Which is a network security boundary control that monitors and filters traffic?

Which is a network security boundary control that monitors and filters traffic?

• A. Firewall
• B. Antivirus
• C. Password Policy
• D. Encryption

Answer: (A)

A firewall is a network security boundary control that sits at the edge between trusted and untrusted networks. It watches traffic crossing that boundary and applies rules to decide which packets to permit or block, effectively monitoring and filtering traffic to prevent unwanted access. This boundary-focused enforcement is what characterizes a firewall, whether deployed as a network device or a host-based option, and it can perform functions like packet filtering, stateful inspection, and rule-based access control. In contrast, antivirus operates on a host to detect malware, not to govern network traffic at the boundary; password policy governs how credentials are used rather than traffic flow; and encryption protects data but does not by itself decide which traffic to allow or disallow across the network boundary.

A firewall is a network security boundary control that sits at the edge between trusted and untrusted networks. It watches traffic crossing that boundary and applies rules to decide which packets to permit or block, effectively monitoring and filtering traffic to prevent unwanted access. This boundary-focused enforcement is what characterizes a firewall, whether deployed as a network device or a host-based option, and it can perform functions like packet filtering, stateful inspection, and rule-based access control. In contrast, antivirus operates on a host to detect malware, not to govern network traffic at the boundary; password policy governs how credentials are used rather than traffic flow; and encryption protects data but does not by itself decide which traffic to allow or disallow across the network boundary.