Characterizing Software Architectural Metrics for Continuous Compliance in the Automotive Domain

The software of critical systems, such as automotive, is increasingly required to change and evolve after production. In the automotive domain, this is a consequence of self-driving and connected cars, which continuously collect data from the field that is then exploited to produce safer and more advanced and reliable versions of the used algorithms or AI modules. Consequently, there exists a need for techniques and tools to facilitate incremental and Continuous Compliance with safety and security standards. This paper focuses on software architectural metrics that can be used for Continuous Compliance in the automotive domain. Our initial stride involved a literature review to find metrics capable of assessing software architectures. Subsequently, in collaboration with architecture, safety, and security experts in the automotive domain, we proposed a framework defining the characteristics these metrics must possess for continuous evaluation of software architectural compliance. The framework was used to characterize 48 metrics gathered from the literature review and to associate them with a score expressing their suitability to be used in software architecture Continuous Compliance processes.