Access Point

IEEE 802.11

Principais Aplicações

Padrões IEEE 802.11

802.11a 5GHz, 54Mbps 802.11b 2.4GHz, 11Mbps 802.11c Protocolo para bridges 802.11d World Mode (Europa 20 dB, EUA-BR 36dB 802.11e Qualidade de Serviço 802.11f Inter-Access Point Protocol 802.11g 2.4GHz, 54Mbps, modulação digital OFDM 802.11h Seleção dinâmica de frequência 802.11i Autenticação e Segurança

Access Point

Short for Access Point, a hardware device or a computer's software that acts as a communication hub for users of a wireless device to connect to a wired LAN.

APs are important for providing heightened wireless security and for extending the physical range of service a wireless user has access to.

Infrastructure Mode

An 802.11 networking framework in which devices communicate with each other by first going through an Access Point (AP).

In infrastructure mode, wireless devices can communicate with each other or can communicate with a wired network.

When one AP is connected to wired network and a set of wireless stations it is referred to as a Basic Service Set (BSS).

Infrastructure Mode

An Extended Service Set (ESS) is a set of two or more BSSs that form a single subnetwork.

Most corporate wireless LANs operate in infrastructure mode because they require access to the wired LAN in order to use services such as file servers or printers.

Ad-hoc Mode

An 802.11 networking framework in which devices or stations communicate directly with each other, without the use of an access point (AP).

Ad-hoc mode is also referred to as peer-to-peer mode or an Independent Basic Service Set (IBSS).

Ad-hoc mode is useful for establishing a network where wireless infrastructure does not exist or where services are not required.

802.11

802.11 refers to a family of specifications developed by the IEEE for wireless LAN technology.

802.11 specifies an over-the-air interface between a wireless client and a base station or between two wireless clients.

The IEEE accepted the specification in 1997.

Specifications in the 802.11 family –802.11 e 802.11a 802.11 -- applies to wireless LANs and provides 1

or 2 Mbps transmission in the 2.4 GHz band using either frequency hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS).

802.11a -- an extension to 802.11 that applies to wireless LANs and provides up to 54 Mbps in the 5GHz band. 802.11a uses an orthogonal frequency division multiplexing encoding scheme rather than FHSS or DSSS.

802.11b

802.11b (also referred to as 802.11 High Rate or Wi-Fi) -- an extension to 802.11 that applies to wireless LANS and provides 11 Mbps transmission (with 2 and 1 Mbps) in the 2.4 GHz band.

802.11b

802.11b uses only DSSS.

802.11b was a 1999 ratification to the original 802.11 standard, allowing wireless functionality comparable to Ethernet.

Access Point

Short for Access Point, a hardware device or a computer's software that acts as a communication hub for users of a wireless device to connect to a wired LAN.

APs are important for providing heightened wireless security and for extending the physical range of service a wireless user has access to.

Infrastructure Mode

An 802.11 networking framework in which devices communicate with each other by first going through an Access Point (AP).

In infrastructure mode, wireless devices can communicate with each other or can communicate with a wired network.

When one AP is connected to wired network and a set of wireless stations it is referred to as a Basic Service Set (BSS).

Infrastructure Mode

An Extended Service Set (ESS) is a set of two or more BSSs that form a single subnetwork.

Most corporate wireless LANs operate in infrastructure mode because they require access to the wired LAN in order to use services such as file servers or printers.

Ad-hoc Mode

An 802.11 networking framework in which devices or stations communicate directly with each other, without the use of an access point (AP).

Ad-hoc mode is also referred to as peer-to-peer mode or an Independent Basic Service Set (IBSS).

Ad-hoc mode is useful for establishing a network where wireless infrastructure does not exist or where services are not required.

802.11

802.11 refers to a family of specifications developed by the IEEE for wireless LAN technology.

802.11 specifies an over-the-air interface between a wireless client and a base station or between two wireless clients.

The IEEE accepted the specification in 1997.

Specifications in the 802.11 family –802.11 e 802.11a 802.11 -- applies to wireless LANs and provides 1

or 2 Mbps transmission in the 2.4 GHz band using either frequency hopping spread spectrum (FHSS) or direct sequence spread spectrum (DSSS).

