What is Assurance Target

Security assurance is the confidence that a system meets its security requirements and is resilient against security vulnerabilities and failures. Existing approaches can be characterized as (1) qualitative in nature, (2) tend to achieve their goals manually to a large extent, (3) very costly, (4) development-process oriented, and finally, (3) treat all security requirements within one domain equally for all applications regardless of the context. In this chapter, the authors propose a security assurance framework and its assurance evaluation process. The framework and process depend on a quantitative security assurance metrics that were developed too. The proposed metric considers both the security requirements and vulnerability. Weight has been introduced to the security requirement metric to measure the importance of security requirements that need to be fulfilled. The framework with the proposed quantitative assurance metrics are evaluated and validated using two field case studies related to two operational REST APIs that belong to and are used by Statistics Norway.