Definition
The Secure Software Development Lifecycle (SSDLC) is a process model that integrates security requirements into every stage of software design, development, testing, deployment and maintenance.
Human Explanation
Security is considered throughout software development rather than only shortly before deployment.
Why it Matters
Finding security problems earlier reduces remediation cost and the Risk of Vulnerabilities reaching production.
Conceptual Boundary
SSDLC does not replace the standard software development lifecycle. It extends that lifecycle with security activities.
Practical Perspective
The earlier security is included in software development, the easier it is to maintain an appropriate level of protection.