Question 2 | Stop and wait ARQ

Question

In stop and wait protocol , If the packet size is 1 KB and propogation tme is 15ms the chanel capacity is 10⁹ bits / sec then find :

1. transmission time
2. channel utilisation
3. sender utilisation
4. link utilisation
5. line utilisation
6. What do you account about the difference in channel utilisation and sender utilisation

Answer 1

1) transmission time (1⨉1024⨉8)/10⁹ =8 micro seconds

2) channel utilization =$\frac{1}{1+2(15000/8)}$

                             =1/3751⨉100

                            =0.0266%

link and line utilization same as channel utilization , as it is for stop and wait

link :here

Comments

@srestha,As I know sender utilization=link utilization=line utilization in case of unidirectional transfer.But if transfer is bidirectional and both side sender and receiver are present than sender utilization will be different from link utilization.

verify it.

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how sender utilization can be bidirectional?

how link utilization can be unidirectional?

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@srestha, what I want to say is,In case of bidirectional data transfer, when piggybacked ack is used,then sender utilization will decrease because in this case Rtt=Tt(sendert)+2*Tp+Tt(piggyback ack).

But link utilization will increase becz now data is transferring from both sides.

I think you got my point.