Dependability analysis of safety critical systems: Issues and challenges

Safety critical systems progressively used in domains such as nuclear power, transport, medical and information systems are often concerned with a formal process of dependability certification. The intent of dependability process is to ensure that these systems will deliver the expected services to its users. In order to ensure the dependability of large safety-critical systems, the software engineer or security professional needs a thorough knowledge of the process of dependability analysis. In the past several decades, a significant amount of attention has been devoted to the dependability assessment of safety-critical control systems from some perspectives such as reliability, availability, safety, and security. However, for analysis of the critical systems, there is no any universal accepted rigorous dependability analysis process, which helps to choose the metrics, techniques and methodologies for the dependability evaluation of such critical systems. This paper provides a comprehensive detailed literature survey in order to investigate different metrics, threats, means, techniques and methodologies to ensure the dependability of computer-based critical systems. The limitations of these elements are also analyzed with respect to their applicability in SC systems. In addition to this, highlighted various issues (gap), challenges and needs in the context of such systems. The direction for future research is suggested to extend the future scope of research. The purpose of this paper is to interpret a rigorous review concept, of relevance across a wide range of affairs. Therefore, this work helps to the academicians, researchers, and practitioners to put this into practice, analyze the shortcomings of existing research and identifying the open areas that are important for the related community.