iSACA Cybersecurity Fundamentals Certification Practice Exam

The primary function of an Intrusion Detection System (IDS) is to monitor network usage for anomalies that may indicate unauthorized access or malicious activities. IDS analyzes traffic patterns and can detect deviations from established baseline behaviors, signaling potential security incidents. By employing various techniques such as signature-based detection and anomaly-based detection, an IDS can identify suspicious activities in real-time, alerting administrators to threats before they can manifest into more significant breaches.

Monitoring network traffic and usage is crucial for maintaining security and integrity within an organization's systems. An IDS plays a vital role in a multi-layered security approach, enabling quick responses to potential threats, which enhances the overall cybersecurity posture.

Other options present different security functions that do not align with the primary goal of an IDS. Preventing unauthorized access to physical areas pertains to physical security measures rather than network monitoring. Providing antivirus protection focuses on detecting and removing malicious software, and performing regular hardware checks relates to equipment maintenance. None of these choices capture the essence of what an IDS is designed to do, which is strictly to monitor and analyze for signs of intrusion or irregular network behaviors.