TCP (Transmission Control Protocol) is a widely-used transport layer protocol that provides reliable, stream-oriented communication over an IP network. It is designed to ensure that data is delivered in the correct order and without errors.
The mechanisms of TCP include:
Sequence numbers: Each byte of data sent over a TCP connection is assigned a unique sequence number. This allows the receiving end to reassemble the data in the correct order.
Acknowledgments: The receiving end of a TCP connection sends an acknowledgement (ACK) message back to the sender to confirm that it has received the data. The sender will retransmit any data that has not been acknowledged.
Flow control: TCP uses a sliding window mechanism to regulate the flow of data and prevent the sender from overwhelming the receiver.
Error checking: TCP includes error checking mechanisms to detect and recover from errors in the transmission of data. This includes checksums to detect corrupted data and retransmission of data that is not correctly received.
Connection establishment and termination: TCP includes a three-way handshake mechanism for establishing a connection, and a four-way mechanism for terminating a connection. This ensures that both ends of the connection are ready to communicate and that the connection is properly closed when it is no longer needed.