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Lectures/LAN-Lec01-Introduction.ppt

1

..

2007

. ..

-

"" (, , )

("" )

( )

( ) (CD/DVD-ROM, flash- ..)

,

file.txt

,

, ,

(+)

(-) ,

(-)

MSOffice

MSOffice

MSOffice

MSOffice

-

-

,

,

, (, )

,

, -

-

, ,

,

-

-

C:

D:

E:

C:

D:

-

-

,

-

; ,

..

,

,

Windows , (Remote Registry, MMC,)

Web- (swat)

,

(, Windows XP/Vista)

(Remote Desktop, PC Anywhere, RAdmin ..)

,

telnet/ssh (UNIX)

X Window , (), ,

Windows NT 4.0 Terminal Server Windows

,

(, )

..

, ,

, ,

, ,

,

(1)

, (, )

(, MPI)

(2)

,

,

(2)

,

,

Message Passing Interface (MPI, ) ,

MPI , ,

MPI

MPI,

- (ICQ, MSN-messenger,)

(Skype,)

..

- .

.. , .. . . , , . : , 2001.

TCP/IP. Microsoft Windows 2000 Server. .: , 2001.

Lectures/LAN-Lec02-Architecture.ppt

2

..

2007

. ..

Windows

/;

;

;

;

,

?

(, )

DOS

ipx.com

ipx.com

(, net.exe)

DOS

ipx.com

:

?

?

DOS?

N

1

( )

N-1

2

( )

DOS (2)

lsl.com

3c509.com -

ipxodi.com -

(, net.exe)

lsl.com

ipxodi.com

3c509.com

DOS (2)

lsl.com ipxodi.com

, (),

?

lsl.com, ipxodi.com

3c509.com

Windows

Windows

( NT/2000/XP/)

TDI

NDIS

Windows

(Network Interface Card, NIC) ,

NIC

(IRQ number)

- (I/O Base)

Windows

Network Driver Interface Specification (NDIS) ,

NDIS

NIC

Windows

Transport Driver Interface (TDI) .

TCP/IP

NWLink ( IPX/SPX, Microsoft Windows)

NetBEUI (NetBIOS Extended User Interface)

(DLC, IrDA,)

Windows

API

Winsock API

NetBIOS API

Telephony API

Messaging API

WNet API

Windows

(InterProcess Communication, IPC)

DCOM (Distributed Component Object Model)

RPC (Remote Procedure Call)

Pipes

MailSlots

Windows

Windows

""

" "

Windows

( NT/2000/XP/)

TDI

NDIS

DCOM

RPC

Pipes

MailSlots

Winsock

TAPI

NetBIOS API

TCP/IP

NetBEUI

NWLink

Windows

(binding)

(, ), ,

a 1

NIC1

TDI

TCP/IP

NetBEUI

a 2

NIC2

NDIS

N

1

N-1

2

, ;

, ;

, ;

, ;

,

. , , ,

,

,

, , (header) / (trailer),

,

N

1

N-1

2

, ,

,

N

1

N-1

2

/

, , i- , i- , ()

/

N

1

N-1

2

N

1

N-1

2

/

N- N

, ,

, ,

(Open Systems Interconnection Reference Model), 1


.. , .. . . , , . : , 2001.

Lectures/LAN-Lec03-OSIRM-1.ppt

3

ISO/OSI (.1)

..

2007

. ..

(Open Systems Interconnection Reference Model)

ISO/OSI

(IBM, Honeywell, Digital .) , , ,

1978 . (International Standards Organization, ISO) , Open Systems Interconnection (OSI) Reference Model

ISO/OSI

,

, ,

ISO/OSI

OSI , - -

,

,

,

, , ,

ISO/OSI

(Application)

(Data Link)

(Presentation)

(Session)

(Transport)

(Network)

(Physical)

ISO/OSI Reference Model

OSI ( )

( )

(TCP/IP)

ISO/OSI

, , ,

( , , , )

( )

( )

t

U

1

1

1

1

1

0

0

0

/

(transmitter-receiver) , ,

10Base5, 10Base2, 10BaseT Ethernet

ISO/OSI

(frame)

, , ,

MAC- (MAC Media Access Control)

A

B

MAC- MAC-

A

B

MACA

MACB

MACA

MACB

,

A

B

MACA

MACB

CRC (Cyclical Redundancy Check)

CRC ,

CRC , , (, Ethernet 2-32)

A

B

MACA

MACB

,

, ( ) . .

