What is a host-based intrusion detection system designed to monitor?

A host-based intrusion detection system (HIDS) is specifically designed to monitor the activities and behavior of a single computer system. It operates by analyzing the operating system, application logs, file system integrity, and the overall behavior of processes on that particular host. The main objective of a HIDS is to identify patterns or anomalies that could indicate potential threats or malicious activities within that specific environment.

By focusing on a single machine, a HIDS can provide detailed insights into local activities and changes — such as file modifications, unauthorized access attempts, and unusual process behaviors. This granularity allows system administrators to detect security incidents at the host level, making it an essential tool in a layered security approach.

In contrast, other systems designed to monitor network activity or multiple hosts, such as network-based intrusion detection systems (NIDS), are distinct entities that serve different purposes. For example, a network-based system would analyze traffic across the entire network rather than focusing on the individual behavior of a single host. Thus, the emphasis on monitoring a singular system is what makes the chosen answer the most accurate description of a host-based intrusion detection system.