A modular risk concept for complex systems

This paper motivates the views that for complex systems, risk should be controlled by enforcing constraints in a modular way at different system levels, that the constraints can be expressed as assurance contracts and that acceptable risk mitigation can be demonstrated in assurance case modules. This short paper explains how already existing methodologies can be combined to create a concept for modular risk assessment. The main novelty is the use of so-called contract-based design (CBD) contracts and refinements as risk constraints. This idea is presented here with the objective of receiving feedback from industry and academia.