Question

Which field in a Transmission Control Protocol (TCP) header provides the next expected segment?

Answer 1

In a Transmission Control Protocol (TCP) header next  Expected segment is provided by Acknowledgment Number

Explanation:

• TCP is one of the main protocols of the Internet protocol suite. It originated in the initial network implementation in the Internet Protocol.

• The fields in TCP Segment Header are Source Port, Destination Port, Sequence Number, Acknowledgement Number, Header Length, Flags, Window Size, TCP Checksum and Urgent Pointer.
• The Acknowledgment Number is a  32 Bit number field which indicates the next sequence number that the sending device is expecting from the other device.
• The SYN packets consume one sequence number, so actual data will begin at ISN+1. The sequence number is the byte number of the first byte of data in the TCP packet sent.

• If the acknowledgment flag is set in the flags field, the acknowledgment number field holds the sequence number of the next byte that the receiver expects.