TCP i.e.Transmission Control Protocol is one of main Transport Layer protocol which provides reliable, connection-oriented communication over IP networks between two end stations. When data is provided to the IP protocol, it encapsulates them in IP datagrams. TCP is defined by the Internet Engineering Task Force (IETF) in the Request for Comment (RFC) standards document number 793.With TCP protocol applications can communicate securely independent from the lower layers. The Layer 3 devices (Router/Layer 3 Switch etc.) only need to route data as datagrams, without concerning about data control since congestion control and monitoring is performed by the transport layer.
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