What process is used to establish a TCP connection?
The correct answer and explanation is :
Correct Answer:
The process used to establish a TCP connection is the three-way handshake.
Explanation (300 words):
The Transmission Control Protocol (TCP) is a connection-oriented protocol, which means that a reliable connection must be established between two devices before data can be exchanged. This is achieved using the three-way handshake, a synchronization process that ensures both parties are ready to transmit and receive data.
Here’s how the three-way handshake works:
- SYN (Synchronize):
The client sends a TCP segment with the SYN flag set to the server, indicating a request to start communication. This segment also includes an initial sequence number (ISN) that the client plans to use for its data transmission. - SYN-ACK (Synchronize-Acknowledge):
The server responds with a segment that has both the SYN and ACK flags set. The SYN flag indicates the server’s readiness to establish communication, and it includes its own ISN. The ACK flag acknowledges the client’s SYN by confirming the received sequence number (client’s ISN + 1). - ACK (Acknowledge):
The client sends a final segment with the ACK flag set, acknowledging the server’s ISN (server’s ISN + 1). Once this step is completed, the connection is established, and both parties can begin to exchange data.
This handshake ensures synchronization of sequence numbers and agreement on connection parameters, providing a reliable path for data exchange. It also helps protect against spoofing and packet loss by confirming that both the client and server are reachable and ready.
The three-way handshake is foundational for services like HTTP, FTP, and email, which rely on reliable data delivery. By establishing a connection before transmitting data, TCP ensures data integrity, order, and flow control, distinguishing it from connectionless protocols like UDP.