A System-Level Approach for Model-Based Verification of Distributed Software Systems

A major challenge in design of distributed software systems is predicting and avoiding unexpected behaviors at the run time. Detecting those behaviors after the system is implemented can be very costly and detecting them during design and implementation stages is a cost effective alternative. Therefore, model-based verification at early design stages is an important step in designing distributed systems. Most of the existing verification techniques analyze system behaviors by going from specifications to state machines that model individual components' behaviors. Although those methods are shown to be effective in detecting unexpected behaviors for each component, they fail to detect the unexpected behaviors that occur at the system level. There exist a few ad-hoc methods to combine components' behavior into system level behavior. In this paper, we devise a method that considers interactions among components, and propose an algorithm to combine the behavior models of interacting components. The proposed algorithm can be used to perform automated system-level verification. A case study is developed to validate the efficiency of the proposed algorithm in detecting the implied scenarios for distributed system.