What is the term for strategies that include multiple layers of defense in a security system?

The term that refers to strategies involving multiple layers of defense in a security system is "Defense in Depth." This approach emphasizes the importance of implementing a variety of security measures at different layers, ensuring that if one layer is breached, there are additional layers of security that can provide protection. This concept is vital in creating a more resilient security posture, as it reduces the likelihood of a successful attack by making it more challenging for malicious actors to penetrate every layer of defense.

Defense in depth typically includes a combination of physical security controls, technical controls like firewalls and intrusion detection systems, and administrative controls such as policies and training. By integrating these various defenses, organizations can enhance their overall security effectiveness and mitigate risks more comprehensively.

In contrast, while "Layered Security" may sound similar, it doesn't specifically denote the comprehensive and systematic approach implied by Defense in Depth. "Multi-factor Protection" usually refers to authentication mechanisms requiring more than one form of verification, and "Robust Defense" is a broader term that could refer to strong defenses but does not specifically capture the layered methodology inherent in Defense in Depth.