Host A and B are communicating over a TCP connection, and Host B has already received from A all bytes up through byte 126. Suppose Host A then sends two segments to Host B back-to-back. The first and second segments contain 70 and 50 bytes of data, respectively. If the first segment, the sequence number is 127, the source port number is 302, and the destination port number is 80. Host B sends an acknowledgement whenever it receives a segment from Host A (no delayed ACKs).

Question

a. In the second segment sent from Host A to B, what are the sequence number, source port number and destination port number?

b. If the first segment arrives before the second segment, in the acknowledgement of the first arriving segment, what is the acknowledgement number, the source port number, and the destination port number?

Answer 1

a. Yes
b. No

Answer 2

In the second segment sent from Host A to B, what are the sequence number, source port number and destination port number

Answer 3

a). Seq=197
source port=302
dest= 80

b). 197, 80, 302