A network administrator wishes to ensure there are no unnecessary open communication paths into a server.
Using a port scanner, the administrator finds that ports are reported as closed.
Which of the following BEST explains this response?
A.
The ports belong to an active system and are denying requests B.
The ports are associated with deprecated services C.
The ports do not belong to a live system D.
The ports replied with a SYN/ACK response.
B.
A network administrator wishes to ensure there are no unnecessary open communication paths into a server.
Using a port scanner, the administrator finds that ports are reported as closed.
Which of the following BEST explains this response?
A.
The ports belong to an active system and are denying requests
B.
The ports are associated with deprecated services
C.
The ports do not belong to a live system
D.
The ports replied with a SYN/ACK response.
B.
When a network administrator runs a port scanner against a server, the scanner sends packets to various ports on the server to determine which ports are open and which are closed. If a port scanner reports that ports are closed, it means that the scanner was able to establish a connection to the port, but did not receive any response from the server.
Based on the given options, the BEST explanation for this response would be B, "The ports are associated with deprecated services." This means that the ports being scanned are associated with services that are no longer in use or have been replaced with newer versions or technologies. As a result, these services are not actively listening for incoming connections, which is why the ports are reported as closed.
Option A, "The ports belong to an active system and are denying requests," is not a correct explanation because if the ports were actively denying requests, they would be reported as filtered, not closed.
Option C, "The ports do not belong to a live system," is not a correct explanation either, because if the ports did not belong to a live system, they would not be reported as closed. Rather, they would be reported as either filtered or unresponsive.
Option D, "The ports replied with a SYN/ACK response," is not a correct explanation because a SYN/ACK response indicates that the port is open and actively listening for incoming connections. If a port scanner reported a SYN/ACK response, it would mean that the port is open, not closed.