What network security concept requires multiple layers of security controls to be placed throughout an IT infrastructure, which improves the security posture of an organization to defend against malic

A Host-Based Intrusion Detection System monitors activity on a single host, representing only one layer of security, not a multi-layer strategy.

Security through obscurity relies on hiding system details to deter attackers rather than implementing substantive layered controls, and is not considered a robust security strategy.

Defense in depth is the formal security principle that mandates placing multiple overlapping security controls - such as firewalls, IDS, access controls, and encryption - at different layers of an IT infrastructure. The layered approach ensures no single point of failure can compromise the entire system. This directly matches the question's description of multiple layers improving an organization's security posture.

A Network-Based Intrusion Detection System monitors network traffic at one point in the infrastructure, which is a single control, not a multi-layered defense approach.