3.5-3 TCP sequence numbers and ACKs (1). Consider the TCP Telnet scenario below (from Fig. 3.31 in text). Why is it that the receiver sends and ACK that is one larger than the sequence number in the received datagram? 3.5-3 TCP sequence numbers and ACKS (1). Consider the TCP Telnet scenario below (from Fig. 3.31 in text). Why is it that the receiver sends andACK that is one larger than the sequence number in the received datagram?Host AHost BUser types 'C'Sed-42, ACK=79, data = 'C'host ACKS receiptof 'C', echoes back °c'Seq=79, ACKE43, data = 'c'host ACKS receiptof echoed 'C'Seq=43, ACK=80simple telnet scenarioO Because TCP sequence numbers always increase by 1, with every new segment, and the TCP receiver always send the sequence number ofthe next expected segmentBecause the send-to receiver segment carries only one byte of data, and after that segment is received, the next expected byte of data is just thenext byte (i.e., has an index that is one larger) in the data stream.

Here the option # (2) is correct option. Acknowledgement number contain the byte number which the receiver is expecting next. Now suppose we send a segment with seq number X and the segment contains y bytes of data then the acknowledgement number send by receiver will contain X+y value ie all the bytes from X has been successfully received. Now expecting x+y byte number data. Thus here since acknowledgement number is 43 and sequence number was 42,it clearly means that only one byte of information was sent