Towards a discipline of system engineering: validation of dependable systems architectures

Computer controlled systems are used in many fields of applications, with different levels of criticality requirements. A common characteristic of such systems is the increasing complexity in intrinsic terms (management of distribution, redundancy, layering of functionalities, etc.) and of the in-the-field operation (interfaces towards the environment, timing constraints, criticality of the controlled applications, etc.). This increasing complexity rarely can be completely mastered and usual design practices often suffer from partial approaches, overlooked details, inadequate modeling, insufficient prototyping, limited design tools or techniques available; not to deal with incorrect or incomplete or not understood user requirements, which are often the cause of the final failure of a design or system