In a TCP segment, the field indicates how many bytes the sender can issue to a receiver while acknowledgment for the segment is outstanding. n a TCP segment, the field indicates how many bytes the sender can issue to a receiver while acknowledgment for the segment is outstanding.

Sliding window

Explanation:

A Sliding Window protocol is a feature of packet-based data transmission protocols. Sliding window protocols are used where reliable in-order delivery of packets is required, such as in the data link layer (OSI layer 2) as well as in the Transmission Control Protocol (TCP). They are also used to improve efficiency when the channel may include high latency. Sliding windows are a key part of many protocols. It is a key part of the TCP protocol, which inherently allows packets to arrive out of order, and is also found in many file transfer protocols