What is the main role of the TCP protocol in network communication?

The main role of the TCP (Transmission Control Protocol) in network communication is to ensure reliable, ordered, and error-free data transfer between two nodes in a network.

TCP is responsible for:

• Connection establishment: data transfer occurs only after establishing a connection (three-way handshake).
• Reliability: guarantees delivery of all data packets, retransmitting lost packets.
• Ordering: data is delivered in the order it was sent.
• Flow control: regulates the transmission rate to prevent overwhelming the receiver.
• Congestion control: adjusts the transmission speed based on network conditions.

Unlike UDP, TCP provides reliable communication, which is crucial for applications where data loss is unacceptable (e.g., web servers, databases, email).

Example: when loading a web page, TCP guarantees that all parts of the page arrive correctly and in the right order.