Question

Two CSMA/CD stations are each trying to transmit long files. After each frame is sent, they contend for the channel using binary exponential backoff algorithm. What is the probability that the contention ends on round k, and what is the mean number of rounds per contention period?

Answer 1

We know that the collision occurs in round 1 so, the probability of transmission in round 1 is zero.

So, The probability that the contention ends in round k is :-

The mean number of rounds per contention period is nothing but the expectation which is given by :-

$\sum_kk.P_k$