CompTIA Network+ (N10-008) — Question 218

A network client is trying to connect to the wrong TCP port. Which of the following responses would the client MOST likely receive?

Answer options

• A. RST
• B. FIN
• C. ICMP Time Exceeded
• D. Redirect

Correct answer: A

Explanation

When a client tries to connect to an incorrect TCP port, the server typically responds with a RST (reset) packet, indicating that the connection attempt is invalid. The FIN packet is used to terminate an existing connection, ICMP Time Exceeded pertains to routing issues, and Redirect is used by routers to inform hosts of a better route, none of which apply in this scenario.