URGENT!!

Question $1(30$ Points$)$

Consider the transmission of a file of size $F[$Byte$]$ over a packet$-$

switched network route consisting of five links $($i$.$e$.,$ traversing four

packet$-$switching routers$).$ Each link has transmission bit rate $R$

$[$bit$/$s$]$ and propagation delay $].$ Suppose queueing delays and

processing delays are negligible. We employ a reliable transmission

protocol with acknowledgements.

A$.$ Suppose the entire file is sent as one large message and one

acknowledgement is sent for the entire file. The

acknowledgement is very small, i$.$e$.,$ has negligible transmission

time. What is the delay from the start of the transmission at the

sender to the receipt of the acknowledgement at the sender$?$

B$.$ Suppose the file is partitioned into segments of size $P[$Byte$]$ with

$\frac{F}{P}$ being an integer and a very small acknowledgement is sent

for each segment. Suppose further that we employ a send$-$and$-$

wait $($stop$-$and$-$wait$)$ reliable transport protocol, i$.$e$.,$ only one

unacknowledged segment is allowed to be out in the network at

any point in time. What is the delay from the start of the

transmission at the sender to the receipt of the

acknowledgement for the last segment at the sender$?$