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(a) When a flow which is MSI 60ms is admitted
(b) When an additive flow which is MSI 90ms is admitted
(c) When an additive flow which is MSI 30ms is admitted
Fig. 2. The Si allocation of reference scheduler
for the next transmission. The start value of TXOP for QST A i is mT D i which
guarantees the transmission of a Maximum MSDU Size frame. The increasing
rate for the token occurring in every interval is Rate i , which means that TXOP
Timer is increased as much as mTD in every interval to guarantee average data
transmission in mSI. TXOP timer for QST A i can increase upto MTD i which
is the time necessary to transmit a maximum burst size. TXOP i is determined
between mT D i and MTD i of QST A i which are calculated as follows.
mT D i =max( M i
R i
MTD i = ΣMBS i
R i
mT D i
mSI i
Rate i =
2nd Step : SI allocation
Reference scheduler is inecient because all the station have the same SI. SI of
SETT-EDD is variable because it uses work-conserving method as follows. In
SETT-EDD, if the channel is idle for PIFS duration, the scheduler starts to poll
the station which satisfies the following equation.
t pre + mSI i ≤ t ≤ t pre + MSI i
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