Interface Mode for Passive Traffic Reception

B.

With Cisco FTD (Firepower Threat Defense) software, the interface mode that must be configured to passively receive traffic that passes through the appliance is the "inline tap" mode.

In inline tap mode, the Cisco FTD appliance is connected to a network segment in a way that allows it to monitor traffic flowing through that segment without actively participating in the network traffic. This means that the Cisco FTD appliance can inspect the traffic passing through it and detect any potential security threats, without disrupting or affecting the flow of the traffic.

In contrast, the other interface modes - inline set, passive, and routed - do not provide the same level of visibility and control over network traffic. For example:

• Inline set mode involves the Cisco FTD appliance actively participating in the network traffic and making decisions on how to handle each packet based on configured policies. This mode is useful for enforcing security policies and blocking malicious traffic, but it may also introduce latency and disruption to the network traffic.

• Passive mode simply copies the network traffic to the Cisco FTD appliance, without actually processing or modifying the traffic. This mode is useful for monitoring network traffic without introducing any disruption or delay, but it may not be able to detect certain types of threats that require active inspection.

• Routed mode involves the Cisco FTD appliance acting as a traditional router, forwarding packets between different network segments based on configured routing tables. This mode is useful for segmenting the network and controlling traffic flow, but it may not provide the same level of visibility and control over network traffic as inline tap mode.

Overall, the choice of interface mode depends on the specific security requirements and network architecture of the organization, and should be carefully evaluated before deployment.