Development of the System Assurance Reference Model for Generating Modular Assurance Cases

Andrzej Wardziński; Aleksander Jarzębowicz

doi:10.1109/prdc59308.2023.00022

Development of the System Assurance Reference Model for Generating Modular Assurance Cases

Abstract

Assurance cases are structured arguments used to demonstrate specific system properties such as safety or security. They are used in many industrial sectors including automotive, aviation and medical devices. Larger assurance cases are usually divided into modules to manage the complexity and distribute the work. Each of the modules is developed to address specific goals allocated to the specific objects i.e. components of the system’s architecture. Such goals are applicable for given conditions of use, for instance, operational modes or target environments. It is recommended that the complete context of each of the argument modules, encompassing information about systems/components, goals and conditions of use, is described explicitly to enable efficient management and proper use of each module. This becomes even more important for component-based design, including the use of out-of-context components. In this paper, we describe a concept of a generic System Assurance Reference Model (SARM), which bridges the gap between assurance cases and the related context models. We identify the key factors that condition the high-level assurance case structure, explain how they can drive its decomposition into assurance case modules and outline the process of creating and using context models. We present a prototype solution which implements the SARM model and enables automatic data flow between models and assurance cases.