Guide to Security Needs and Requirements – Making Security a Functional Requirement

The INCOSE Systems Security Working Group completed a 2-year project to create a Guide to Security Needs and Requirements targeting both the systems engineering practitioner and the systems security practitioner to help them collaboratively define security needs and requirements that result in a secure system in operation. Starting with a set of anti-patterns for security requirements, we identified existing tactics that have not produced secure systems in the operational environment. The team then identified an approach to perform needs-oriented, loss-driven, capability-based analysis across the systems engineering activities. The result is a set of need statements capturing the stakeholder expectations concerning security and a set of functional requirements defining what the system must do to address those needs. Defining security as a functional requirement helps us design a system that can prepare for, defend against, and recover from adversity to achieve and sustain mission success.