Ethical Hacking: Techniques, Tools, and Countermeasures, 4th Edition

Intrusion Detection Systems

The defense-in-depth approach depends on having controls at multiple levels. That means that an attacker should encounter multiple controls before reaching any protected resource. Controls in a defense-in-depth strategy should be of different types, such as prevention and detection controls, and should be deployed at different levels in the infrastructure. One of the tools that enables you to detect an attack is an intrusion detection system (IDS). An IDS provides the ability to monitor a network, server, or application and generate an alert when it detects suspicious activity. The essence of intrusion detection is the process of detecting potential misuse or attacks and the ability to respond based on the alert that ...