Formal Analysis Approach for Multi-layered System Safety and Security Co-engineering

Abstract

Critical domains (like Cyber-Physical Systems-CPSs) have witnessed increased demand for considering both safety and security concerns during the early phases of the System Engineering (SE) process. Particularly, in the design phase, safety and security requirements should cascade down across different system views till the architectural design. However, such an enrichment process is often complex and lacks guidance to precisely specify the corresponding properties and consistently break down high-level system specifications into intricate architecture for a rigorous analysis. To this end, we propose a formal approach pursuing joint analysis of safety and security objectives, specialize-able across different system views. In particular, the approach strives for a multi-layered system representation, integrating mission, functional and component views, and libraries of pre-defined safety and security properties, instantiate-able at each layer. We rely upon the meta-modeling and formal techniques for the specification, conceptual modeling, formal interpretation, and verification of the system w.r.t. the allocated properties. The overall approach is validated using Rodin as an instance of a formal-based tool for properties' verification.