Which statement about Intrusion Detection Systems (IDS) is correct?

The correct statement about Intrusion Detection Systems (IDS) is that they are not effective in preventing intrusion. IDS are designed primarily to monitor network traffic and system activities for suspicious behavior or policy violations. Their role is to detect and alert security personnel about potential intrusions, enabling them to take appropriate action.

While IDS can provide valuable insights and alerts regarding unauthorized access or anomalous activity, they do not actively block or prevent intrusions themselves. That function is typically handled by Intrusion Prevention Systems (IPS), which can take action to stop intrusions as they occur. Therefore, understanding that IDS focuses on detection rather than prevention is essential for grasping the role these systems play in an overall security strategy.

The other options misrepresent the capabilities of an IDS. Some suggest that IDS can prevent all types of intrusions or operate independently without monitoring, which is not aligned with how these systems function in a security environment.