, , . .

, ,

( ), , ,

Ethernet

Token Ring

FDDI

ISO/OSI



.. , .. . . , , . : , 2001.


4

ISO/OSI (.2)

..

2007

. ..


ISO/OSI

, , ,

A B?

A

B

C D

,

A

B

C

D

- ,

,

(hop)

,

,

1

A

B

2

3

C

D

1

2

1

1

2

2

A: 1.1

C: 1.2 2.1

D: 2.2 3.1

B: 3.2

1

A

B

2

3

C

D

1

2

1

1

2

2

,

,

,

, (" ")

()

" ", ,

, , ,

, , , ,

() ;

( )

,

A

1

A

B

2

3

C

D

1

2

1

1

2

2

..

11.11

21.22

21.23

( )

, ( )

A (1.1) 1.2 , MAC- 1.2

1

A

C

1

2

MACA

MACB

, , (MTU Maximum Transmission Unit)

, , ,

Ethernet

MTU = 1500

A

C

, ,

IP TCP/IP

IPX Novell

ISO/OSI

( ) ,

(, , )

A

B

A1

A2

A3

B1

B2

B3

, " + "

, TCP/IP IP-:N

A

B

A1

A2

A3

B1

B2

B3

2

, ,

,

1

2

,

,

,

( )

1

2

, , " ", ""

A

B

A1

A2

A3

B1

B2

B3

( )


IEEE 802


.. , .. . . , , . : , 2001.


5

ISO/OSI (.3)

..

2007

. ..


IEEE 802

ISO/OSI

, ,

, NetBIOS- 16- , NetBIOS- , , , 15 ,

A

B

A

_

_

_

_

0

A

_

_

_

_

_

B

_

_

_

_

0

B

_

_

_

_

_

,

A

B

A

_

_

_

_

0

A

_

_

_

_

_

B

_

_

_

_

0

B

_

_

_

_

_

A.A

MACA

B.B

MACB

, ,

A

B

A

_

_

_

_

0

A

_

_

_

_

_

B

_

_

_

_

0

B

_

_

_

_

_

,

, , ,

A

B

A

_

_

_

_

0

A

_

_

_

_

_

B

_

_

_

_

0

B

_

_

_

_

_

,

,

, , ,

ISO/OSI

,

, .

A

B

: x86

: Windows

: POWER

: Linux

char name[4] = "";

short num = 4096;

char name[4] = "";

short num = 16;

,

A

B

: x86

: Windows

: POWER

: Linux

char name[4] = "";

short num = 4096;

char name[4] = "";

short num = 4096;

ASCII EBCDIC

cp866, CP-1251, ISO-8859-5,

KOI8-R ..

CR CR/LF

SSL (Secure Socket Layer), TCP/IP

ISO/OSI

IEEE 802

IEEE 802

IEEE 802 .

IEEE Institute of Electrical and Electronics Engineers

802 1980

IEEE 802

802

(ISO) ISO 8802

(ANSI)

..

IEEE 802

IEEE 802 OSI

(Logical Link Control, LLC)

(Media Access Control, MAC)

IEEE 802

802.1 802,

802.2 (LLC)

802.3 (Carrier Sense Multiple Access with Collision Detection, CSMA/CD)

802.4 (Token Bus)

802.5 (Token Ring)

802.6 (Metropolitan Area Network, MAN)

IEEE 802

802.7

802.8

802.9

802.10

802.11

802.12 (Demand Priority Access LAN, 100BaseVG-AnyLan)

IEEE 802

IEEE 802


.. , .. . . , , . : , 2001.

