Question

A disadvantage of the contention approach for LANs, such as CSMA/CD, is the capacity wasted due to multiple stations attempting to access the channel at the same time. Suppose that time is divided into discrete slots, with each of N stations attempting to transmit with probability p during each slot. What fraction of slots are wasted due to multiple simultaneous transmission attempts

Answer 1

The overview of the given problem is outlined in the following segment on the explanation.

Explanation:

The proportion of slots or positions that have been missed due to numerous concurrent transmission incidents can be estimated as follows:

Checking a probability of transmitting becomes "p".

After considering two or even more attempts, we get

Slot fraction wasted,

=
`[1-no \ attempt \ probability-first \ attempt \ probability-second \ attempt \ probability+...]`

On putting the values, we get

=
`1-no \ attempt \ probability-[N* P* probability \ of \ attempts]`

=
`1-(1-P)^(N)-N[P(1-P)^(N)]`

So that the above seems to be the right answer.