Where can an IDS be deployed?

Where can an IDS be deployed?

• A. Always inside the firewall
• B. Only outside the firewall
• C. May be placed either outside or inside the firewall
• D. Only inside the DMZ

Answer: (C)

An IDS is a sensor that monitors network traffic to detect suspicious activity, so its placement depends on what you want to monitor and where threats are likely to come from. You can put it at the network edge to see inbound attempts before they hit the firewall, or inside the network to inspect traffic after it has passed the firewall and to monitor internal communications. Because visibility from different viewpoints improves detection, there isn’t a single fixed location; it can be placed outside or inside the firewall depending on the monitoring goals. Some designs also use IDS in the DMZ, but the core idea is flexibility in placement to achieve the desired visibility.

An IDS is a sensor that monitors network traffic to detect suspicious activity, so its placement depends on what you want to monitor and where threats are likely to come from. You can put it at the network edge to see inbound attempts before they hit the firewall, or inside the network to inspect traffic after it has passed the firewall and to monitor internal communications. Because visibility from different viewpoints improves detection, there isn’t a single fixed location; it can be placed outside or inside the firewall depending on the monitoring goals. Some designs also use IDS in the DMZ, but the core idea is flexibility in placement to achieve the desired visibility.