Formalization and model checking of software architectural style

Formal analysis is required to check the behavior of the system before implementation of any safety critical system. As the complexity of software increases, the need for reasoning about correct behavior becomes more prominent. Algorithmic analysis of different programs is usually carried out in order to prove their properties of execution. Application of formal method is being considered necessary for modeling, verification, and development of any software or hardware systems. In the formal verification of behavioral model, an attempt has been made to formally describe a real-time system e.g., use of Automated Teller Machine (ATM) in Banks. In this thesis, formal models of ATM system are described using state-based languages such as, Z, B, and Alloy as well as event-based language such as, Monterey Phoenix. Model checking is being carried out by automated tools, viz. Z/EVES, Atelier B, and Alloy Analyzer for Z, B, and Alloy specifications respectively. Furthermore, a comparative analysis of different characteristics shown by varied formal approaches has been presented in this thesis. Software architecture plays an important role in the high level design of a system in terms of components, connectors, and configurations. The main building block of software architecture is an architectural style that provides domain specific design semantics. In the analysis of complex architectural style, an attempt has been made in our work to formalize one complex style e.g., C2 (component and connector) using formal specification language Alloy. For consistency checking of modeling notations, the model checker tool e.g., Alloy Analyzer is used. Alloy Analyzer automatically checks properties such as,compatibility between components and connectors, satisfiability of predicates over the architectural structure, and consistency of an architectural style. For modeling and verification of C2 architectural style, one case study on Cruise Control System has been considered. At the end of this study, performance evaluation of different SAT solvers associated with Alloy Analyzer has been performed in order to assess the quality