CompTIA Security Plus Mock Test Q132

After a new firewall has been installed, devices cannot obtain a new IP address. Which of the following ports should Matt, the security administrator, open on the firewall?

A. 25
B. 68
C. 80
D. 443

Correct Answer: B
Section: Network Security

Explanation:
The Dynamic Host Configuration Protocol (DHCP) is a standardized network protocol used on Internet Protocol (IP) networks for distributing IP addresses for interfaces and services. DHCP makes use of port 68.

Incorrect Answers:
A: SMTP makes use of port 25.
C: HTTP makes use of port 80.
D: HTTPS makes use of port 443

References:
http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol
http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers