Modular Architectural Representation and Analysis of Fault Propagation and Transformation

This paper describes a modular representation and compositional analysis of a system's hardware and software components, called Fault Propagation and Transformation Calculus (FPTC). We show, given an architectural description of how components are combined into a whole system, together with an FPTC expression of each component's failure behaviour, how the failure properties of the whole system can be computed automatically from the individual FPTC expressions. From a safety point of view, this provides some idea of robustness: the system's capability to withstand certain types of failures in individual components. It also provides a way to understand how and where to develop fault accommodation within an architecture.