Which statement best describes stateful packet inspection firewalls?

• A. Always do application content filtering
• B. Have the slow speed of relay operation
• C. Both A and B
• D. Neither A nor B

Answer: (D)

Stateful packet inspection focuses on tracking the state of active connections and making filtering decisions based on that context, not on inspecting every byte of application data. This means it’s not inherently about applying application-layer content filtering; that kind of deep, protocol-specific content scrutiny is typically handled by application-layer firewalls or deep packet inspection at the app level, not by basic stateful filtering.

Speed and performance aren’t dictated by the concept itself either. A stateful firewall can operate very quickly when hardware acceleration or optimized software paths are used, though there may be some overhead compared to purely stateless filtering. The key point is that being “slow” isn’t a defining trait of stateful packet inspection.

So the description that fits best is that stateful packet inspection does not inherently perform application content filtering and does not have to be slow by default; the two statements given don’t accurately describe its core behavior.