Applied Test Series

Question

Consider the effect of using additive increase multiplicative decrease(AIMD) on a line with propagation delay of 10ms.The receive window is 24KB and the maximum segment size is 2KB. How long does it take to completely send full window size segment in ms initial threshold of 20KB?

 

Answer 1

First transmission: 2KB

Second transmission: 4KB

Third transmission: 8 KB

Fourth transmission: 16 KB

Fifth transmission: 20 KB [ Threshold reached]

Sixth transmission: 22 KB [ Congestion avoidance phase starts]

Seventh transmission: 24 KB

It takes 7 round trip time.

RTT = 2 *Tp = 10 ms = 20 ms

So 7 RTT = 20 x  7 = 140 ms