What is the purpose of an Intrusion Detection System (IDS)?

An Intrusion Detection System (IDS) primarily serves to monitor network traffic and identify potential security incidents by analyzing patterns and anomalies. Its main purpose is to detect unauthorized access, policy violations, or other malicious activities, and to log this information for further investigation by security personnel. The system generates alerts when it identifies behaviors that meet predefined threat criteria, allowing security teams to respond accordingly.

While an IDS plays a crucial role in enhancing security by providing visibility into potential threats, it does not prevent attacks in real-time—that function is typically handled by an Intrusion Prevention System (IPS). An IDS also does not actively filter traffic or enforce access controls; instead, it focuses on detection and logging, thus providing valuable insights into network security incidents without taking direct preventive action.