGES OF STANDARDS
  • disadvance
  • 38 COMMUNICATIONS ARCHITECTURES
  • 39 THE ISO`S OSI REFERENCE MODEL
  • Chapter 3 Network Architetures and Standarts (4)
  • Why layering
  • Layer
  • Slide 30
  • Chapter 3 Network Architetures and Standarts (5)
  • Network Architecture Layered principle
  • Layered network Architecture
  • Services
  • Service Primitives
  • Relations among Service Primitives
  • Slide 37
  • Chapter 3 Network Architetures and Standarts (6)
  • Services to Protocols Relationship
  • Layers of the ISOrsquos OSI reference model
  • Actual communication passes down through the layers on the send
  • X25
  • GOSIP
  • 392The Function Of Each Layer
  • Typical equipment
  • Slide 46
  • Slide 47
  • LAYER2 THE DATA LINK LAYER
  • Data link layer
  • Chapter 3 Network Architetures and Standarts (7)
  • Chapter 3 Network Architetures and Standarts (8)
  • Slide 52
  • LAYER 3 THE NETWORK LAYER
  • LAYER4 THE TRANSPORT LAYER
  • Chapter 3 Network Architetures and Standarts
  • LAYER 5 THE SEEION LAYER
  • Slide 57
  • LAYER 6 THE PRESENTATION LAYER
  • Slide 59
  • Slide 60
  • LAYER 7 THE APPLICATION LAYER
  • Five common application of OSI
  • Typical equipment (2)
  • Slide 64
  • OSI模型是协助网络检修人员识别网络问题一种理想的框架
  • 310 TCPIP ARCHITECTURE
  • TCPIP and the Internet
  • TCPIP 4-layer or 5-layer
  • A comparison of the layers of the OSI reference model and the i
  • PROTOCOLS
  • Slide 71
  • Application layer
  • Transport layer
  • UDPmdash(User Datagram Protocol)
  • Chapter 3 Network Architetures and Standarts (9)
  • Chapter 3 Network Architetures and Standarts (10)
  • Some Protocols in TCPIP Suite
  • A Critique of the TCPIP Reference Model
  • 311 Architecture of the Internet
  • Chapter 3 Network Architetures and Standarts (11)
  • Designer
  • 312 MANUFACTURERS`ARCHITECTURES
  • IBM SNA
  • OTHER ARCHITECTURE
  • Slide 85
  • NOVELL NETWARE RM
  • A Proposed Reference Model
  • 3-13 A CAVEAT
  • 3-14 ADVS AND DISADVS OF LAYERED ARCHITECTURES
  • OSI vs TCPIP Reference Models
  • 课后习题
  • 课后习题 (2)
  • 课后习题 (3)
  • 课后习题 (4)
  • 课后习题 (5)
  • 课后习题 (6)
  • 课后习题 (7)
  • 课后习题 (8)
  • Slide 100