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| n |
Channel
Access Control (CAC)
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– |
assure
that terminal does not access forbidden channels
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– |
priority
scheme, access with EY-NPMA
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| n |
Priorities
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– |
5
priority levels for QoS support
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– |
QoS
is mapped onto a priority level with the help of the packet
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lifetime
(set by an application)
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n |
if
packet lifetime = 0 it makes no sense to forward the packet to the
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receiver
any longer
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n |
standard
start value 500ms, maximum 16000ms
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n |
if a
terminal cannot send the packet due to its current priority, waiting
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time
is permanently subtracted from lifetime
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n |
based
on packet lifetime, waiting time in a sender and number of hops
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to
the receiver, the packet is assigned to one out of five priorities
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n |
the
priority of waiting packets, therefore, rises automatically
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