Can you explain the three-way handshake principle in the TCP protocol?

The three-way handshake in TCP is a process that ensures a reliable and synchronized connection between the client and the server.

1. The client sends a segment with the SYN (synchronize) flag to initiate the connection and propose an initial sequence number.
2. The server responds with a segment with SYN and ACK (acknowledge) flags, confirming receipt of the client's SYN and sending its own initial sequence number.
3. The client responds with a segment with the ACK flag, confirming receipt of the server's SYN-ACK.

After this, the connection is considered established, and data transfer begins.

Example:

• Client -> Server: SYN seq=100
• Server -> Client: SYN seq=300, ACK ack=101
• Client -> Server: ACK ack=301

This process ensures the consistency of initial sequence numbers and the readiness of both parties to exchange data.