Dependability Assessment of SOA-based Cyber-Physical Systems with Contracts and Model-Based Fault Injection [article]

Passerone Roberto
In the era of interconnected systems it is becoming more and more important to address issues of scale in system safety and dependability assessment. Concurrency has no longer to be understood only as a concern within individual systems -but rather also and mostly as between them. Yielding the correct deployment of such systems is thus challenging. Besides technical complications also social collaborations between engineering teams intertwine, whereby the need of communicating unambiguously
more » ... r component's potentials and needs is both paramount and difficult to attain. This is a major concern in the development of Cyber-Physical Systems (CPSs), where computation is put at service of the physical world to let constituent embedded components accomplish some given goal. The main objective of this thesis is the development of novel techniques for the dependability analysis of highly distributed systems structured over the concept of Service-Oriented Architecture (SOA), with particular consideration to needs coming from the industry sector. Focusing on component services as the central means at the core of each interaction, our methodology will thus show how existing techniques applicable to plain digital components can be lifted to the broader area of complex Cyber-Physical Systems. We will commit on modeling Cyber-Physical Systems of different sorts, first accounting for their cyber-physical aspects and then considering changes in topology typical of SOA. For this we will stick to the UML language extensions of SoaML and SysML, being them particularly amenable to industry. We will then advocate the intensive use of contracts, already well-established for the design of heterogeneous CPSs, as an indispensable and perfectly tailored concept for services. We will demonstrate how non-functional requirements, such as timing, can be incorporated in the presented framework. At the end of the presentation we will demonstrate how the employment of XSAP, a tool for the safety analysis of state-based systems based on nuXmv, can be adapted to accommodate the dependability analysis of SOA-based Cyber-Physical Systems. To that aim we will show how to model and analyze two specific use case examples inspired by the literature by featuring XSAP in a novel way. We will present the results of the analysis with respect to our findings and conclude with a discussion over the whole methodology and future directions.
doi:10.15168/11572_170973 fatcat:4obvdck4fre7la3low4cxo42pe