Based on sliding window protocol

Question

The amount of time it would take to send 500 packets using six packet size window and without sliding window will be,when the time to send in one direction is 5ms?

(A) 3100,5000

(B) 4600,21600

(C) 5000,30000

(D) 30000,5000

Answer 1

to eliminate wrong answers we should first find out time without sliding window,

RTT(tound trip time) = 2 x 5ms = 10ms

for one packet time to send a packet and get its acknowledgement(ack) = 10ms

after getting ack it will send next packet,this will happen 500 times

so time without sliding window = 10 x 500 = 5000ms-----> a and d could be the answers

Now to choose among(a,d) lets go by logic that is, sliding window is created to reduce this time so time by sliding window must be < time without sliding window

hance option a as answer,

but, I will post mathematical answer for option a soon