TCPIPTutorial

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  In the TCP/IP protocol suite, TCP is the intermediate layer between IP below it, and an application above it. Using TCP, applications on networked hosts can establish reliable connections to one another. The protocol guarantees in-order delivery of data from the sender to the receiver Streams of data called segments are used by TCP peers to speak to each other. The segments can be quite large, so TCP breaks up the segments into smaller units of data. These units are encapsulated in the TCP packet that is passed to the IP protocol. Each unit of data is assigned a sequence number, which becomes part of the TCP packet. At the receiving end, the TCP module uses the sequence numbers in the packet to reconstruct the user data in the correct order.