802.11a -- an extension to 802.11 that applies to wireless LANs and provides up to 54 Mbps in the 5GHz band. 802.11a uses an orthogonal frequency division multiplexing encoding scheme rather than FHSS or DSSS.

802.11b

802.11b (also referred to as 802.11 High Rate or Wi-Fi) -- an extension to 802.11 that applies to wireless LANS and provides 11 Mbps transmission (with a fallback to 5.5, 2 and 1 Mbps) in the 2.4 GHz band.

802.11b uses only DSSS. 802.11b was a 1999 ratification to the original 802.11 standard, allowing wireless functionality comparable to Ethernet.

802.11b (Wi-Fi)

Data Rate: Up to 11Mbps in the 2.4GHz band Modulation scheme: DSSS with CCK Security: WEP & WPA

Products that adhere to this standard are considered "Wi-Fi Certified." Not interoperable with 802.11a. Requires fewer access points than 802.11a for coverage of large areas.

Offers high-speed access to data at up to 300 feet from base station.

14 channels available in the 2.4GHz band (only 11 of which can be used in the U.S. due to FCC regulations) with only three non-overlapping channels.

IEEE 802.11g

Data Rate: Up to 54Mbps in the 2.4GHz band Modulation Scheme: OFDM above 20Mbps, DSSS with CCK below

20Mbps WEP & WPA. Security: WEP & WPA

Pros/Cons & More Info: Products that adhere to this standard are considered "Wi-Fi

Certified." May replace 802.11b. Improved security enhancements over 802.11. Compatible with 802.11b. 14 channels available in the 2.4GHz band (only 11 of which can be used in the U.S. due to FCC regulations) with only three non-overlapping channels.

IEEE 802.16 (WiMAX)

Specifies WiMAX in the 10 to 66 GHz range. OFDM DES3 and AES Commonly referred to as WiMAX or less

commonly as WirelessMAN or the Air Interface Standard,

IEEE 802.16 is a specification for fixed broadband wireless metropolitan access networks (MANs).

IEEE 802.16a (Wi-MAX)

Added support for the 2 to 11 GHz range. OFDM DES3 and AES Commonly referred to as WiMAX or less

commonly as WirelessMAN or the Air Interface Standard,

IEEE 802.16 is a specification for fixed broadband wireless metropolitan access networks (MANs).

Bluetooth

Up to 2Mbps in the 2.45GHz band. FHSS. PPTP, SSL or VPN. No native support for IP, so it does not

support TCP/IP and wireless LAN applications well.

Not originally created to support wireless LANs. Best suited for connecting PDAs, cell phones and PCs in short intervals.

OFDM

Short for Orthogonal Frequency Division Multiplexing, an FDM modulation technique for transmitting large amounts of digital data over a radio wave.

OFDM works by splitting the radio signal into multiple smaller sub-signals that are then transmitted simultaneously at different frequencies to the receiver.

OFDM reduces the amount of crosstalk in signal transmissions. 802.11a WLAN, 802.16 and WiMAX technologies use OFDM.

FHSS

Acronym for frequency-hopping spread spectrum. FHSS is one of two types of spread spectrum radio, the other being direct-sequence spread spectrum.

FHSS is a transmission technology used in WLAN transmissions where the data signal is modulated with a narrowband carrier signal that "hops" in a random but predictable sequence from frequency to frequency as a function of time over a wide band of frequencies.

FHSS

The signal energy is spread in time domain rather than chopping each bit into small pieces in the frequency domain.

This technique reduces interference because a signal from a narrowband system will only affect the spread spectrum signal if both are transmitting at the same frequency at the same time.

If synchronized properly, a single logical channel is maintained.

FHSS

The transmission frequencies are determined by a spreading, or hopping, code.

The receiver must be set to the same hopping code and must listen to the incoming signal at the right time and correct frequency in order to properly receive the signal.

Current FCC regulations require manufacturers to use 75 or more frequencies per transmission channel with a maximum dwell time (the time spent at a particular frequency during any single hop) of 400 ms.

