Wireless ATMFrancine Lalooses

David Lancia

Arkadiusz Slanda

Donald Traboini

Lalooses*Lancia*Slanda*Traboini

Overview

• What is ATM?

• The Promise of Wireless ATM

• Transition from Wired ATM

• Advantages and Disadvantages

• Research and Implementations

• Goals of the Project

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What is ATM?

Asynchronous Transfer Mode (ATM)• A networking technology developed by the

telephone companies to handle all types of data using fixed 53-byte cells, or packets.

• Creates virtual point-to-point circuit connections between the source and the destination.

• Data rates from 25 to 622 Mbps.

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What is ATM?

• The small cell size allows ATM to transmit video, audio, and computer data over the same network, while guaranteeing a preset QoS level for each.

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The Promise of W-ATM

• Extension of LAN for mobile user

• Simplified wiring and configuration

• Provide high-speed data access for users without need for a new wired infrastructure

• Create unforeseen opportunities for future applications

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W-ATM

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Transition Issues

• Physical Layer• Infrared vs. Radio

• Circuit-switched vs. Packet-switched

• Channel Coding

• Multiple Antennas

• Operating Frequency• Licensed vs. Unlicensed Frequency

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Operating Frequency

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Transition Issues

• Data Link Layer• Encapsulation

• Header Compression

• ARQ (Automatic Repeat Request) vs. FEC (Forward Error Correction)

• Quality-of-Service Issues

• Split Functionality

• An Example Protocol

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Proposed Architecture

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Advantages of W-ATM

• Benefits of ATM made mobile• Free to roam

• Flexible bandwidth allocation

• Efficient multiplexing of traffic

• Availability of existent ATM switching

• Flexibility of reusing same frequency

• Soft handoff without any data loss

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W-ATM Base Stations

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Disadvantages of W-ATM

• Delay to multi-path interference

• Hop-by-hop routing method not adequate

• Virtual connection takes longer

• Poor physical level characteristics• High noise interference

• Finding a suitable wireless channel

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Research and ImplementationMagic WAND (Wireless ATM Network Demonstrator)

• Goals: • To specify and implement W-ATM• To promote the standardization of W-ATM• To demonstrate that W-ATM is technically

feasible

• Achievements• Specifications of W-ATM• Standardization

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Magic WAND

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Goals

• Simulate the effects of noise on choosing a channel

• Analyze the effects of mobility on a wireless ATM network