CompTIA Network+ N10-006 Q3

Which of the following network devices use ACLs to prevent unauthorized access into company systems?

B. Firewall
C. Content filter
D. Load balancer

Correct Answer: B

Section: Network architecture

A firewall is a system designed to prevent unauthorized access to or from a private network. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. Firewalls use ACLs (access control lists) to determine which traffic is allowed through the firewall. All traffic entering or leaving the intranet passes through the firewall, which examines each message and blocks or allows the message depending on rules specified in the ACL. The rules in the ACL specify which combinations of source IP address, destination address in IP port numbers are allowed.