DSSS

Acronym for direct-sequence spread spectrum. DSSS is one of two types of spread spectrum radio, the other being

frequency-hopping spread spectrum.

DSSS is a transmission technology used in WLAN transmissions where a data signal at the sending station is combined with a higher data rate bit sequence, or chipping code, that divides the user data according to a spreading ratio.

The chipping code is a redundant bit pattern for each bit that is transmitted, which increases the signal's resistance to interference.

If one or more bits in the pattern are damaged during transmission, the original data can be recovered due to the redundancy of the transmission.

CCK - Complementary Code Keying Short for Complementary Code Keying, a

set of 64 eight-bit code words used to encode data for 5.5 and 11Mbps data rates in the 2.4GHz band of 802.11b wireless networking.

The code words have unique mathematical properties that allow them to be correctly distinguished from one another by a receiver even in the presence of substantial noise and multipath interference.

CCK - Complementary Code Keying CCK works only in conjunction with the DSSS

technology that is specified in the original 802.11 standard.

It does not work with FHSS. CCK applies sophisticated mathematical formulas to

the DSSS codes, permitting the codes to represent a greater volume of information per clock cycle.

The transmitter can then send multiple bits of information with each DSSS code, enough to make possible the 11Mbps of data rather than the 2Mbps in the original standard.

CSMA/CA

Short for Carrier Sense Multiple Access/Collision Avoidance, a network contention protocol that listens to a network in order to avoid collisions.

Unlike CSMA/CD that deals with network transmissions once collisions have been detected.

CSMA/CA

CSMA/CA contributes to network traffic because, before any real data is transmitted, it has to broadcast a signal onto the network in order to listen for collision scenarios and to tell other devices not to broadcast.

L-G700AP  >  High Speed 2.4GHz (802.11g) Wireless Access Point

L-G700AP  >  High Speed 2.4GHz (802.11g) Wireless Access Point Product Features:

Up to 54Mbps*

WPA for Enhanced Wireless Security

Quickly Add Wireless Access to Your Network

Web-based Configuration and Management

Product Features:

DWL-2100AP  >  High Speed 2.4GHz (802.11g) Wireless 108Mbps Access Point

Up to 108Mbps* WPA & 802.1x Authentication SNMP Management Software Included Also Work as Point-To-Point Bridge, Point-to-

Multipoint Bridge, Repeater, Wireless Client.

Wireless G USB Adapter

Wireless G USB Adapter

Easily Connect to Your Wireless Network from Your Desktop or Notebook PC

Works with 802.11g and 802.11b Wireless Networks

Check E-mail, Surf the Web, and Chat with Friends and Family Online

DWL-G122  >  High Speed 2.4GHz (802.11g) Wireless USB Adapter

DWL-G122  >  High Speed 2.4GHz (802.11g) Wireless USB Adapter Product Features: Up to 54Mbps* 802.11g Standard, 802.11b Compatible Protect Your Network with WPA and 802.1x

Security Quick and Easy Setup

DI-524  >  High Speed 2.4GHz (802.11g) Wireless Router

DI-524  >  High Speed 2.4GHz (802.11g) Wireless Router Product Features:

Up to 54Mbps* Advanced Firewall & Parental Control  Quick and Easy Setup 802.11g Standard, 802.11b Compatible

WNA-1330  >  Wireless G Notebook Adapter

WNA-1330  >  Wireless G Notebook Adapter Product Features:

Easily Connect to Your Wireless Network from Your Notebook PC.

Works with 802.11g and 802.11b Wireless Networks.

Check E-mail, Surf the Web, and Chat with Friends and Family Online.

DSL-2640B  >  ADSL2/2+ Modem with Wireless Router

DSL-2640B  >  ADSL2/2+ Modem with Wireless Router Product Features:

Supports The Latest ADSL Standards for Superior Performance.

Access a High-Speed DSL Connection and Share The Internet.

Connect Multiple Computers and Share Files - Wired or Wirelessly.

WDA-1320  >  Wireless G Desktop Adapter

WDA-1320  >  Wireless G Desktop Adapter

Product Features:

Easily Connect to Your Wireless Network from Your Desktop PC.