Lectures/LAN-Lec06-Topologies.ppt

6

..

2007

. ..

(, , )

, ,

,

(bus)

(star)

(ring)

""

, . , , MAC-

?

, ,

, . , . , .

, . .

""

NIC

,

""

( ),

, 80-

"" (hub),

. , "" , .

, "" ,

/

.

""

NIC

( )

, "" , ""

""

UpLink-

""

, ,

, ( " ")

"" ,

/?

,

. , "",

()

()

()

NIC

, ""

()

NIC

( ())

, , "" ()

, Token Ring,

()

, ,

()

"" ( )

()

"" ()

( , , )

, , ,

()

"" ()

, ,

.. , .. . . , , . : , 2001.

Lectures/LAN-Lec07-Cables.ppt

7

..

2007

. ..

( -)

( )

, ( )

. ( ),

""

,

. ,

, ,

( ) ( )

. :

().

( , )

Ethernet ( 10Base-5)

EIA/TIA-568 ( RG-8 RG-11)

EIA/TIA-568A

1/12" 2,17

1/2" 12

50

10Base-5

500

50

"5-4-3"

5

4 ,

3 ( )

2500

10Base-5

, (vampire tap, " ")

NIC AUI (Attachment Unit Interface), 4

DB-15

AUI 50

100

2,5

10Base-5

AUI

-

Ethernet ( 10Base-2)

EIA/TIA-568

RG-58 /U

RG-58 A/U

RG-58 C/U RG-58 A/U

EIA/TIA-568A

1/30" 0,85

5

50

10Base-2

185

50

"5-4-3"

5

4 ,

3 ( )

925

10Base-2

NIC BNC (British Naval Connector)

BNC-

BNC- BNC T-, , , BNC- NIC

30

0,5

10Base-2

BNC-, ,

BNC-

BNC T-

BNC

BNC -

10Base-2

( , 10Base-5)

10Base-5

, ,

. "" "".

- , . - ( 4), .

(Unshielded Twisted Pair, UTP)

(Shielded Twisted Pair, STP) ,

Screened Twisted Pair (ScTP)

Foiled Twisted Pair (FTP)

Pair in Metal Foil (PiMF) , -

..

(Ethernet, Token Ring, ATM ..)

EIA/TIA-568 EIA/TIA-568A UTP

IBM (Type1, Type2 ..) UTP STP

UTP

1

( 20 /c)

2

2 IBM

4 /

UTP

3 (1991 .)

" " (EIA-568) 3 16

10 /c

100

4 (1993 .)

20

3 ( 16 /)

100

UTP

5

5 100

100

6

6 200 ( 250)

7

7 600

8- RJ-45

EIA/TIA-568 /

2

EIA/TIA-T568A

-

-

-

-

EIA/TIA-T568B

-

-

-

-

EIA/TIA-568 2

(T568A T568B)

()

( T568A, T568B)

,

10Base-T

3

100

"4 ": 4

( ) 500

- ,

, ( , )

(, )

MIC, ST, SC

( )

5-10

/

50-60 ( : 50/125 62,5/125 )

500-800

,

1,55 , 1,3 , 0,85

( )

, , ( )

.

, , 25

10Base-F

(2 )

500-800 1

FOIRL (Fiber Optic Inter-Repeater Link)

1000

4-

2500 ( , )

10Base-FL

2000

4-

2500

10Base-FB

2000

5- (!)

2740

,

.. , .. . . , , . : , 2001.

Lectures/LAN-Lec08-Coding.ppt

8

,

..

2007

. ..

( )

, , , [1]

( )

( )

( )

. "" (.. )

() ( )

() ( )

()

ISO/IEC 11801

EN 50173

ANSI/TIA/EIA 568-

( )

, ,

( )

, - ,

,

5-10

( ) 25

Wi-Fi (Wireless Fidelity)

2-15 (Access Point, AP), 50 ,

25

2

( )

( )

5-10 / ( ) 100 /

( .)

(, )

,

-

t

t

,

t

t

,

t

t

, . ,

Not Return to Zero (NRZ)

Not Return to Zero with ones Inverted (NRZi)

Multi-Level Transition-3 (MLT-3)

Return to Zero (RZ)

2B1Q

NRZ

Not Return to Zero (NRZ)

, ( )

( )

RS232

t

0

1

0

1

1

0

0

0

NRZi

Not Return to Zero with ones Inverted (NRZi)

,

t

0

1

0

1

1

0

0

0

MLT-3

Multi-Level Transition-3 (MLT-3)

: +U, 0, -U, 0, +U, 0,

, NRZ

t

0

1

0

1

1

0

0

0

RZ

Return to Zero (RZ)

,

t

0

1

0

1

1

0

0

0

(-II)

,

2

Ethernet, Token Ring

t

0

1

0

1

1

0

0

0

2B1Q

2B1Q

4 2 , : 00 -U1, 01 -U2, 10 +U2, 11 +U1

t

0

1

0

1

1

0

0

0

, ,

,

4B/5B 4 5, ( FDDI Fast Ethernet)

8B/6T 8 6 3

, (Ai) (Bi-1,Bi-2,),

Bi = Ai ^ Bi-1 ^ Bi-2

,

-

( )

Ethernet

Token Ring

.. , .. . . , , .

: , 2001.

.., .. .

: ., 2005

Lectures/LAN-Lec09-LANTechnologies.ppt

9

..

2007

. ..

Ethernet

Token Ring

, ( / )

ALOHA

CSMA/CD

CSMA/C

CDMA

ALOHA

ALOHA

, . .

,

, , ,

CSMA/CD

Carrier Sensitive Multiple Access with Collision Detection (CSMA/CD)

,

, ( )

, ,

ALOHA ( ) , ALOHA , CSMA/CD

CSMA/CD

, CSMA/CD ,

, ,

, A , B ( ), B , , A

, , , , A,

A

B

CSMA/CD

CSMA/CD

, , ,

(% ),

CSMA/CD

CSMA/CA

Carrier Sensitive Multiple Access with Collision Avoidance (CSMA/CA)

, N

0 N-1

, N

, 1 ( )

, ,

CSMA/CA

t

1

0

0

1

0

1

2

3

1

1

1

0

0 3, 0,1 2

CSMA/CA

CSMA/CA

, N (N /etc/mail/sendmail.cf

sendmail

service sendmail restart

smtp.mydomain.ru

Sendmail B

b.ru

smtp.mydomain.ru

smtp.b.ru

sendmail smtp.mydomain.ru

A 9

/etc/mail/virtusertable

@b.ru%[email protected]

sendmail smtp.b.ru

define(`SMART_HOST',`smtp:smtp.linux.ru')dnl,

smtp.mydomain.ru

smtp.b.ru

Sendmail C

.ru

smtp.mydomain.ru

smtp..ru

sendmail smtp.mydomain.ru

A 7 9

c.ru

useradd ru_c

...

/etc/mail/virtusertable

@c.ruru_c

smtp.mydomain.ru

smtp..ru

Sendmail C

sendmail smtp.c.ru

define(`SMART_HOST',`smtp:smtp.linux.ru')dnl,

fetchmail, /root/fetchmail.cf

poll smtp.mydomain.ru with proto POP3

localdomains c.ru

no envelope

no dns

user "ru_c" with password "password" is

local_user1

local_user2

local_user3

here

smtp.mydomain.ru

smtp..ru

Dynamic Host Configuration Protocol (DHCP) TCP/IP

,


.. , .. . . , , .

: , 2001.

Lectures/LAN-Lec17-TCPIP_Security.ppt

17

..

