Suppose a shared ethernet link L, in which for nodes T1-T4 and a router R are connected:
--------------------------- R
| | | |
T1 T2 T3 T4
L has bit-rate C=100 Mbps
, and propagation delay is PROP = 10 msec
.
Every node transmits packet with probability Pb = 10%
. The mean packet length is P(length)=100 KBytes
Note that ethernet uses CSMA/CA
What is the average time for a node to transmit on the shared medium?
What I've tried:
We know that on carrier sense WAIT_BEFORE_RETRANSMITTING = 5*PROP = 50 ms
.
We also know transmission_delay = P(length) / C = 8 ms
in our case
So, based on those results, I suppose that the average time for a node to transmit on the shared medium is 50 + 8 = 58 ms