The amount of data the source is capable of sending at one time

The amount of data the destination can process at one time

The number of services included in the TCP segment

The amount of data to be transmitted

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What is Transmission Control Protocol

Transmission Control Protocol (TCP) is a connection-oriented communications protocol that allows computers in a network to send and receive messages. It is the most widely used protocol in networks that employ the Internet Protocol (IP); it is sometimes referred to as TCP/IP when used jointly.