When a client requests a connection, which type of packet do they send?

When a client requests a connection, they initiate the process by sending a SYN packet. This packet is part of the TCP (Transmission Control Protocol) three-way handshake, which establishes a reliable connection between a client and a server.

The SYN packet serves as a request to begin the connection process, indicating that the client wants to establish a session with the server. When the server receives the SYN packet, it typically responds with a SYN-ACK packet, acknowledging the request for connection. The client then responds with an ACK packet to complete the handshake and finalize the connection setup. This method ensures that both the client and server are ready to communicate before any actual data is transmitted, which is crucial for maintaining data integrity and reliability.

In contrast, other packet types such as ACK packets, ECHO packets, and RESET packets serve different purposes in network communication. ACK packets are used to acknowledge the receipt of data, ECHO packets are often associated with testing connectivity (like in a ping command), and RESET packets are utilized to abruptly terminate a connection. None of these serve the purpose of initially requesting a connection, which is why the SYN packet is the correct answer in this context.