Definition(s)
Security Layers of Protection
Also known as concentric “rings of protection,” a concept of providing multiple independent and overlapping layers of protection in depth. For security purposes, this may include various layers of protection such as countersurveillance, counterintelligence, physical security, and cyber security. A second consideration is the balance of the security measures such that equivalent risk exists regardless of the threat’s pathway or method.
Source:API STANDARD 780, Security Risk Assessment Methodology for the Petroleum and Petrochemical Industries, First Edition, May 2013. Global Standards