Which technology allows a firewall to block traffic from a known bad location?

Which technology allows a firewall to block traffic from a known bad location?

• A. NAT
• B. Packet Filtering
• C. ACLs
• D. Stateful Inspection

Answer: (B)

Blocking traffic from a known bad location is accomplished by examining each packet’s header and applying a rule that drops packets coming from that source IP. This per-packet decision-making is the essence of packet filtering. It directly uses the source address to determine whether to let the packet through or block it, which is exactly what you need when you’ve identified a bad location. NAT changes addresses and is not about preventing traffic from a specific source. Stateful inspection focuses on whether packets belong to an existing, valid connection rather than simply filtering by origin. ACLs define the rules used by the filtering process, but the underlying capability to block by source IP is packet filtering—the core mechanism that enforces such blocks.

Blocking traffic from a known bad location is accomplished by examining each packet’s header and applying a rule that drops packets coming from that source IP. This per-packet decision-making is the essence of packet filtering. It directly uses the source address to determine whether to let the packet through or block it, which is exactly what you need when you’ve identified a bad location.

NAT changes addresses and is not about preventing traffic from a specific source. Stateful inspection focuses on whether packets belong to an existing, valid connection rather than simply filtering by origin. ACLs define the rules used by the filtering process, but the underlying capability to block by source IP is packet filtering—the core mechanism that enforces such blocks.