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| n |
Traffic
services
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– |
Asynchronous
Data Service (mandatory)
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n |
exchange
of data packets based on “best-effort”
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n |
support
of broadcast and multicast
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– |
Time-Bounded
Service (optional)
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n |
implemented
using PCF (Point Coordination Function)
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| n |
Access
methods
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– |
DCF
CSMA/CA (mandatory)
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n |
collision
avoidance via randomized „back-off“ mechanism
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n |
minimum
distance between consecutive packets
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n |
ACK
packet for acknowledgements (not for broadcasts)
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– |
DCF
w/ RTS/CTS (optional)
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n |
Distributed
Foundation Wireless MAC (DFWMAC)
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n |
avoids
hidden terminal problem
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– |
PCF
(optional)
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n |
access
point polls terminals according to a list
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