Reusing dynamic communication protocols in self-adaptive embedded component architectures

Component based software engineering aims at re-using components in other systems. This requires a verification whether the component can safely interact with its communication partners in a new environment. Such verification is mandatory in case of safety-critical real-time systems where the communication is characterized by a varying number of components instances all being of the same type. Reuse can be facilitated by separating abstract communication protocol definitions and concrete component implementations. In contrast to standard refinement definitions for real-time systems, our definition explicitly takes varying numbers of communication partners into account. Additionally, we relax the strict conditions of a bisimulation to ease reuse of components. Along with our refinement definition, we provide a formal verification procedure to check for correct refinements which preserves properties verified for the abstract protocol definition. We evaluated our approach using a self-adaptive real-time system from the domain of autonomous train systems. The evaluation results show that checking for correct refinements is more efficient than re-verifying the desired properties on the refined component.