Which statement best describes the difference between Network-Based IDS and Host-Based IDS?

Which statement best describes the difference between Network-Based IDS and Host-Based IDS?

• A. NIDS monitors a single host, HIDS monitors network traffic
• B. HIDS monitors a single host, NIDS monitors network traffic
• C. NIDS uses anomaly-based detection, HIDS uses signature-based detection
• D. HIDS is only used for file systems

Answer: (B)

The main idea is where the monitoring happens and what each system is watching. A host-based IDS focuses on a single machine, gathering data from that host—such as logs, file integrity, process activity, and user authentication events. A network-based IDS, on the other hand, analyzes traffic across the network, typically at segment boundaries or chokepoints, looking for patterns or signatures in packets and flows that indicate intrusions. This distinction lines up with the statement that a HIDS monitors a single host while a NIDS monitors network traffic. In practice, tools like OSSEC or Tripwire illustrate host-based monitoring, while Snort or Suricata operate at the network level. Many environments employ both to achieve comprehensive coverage because attackers can exploit both host-specific and network-wide signals. The other ideas aren’t the defining difference: both types can use either anomaly-based or signature-based detection, and host-based systems monitor more than just file systems—including logs and configuration changes.

The main idea is where the monitoring happens and what each system is watching. A host-based IDS focuses on a single machine, gathering data from that host—such as logs, file integrity, process activity, and user authentication events. A network-based IDS, on the other hand, analyzes traffic across the network, typically at segment boundaries or chokepoints, looking for patterns or signatures in packets and flows that indicate intrusions. This distinction lines up with the statement that a HIDS monitors a single host while a NIDS monitors network traffic.

In practice, tools like OSSEC or Tripwire illustrate host-based monitoring, while Snort or Suricata operate at the network level. Many environments employ both to achieve comprehensive coverage because attackers can exploit both host-specific and network-wide signals. The other ideas aren’t the defining difference: both types can use either anomaly-based or signature-based detection, and host-based systems monitor more than just file systems—including logs and configuration changes.