Which term describes any device that controls or filters traffic going in or out of the network?

Which term describes any device that controls or filters traffic going in or out of the network?

• A. Router
• B. Firewall
• C. IDS/IPS
• D. Switch

Answer: (B)

A firewall is the device that controls or filters traffic going in or out of a network. It sits at the network boundary and enforces security policies, deciding which packets or flows are allowed and which are blocked based on rules about IP addresses, ports, protocols, and sometimes application data. This gatekeeping function is what differentiates a firewall from other devices. Routers focus on finding the best path for data to travel through a network, not on filtering traffic by policy. Switches move frames within a local network, primarily by MAC address. IDS/IPS systems monitor for signs of intrusion and can block traffic when configured, but their main role is detection and response, not universal traffic control at the network boundary.

A firewall is the device that controls or filters traffic going in or out of a network. It sits at the network boundary and enforces security policies, deciding which packets or flows are allowed and which are blocked based on rules about IP addresses, ports, protocols, and sometimes application data. This gatekeeping function is what differentiates a firewall from other devices.

Routers focus on finding the best path for data to travel through a network, not on filtering traffic by policy. Switches move frames within a local network, primarily by MAC address. IDS/IPS systems monitor for signs of intrusion and can block traffic when configured, but their main role is detection and response, not universal traffic control at the network boundary.