Suppose A is connected to B via an intermediate router R, as in the previous problem. The A–R link is instantaneous, but the R–B link transmits only one packet each second, one at a time (so two packets take 2 seconds). Assume A sends to B using the sliding window protocol with SWS = 4.

For time = 0, 1, 2, 3, 4, state what packets arrive at and are sent from A and B. How large does the queue at R grow?