Interactive end-of-chapter exercises


Supplement to Computer Networking: A Top Down Approach 8th Edition


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TCP sequence and ACK numbers with segment loss

Consider the figure below in which a TCP sender and receiver communicate over a connection in which the sender->receiver segments may be lost. The TCP sender sends an initial window of 5 segments. Suppose the initial value of the sender->receiver sequence number is 24 and the first 5 segments each contain 502 bytes. The delay between the sender and receiver is 7 time units, and so the first segment arrives at the receiver at t=8. As shown in the figure below, 3 of the 5 segment(s) are lost between the segment and receiver.





Question List


1. Give the sequence numbers associated with each of the 5 segments sent by the sender. Format your answer as: a,b,c,...

2. Give the ACK numbers the receiver sends in response to each of the segments. If a segment never arrives use 'x' to denote it, and format your answer as: a,b,c,...




Solution


1. The sender's sequence numbers are: 24,526,1028,1530,2032

2. The receiver's ACKs are: 526,x,x,x,526



That's incorrect

That's correct

The answer was: 24,526,1028,1530,2032

Question 1 of 2

The answer was: 526,x,x,x,526

Question 2 of 2

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