Component Based Design of Fault Tolerant Devices in Cyber Physical System

The complexity of software in safety critical systems has increased significantly over the last ten years so that how to tackle the complexity and gain high dependable software plays an important roles in ensuring the overall product quality. In this context, component based development (CBD) has been successfully applied to large scale software system in the fields of Software Engineering. Similarly, System Safety Analysis (SSA) has also gained wide used in critical systems in the fields of System Safety Engineering. But they often used their methodology in isolation. Furthermore, shortage of unified formal framework to bridge the gap between the CBD and SSA make it hard to integrate them into a unified rigorous development process for safety critical systems. This paper describes a new approach called Component Fault Tree and Fault Tolerant pattern guided Fault Tolerant Software Architecture (CFT3SA), which bridge the gap between CBD and SSA to realize the seamless integration of CBD and SSA. Furthermore, the formal definitions of Component Fault Tree, Fault tolerant Pattern underpin the systematical verification and validation of fault tolerant systems. A case study from the Odemetry Safe System in the train control domain has been used to valuate the feasibility of the proposed fault tolerant software architectural solution.