The University of SydneyPage 35Principles 3: Defense in Depth as Strategy–Defense in depth–Involves implemented security in overlapping layers that provide the three elements needed to secure assets: prevention, detection, and response–The weaknesses of one security layer are offset by the strengths of two or more layers
For example, a typical Internet-attached network designed with security in mind includes routers, firewalls, and intrusion detection systems (IDS) to protect the network from would-be intruders; employs traffic analyzers and real-time human monitors who watch for anomalies as the network is being used to detect any breach in the layers of protection; and relies on automated mechanisms to turn off access or remove the system from the network in response to the detection of an intruder.