GATE | GATE-CS-2015 (Set 3) | Question 65

Consider the following statements.

I. TCP connections are full duplex.
II. TCP has no option for selective acknowledgment
III. TCP connections are message streams.

(A) Only I is correct
(B) Only I and II are correct
(C) Only II and III are correct
(D) All of I, II and III are correct


Answer: (A)

Explanation:

1. In TCP, as sender and receiver can send segments at the same time, It is FULL-DUPLEX.
2. TCP has options for selective acknowledgement. With selective acknowledgments (SACKs), the data receiver can inform the sender about all segments that have arrived successfully, so the sender need retransmit only the segments that have actually been lost.
3. As each BYTE is counted in TCP segment, and Sequence number of First BYTE is kept into header, TCP is BYTE stream protocol.

So, only 1^st is correct and other incorrect.

Reference :
https://tools.ietf.org/html/rfc2018

This solution is contributed by sandeep pandey.

Quiz of this Question