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Transmission Control Protocol (TCP)

Transmission Control Protocol (TCP) is a communication protocol that ensures data is delivered accurately. It does this by breaking messages down into small packets and sending them to their destination, where they are later rebuilt.

TCP Handshake

TCP Three-Way Handshake refers to the three steps needed to establish a TCP connection.

• The client sends the server a "synchronize" (SYN) message with its own sequence number (x), which the server receives.
• The server responds with a "synchronize-acknowledgement" (SYN-ACK) message with its own sequence number (y) and acknowledgement number (x + 1), which the client receives.
• The client replies with an "acknowledgement" (ACK) message with the acknowledgement number (y + 1), which the server receives and doesn't meed tp reply.