What are the three steps of a TCP handshake?

The three steps of a TCP handshake are SYN, SYN-ACK, and ACK. This process is essential for establishing a reliable connection between a client and a server before they begin to exchange data.

1. SYN: The client initiates the connection by sending a Synchronize (SYN) packet to the server, indicating that it wants to establish a connection and providing its initial sequence number.

2. SYN-ACK: The server responds with a Synchronize-Acknowledge (SYN-ACK) packet. This packet serves a dual purpose: it acknowledges the receipt of the client's SYN packet and also includes the server’s own SYN packet, along with its own initial sequence number.

3. ACK: Finally, the client sends an Acknowledge (ACK) packet back to the server, confirming that it received the server's SYN-ACK packet. At this point, the TCP connection is fully established, and the two parties can begin to communicate.

This three-step process ensures that both the client and server are synchronized and have the proper sequence numbers for tracking the data that will be sent, which is critical in maintaining data integrity during transmission.