Which of the following is a 16-bit field that identifies the source port number of the application program in the host that is sending the segment?

Which of the following is a 16-bit field that identifies the source port number of the application program in the host that is sending the segment?
A . Sequence Number
B . Header Length
C . Acknowledgment Number
D . Source Port Address

View Answer

Answer: D

Explanation:

Source Port Address is a 16-bit field that identifies the source port number of the application program in the host that is sending the segment. Answer option C is incorrect. This is a 32-bit field that identifies the byte number that the sender of the segment is expecting to receive from the receiver. Answer option B is incorrect. This is a 4-bit field that defines the 4-byte words in the TCP header. The header length can be between 20 and 60 bytes. Therefore, the value of this field can be between 5 and 15. Answer option A is incorrect. This is a 32-bit field that identifies the number assigned to the first byte of data contained in the segment.