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Summary: mac protocol features – Siemens IEEE802.11 User Manual

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© Siemens, 2002

Summary: MAC Protocol Features

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Distributed Coordination Function (DCF) provides efficient
medium sharing
– Use Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
– MAC uses the PHY layer Clear Channel Assessment (CCA) function for

CSMA/CA

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Robust for interference
– CSMA/CA + ACK for unicast frames, with MAC level recovery
– CSMA/CA for broadcast frames

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Virtual carrier sense function provided to protect against hidden nodes

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Includes fragmentation to cope with different PHY characteristics

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Point Coordination Function (PCF) option for time bounded data

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Frame formats to support multiple configurations and roaming