TCP 3-way handshake is a methodology that is utilized in a TCP or IP network to create a connection between the client and server. It is a three-stage methodology that needs both the server and client to exchange synchronization before the communication process initiates.
. Syn- Used to initiate and establish a connection. It also helps you to synchronize sequence numbers between devices.
. ACK- Helps to confirm to the other side that it has received the SYN.
. FIN- Used to terminate a connection.
In the below diagram, the client and server are advertising their communication. Each TCP header will display the SYN, ACK and SYN/ACK in the connection progresses.