1 Consider the sliding window protocol shown in Fig 3. Does this figure indicate that Go-Back-N is being used, Selective Repeat is being used, or there is not enough information to tell? Explain your answer briefly. receiver sonder send pkto servd pkti send pkt2 send pkt3 (walt) send acko send acki Xloss send ack3 c) Consider Figure 3 again. Suppose the sender and receiver windows are of size N = 4 and suppose the sequence number space goes from 0 to 15. Show the position of the sender and receiver windows over this sequence number space at time t d) Give a list of all possible future events at the sender resulting from the ACKs currently propagating from receiver to sender at time t. For each of these events, indicate the action take at the sender (only). e) Suppose that it take 1 ms to send a packet, with a 10 ms one-way propagation delay between the sender and receiver. The sliding windows size is again N= 4. What is the channel/link utilization