SHARCS: refinement-centric hazard analysis of requirements for critical systems

The current state of art lacks a methodical, rigorous and scalable single approach to analysis of safety and security requirements.We present SHARCS (Systematic Hierarchical Analysis of Requirements for Critical Systems), addressing this gap by adopting an abstraction-based incremental approach to hazard analysis.SHARCS combines STPA-style control action analysis with Event-B formal modeling and refinement to analyze safety and security of cyber-physical systems by flowing down system-level requirements to component-level requirements.This paper summarizes our recent journal publication [6] with emphasis on two key contributions: (1) a systematic three-phase workflow (system level, component level, consolidation) that guides the incremental development process; (2) control abstraction diagrams, a novel visual notation for modeling control structures at different abstraction levels before concrete design.We demonstrate SHARCS on the Tokeneer secure enclave system, showing how these contributions enable scalable hierarchical decomposition with rigorous traceability.