3.2. The Transmission Control Protocol

TCP is the Transport layer of the protocol and serves to ensure a reliable, verifiable data exchange between hosts on a network. TCP breaks data into pieces, wraps the pieces with the information needed to identify it as a piece of the original message, and allows the pieces to be reassembled at the receiving end of the communications link. The wrapped and bundled pieces are called datagrams. Datagrams are also referred to as segments for TCP due to the way it often splits the original data into more manageable chunks. The most important information in the header includes the source and destination port numbers, a sequence number for the datagram, and a checksum.

The source port number and the destination ...

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