 Works with 802.11g and 802.11b Wireless Networks.

 Check E-mail, Surf the Web, and Chat with Friends and Family Online.

DWL-G510  >  High Speed 2.4GHz (802.11g) Wireless PCI Adapter

DWL-G510  >  High Speed 2.4GHz (802.11g) Wireless PCI Adapter Product Features:

Up to 54Mbps*. 802.11g Standard, 802.11b Compatible.  Great for Video Streaming.  Increased Security with 802.1x and WPA**

DWL-G630  >  High Speed 2.4GHz (802.11g) Wireless Cardbus Adapter

DWL-G630  >  High Speed 2.4GHz (802.11g) Wireless Cardbus Adapter Product Features:

Up to 54Mbps* Great for Video Streaming 802.11g Standard, 802.11b Compatible Increased Wireless Security with WPA and

802.1x**.

DP-G310  >  Wireless G USB Print Server

DP-G310  >  Wireless G USB Print Server

Product Features:

Supports USB 2.0 802.11g Standard, 802.11b Compatible Easy Web-based Set up and Configuration

DNS-G120  >  Wireless G Network Storage Adapter

DNS-G120  >  Wireless G Network Storage Adapter Product Features:

Wirelessly Connect USB Storage to the Network.

Built-in FTP Server** for Accessing Files over the Internet.

Use Your Existing USB Drives Without Reformatting

DVG-G1402S  >  Wireless Broadband VoIP Router

DVG-G1402S  >  Wireless Broadband VoIP Router Product Features:

802.11g Wireless Connectivity. Connect Up To 2 VoIP Lines.  Integrated QoS To Prevent Dropped Calls

And Deliver Superior Voice Quality.

DIR-330  >  Wireless G Firewall/VPN 8 Router, 4-port Switch

DIR-330  >  Wireless G Firewall/VPN 8 Router, 4-port Switch Product Features: Share a High-Speed Internet Connection. Support and Manage up to 8 VPN

Configurations. Simple-to-Deploy Routing, VPN, and Firewall

Solution. Enterprise-Class Security Protects Your

Network from Online Intruders and Potential Attacks.

DPG-2100  >  Wireless Presentation Gateway

DPG-2100  >  Wireless Presentation Gateway Product Features:

Quickly Switch between Presenters Using Separate Computers.

Works with 802.11g and 802.11b Wireless Enabled PCs to Deliver Your Presentation.

Connect to Your Projectorby cable.

DBT-120  >  Wireless Bluetooth 2.0 USB Adapter

DBT-120  >  Wireless Bluetooth 2.0 USB Adapter Product Features:

Sync Data between Your Bluetooth PDA, Mobile Phone, and PC.

Secure Encyption for Enhanced Network Protection.

Experience The Convenience of Bluetooth Headphones, Cameras and Keyboards.

Works with PC & Mac2.

AnyCom Bluetooth Access Point

The ANYCOM EDR-AP Bluetooth is an access point for professional applications.

It enables mobile devices equipped with Bluetooth technology like mobile phones, PDAs or PCs to connect wirelessly to local networks and the Internet.

AnyCom Bluetooth Access Point The ANYCOM EDR-AP is equipped with the

latest Bluetooth 2.0 Standard including the Enhanced-Data-Rate (EDR) specification.

This allows data transmission rates up to 1, 2 MB/s and several mobile users to connect to it simultaneously without delay.

AnyCom Bluetooth Access Point

As a class 1 device the covering range is up to 300 feet (100 meter) but the beaming power can be reduced for special applications.

AnyCom Bluetooth Access Point Extensive Security and Management-

Functionalities like DHCP, SNMP and Radius Server suits the ANYCOM EDR-AP access point also into complex network environments.

With the PPPoE protocol the ANYCOM EDR-AP can also be used as ADSL gateway.

AnyCom Bluetooth Access Point

The ANYCOM EDR-AP on embedded Linux operating system, with Flash memory for easy software upgrades, and built-in Web server and Web interface for quick installation, and remote configuration and management.