GSEC Network Security Devices Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  The IPS inspection engine is sized and tuned so that it can process the full 10 Gbps line rate with expected burst traffic.

  Why this is correct

  An inline IPS must keep up with line rate; otherwise it will drop legitimate packets or introduce unacceptable latency. Sizing and tuning the inspection engine for the full 10 Gbps plus expected bursts ensures the device does not become a performance bottleneck or a de facto denial of service. This directly supports the goal of maintaining availability while enforcing prevention. It is a fundamental capacity planning requirement for inline IPS on critical high-speed links.

• ✗

  The IPS is configured to drop all traffic that it cannot inspect, including encrypted sessions it cannot decrypt.

  Why it's wrong here

  Dropping all uninspectable traffic, including encrypted sessions, would cause severe availability problems and block legitimate business communication. The goal is to minimize single-point-of-failure risk and still block malicious traffic, not to enforce a fail-closed policy on all uninspected flows. Such a configuration would likely create outages and is not a recommended design characteristic for an inline IPS on a critical link. It confuses strict enforcement with availability preservation.

• ✗

  The IPS is managed out-of-band on a separate management VLAN with restricted access.

  Why it's wrong here

  Out-of-band management on a restricted VLAN is a good security practice, but it does not address the single-point-of-failure or line-rate requirements for inline traffic. It improves management security and availability of the management plane, yet it does not ensure data-plane continuity or inspection capacity. Because the question asks for design characteristics that minimize single-point-of-failure risk while still blocking traffic, this option is not one of the two required characteristics.

• ✓

  The IPS supports a hardware bypass or fail-open mechanism that forwards traffic if the device loses power or fails.

  Why this is correct

  Hardware bypass or fail-open ensures that if the IPS fails or loses power, traffic continues to flow, preventing a complete outage. This directly addresses the single-point-of-failure concern while allowing the IPS to block malicious traffic during normal operation. It is a standard requirement for inline IPS on critical links because availability must be preserved even when the security control is unavailable. Without it, an IPS failure could halt all business traffic.

• ✗

  The IPS is deployed in passive mode with a span port so that it can alert without affecting traffic flow.

  Why it's wrong here

  Passive mode with a span port avoids becoming a single point of failure, but it also cannot block malicious traffic inline. The scenario requires both minimizing single-point-of-failure risk and still blocking malicious traffic. Passive deployment removes the inline enforcement capability, so it does not satisfy the blocking requirement. It may be useful for monitoring, but it is not a valid inline IPS design characteristic for this requirement.