• Mini slot time: time duration
that is at least as big as two propagation delay
• Mini slot is basis for
contention resolution
• Backoff algorithm: The first retransmission
time involves zero or one minislot
times, the second involves
0,1,2,3 minislot times and each additional slot
retransmission extends the range
the range by a factor of 2 until the maximum
range of 1210
• The average number of minislots
in a contention period is approximately e=2.71
therefore the fraction
• The average number of minislots
in a contention period is approximately e=2.71
therefore the fraction of time
that the channel is busy transmitting frames is
L/R = 1
L/R+tprop+2etprop 1+6.44a
Where a=tprop R/L
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