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CSE5501: MOBILE & DISTRIBUTED COMPUTING SYSTEMS

Lecture 3: Wireless LANs

Wireless LANs

• The work on radio-based computer networks goes back to the early

seventies and the work on Aloha network.

• Wireless LANS are providing data rates typically 2 orders of magnitude

higher than outdoor radio. Thus, data rates exceeding 1 Mb/s are quite

common.

• WaveLAN provides peer-to-peer communication in 902-928 MHZ (in the

US) and uses direct sequence spreading with the CSMA/CA (carrier

sense, multiple acess, with collision avoidance) protocol.

• Standards such as IEEE 802.11 are being developed in the US and in

Europe. In general, the goal is to provide data rates exceeding 1 Mb/s and

also to support architectures with infrastructure (base stations) as well as

ad-hoc architectures where the terminals communicate directly with each

other (peer to peer) without the mediation of a fixed base station.

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