IDS
An intrusion detection system (IDS) is a system that detects attacks targeting servers, networks, and computers at an early stage. The Intrusion Detection System is often an addition to the firewall. If an attack is detected by the IDS, the system informs the responsible employee(s) about the attack. An attack follows a certain pattern, which the system recognizes. In many cases, the IDS runs as self-running hardware or as software installed on a computer system. The IDS differs from the Intrusion Prevention System (IPS) in that it only has an informative character in the event of an attack, while the IPS also knows how to prevent attacks.