2007

. ..

, ,

(sniffing)

(man-in-the-middle),

(spoofing)

,

(denial of service, DOS)

, , , , ..

, , ..

,

, -

() ( ),

,

( , )

,

, "" (, public) "" (, private) , "" "",

-

( )

(non-repudiation)

,

,

GenericKey

PrivateKeyA

PublicKeyA

PublicKeyB

A

B

GenericKey

PrivateKeyB

PublicKeyB

PublicKeyA

(integrity) ,

-,

,

GenericKey

PrivateKeyA

PublicKeyA

PublicKeyB

A

B

GenericKey

PrivateKeyB

PublicKeyB

PublicKeyA

-

(confidentiality)

, ,

GenericKey

PrivateKeyA

PublicKeyA

PublicKeyB

A

B

GenericKey

PrivateKeyB

PublicKeyB

PublicKeyA

(authentication) , ,

()

A

B

()

(replay prevention)

, IP-

, , ,

,

M- , S1() S2() , D1() D2()

, ,

A = D1(S1(M)) = D2(S2(M)) = D2(D1(S1(S2(M))))

A = D1(D2(S1(S2(M))))

: -

A M

A B , S1(M)

B A S2(S1(M))

A B D1(S2(S1(M)))

B D2(D1(S2(S1(M)))) = A

S1(M)

A

B

S1()

D1()

M

S2()

D2()

S2(S1(M))

D1(S2(S1(M)))

D2(D1(S2(S1(M))))

M

, ,

(Key Distribution Center, KDC), /

KDC (-)

( )

IPSec

IPSec (IP-Security) IP-, "-"

IP-

Encapsulated Security Payload (ESP) - IP- (Blowfish, 3DES).

Authentication Header (AH) IP- IP

(Security Association, SA) IPSec, () ,

( ) '' '' ( )

(Virtual Private Network, VPN)

Virtual Private Network

IP

,

IP-

IP- ( ); (Network Address Translation, NAT)

IP-

Virtual Private Network

, VPN-1 192.168.1.0/24 192.168.2.0/24, ESP VPN-2, 192.168.2.0/24

VPN- 1

VPN- 2

192.168.2.0/24

192.168.1.0/24

IP1=192.168.1.1

IP2=A.B.C.D

IP1=192.168.2.1

IP2=E.F.G.H

, ,

IP- iptables ( , 2.4 2.6 Linux)

iptables

iptables

IP- , IP-

, ( TCP UDP)

TCP

IP

,

iptables

iptables

iptables (, chains) ,

,

,

iptables

5

1 PREROUTING

2 FORWARD

3 POSTROUTING

4 INPUT

5 OUTPUT

,

TCP/IP

NIC

1

2

3

4

5

iptables

IP- 3 ( )

filter ;

4 INPUT

2 FORWARD

5 OUTPUT

nat (Network Address Translations, NAT);

1 PREROUTING

3 POSTROUTING

5 OUTPUT

mangle ;

iptables

mangle PREROUTING

nat PREROUTING

mangle FORWARD

filter FORWARD

mangle POSTROUTING

nat POSTROUTING

,

mangle PREROUTING

nat PREROUTING

mangle INPUT

filter INPUT

mangle OUTPUT

nat OUTPUT

filter OUTPUT

mangle POSTROUTING

nat POSTROUTING

iptables

iptables

iptables [opts] [-t table] [-com] [parms]

/

//

//

..

filter

iptables-save iptables-restore

iptables

filter

filter

IP- IP-

NIC

TCP TCP

UDP

ICMP ICMP

mac MAC- ,

state

limit

..

iptables

filter

filter

ACCEPT

REJECT , ICMP-

ICMP-

DROP , ICMP-

_

RETURN ,

LOG

iptables

nat

IP-

IP- IP- , ,

NAT

SNAT MASQUERADE IP- /

DNAT IP- ( , )

;

- ,

.. : . :., 2005 .
