An Application of SMC to continuous validation of heterogeneous systems

This paper considers the rigorous design of Systems of Systems (SoS), i.e. systems composed of a set of heterogeneous components whose number evolves with time. Such components cooperate to accomplish functions that they could not achieve in isolation. Examples of SoS include smart cities or airport management system. The dynamical evolution of SoS behavior and architecture makes it impossible to design an appropriate solution beforehand. Consequently, existing approaches build on an iterative process that takes SoS evolution into account. A key challenge in this process is the ability to reason about and analyze a given view of the SoS (on a fixed number of SoS constituents) with respect to a set of goals, and use the results to eventually predict the evolution of the SoS. To address this challenge, we rely on a scalable formal verification technique known as Statistical Model Checking (SMC). SMC quantifies how close the current view is from achieving a given mission. We integrate SMC with existing industrial practice, by addressing both methodological and technological issues. Our contribution is: (1) a methodology for validation of SoS formal requirements; (2) a formal specification language able to express complex SoS requirements; (3) the adoption of current industry standards for simulation and heterogeneous systems integration ; (4) a robust SMC tool-chain integrated with system design tools used in practice. We illustrate the application of our SMC tool-chain and the obtained results on a case study.