An integrated and compositional approach to design validation of embedded dependable systems

Complex systems require the use of an inte-grated and best-balanced set of components. The integration and the balanced set are crucial issues, which require some sort of verifiable compositionality property of components that contribute structurally, functionally, non functionally and interactionally to the total quality of the system design. This is even more important when dealing with highly dependable systems. The concept of verifiable compositionality is much more demanding than the usual approach based on composition of building blocks. It implies the preservation of properties and the ability of verifying them. Economic reasons push towards the use of COTS (Commercial Off the Shelf) and towards the re-use of available components, this trend poses new problems. Integration, compositionality and re-use appear to be the very challenging issues in the validation (of both design and implementation) of complex systems, in particular of dependable ones used for controlling critical applications. They require a special effort towards the emergence of a new discipline - System Engineering - which will encompass and integrate the current design disciplines. This paper aims at a discussion in the direction of identifying possible advanced approaches to the validation of dependable systems.