Final answer:
The server can refuse the client before or after finishing the 3-way handshake.
Step-by-step explanation:
The answer to the question is No, and they are not mutually exclusive either.
In the TCP/IP protocol suite, the 3-way handshake is a method used by the client and server to establish a connection. During the handshake, the server sends a SYN-ACK (synchronization-acknowledgment) segment to the client after receiving a SYN (synchronization) segment from the client. If the server refuses to establish the connection, it can simply ignore the SYN segment and not send a SYN-ACK.
However, it's important to note that the server can refuse the client after the 3-way handshake is completed as well. This can happen, for example, if the server determines that the client's request is invalid or if the server is experiencing high load and cannot handle additional connections. In this case, the server can send a TCP RST (reset) segment to terminate the connection.