What does the term 'SYN_SENT' signify in a TCP session?

The term 'SYN_SENT' in a TCP session indicates that the session is waiting for a response to establish a connection. This state occurs after a client has sent a synchronize (SYN) packet to initiate a connection with a server. In TCP's three-way handshake process, the client sends a SYN packet to request a connection, and the 'SYN_SENT' state signifies that this request has been sent but the client is still waiting for a SYN-ACK (synchronize acknowledgment) response from the server. Once the server receives the SYN request, it responds with a SYN-ACK packet if it is ready to establish the connection, transitioning the session into the next state. Understanding this state is crucial in network communications as it reflects the initial phase of connection establishment in the TCP/IP model.