On Applicability of Formal Methods and Tools to Dependable Services

As a variety of digital services are provided through networks, more and more efforts are made to ensure dependability of software behavior implementing services. Formal methods and tools have been considered as promising means to support dependability in complex software systems during the development. On the other hand, there have been serious doubts on practical applicability of formal methods. This paper overviews the present state of formal methods and discusses their applicability, especially focusing on two representative methods (SPIN and B Method) and their recent industrial applications. This paper also discusses applications of formal methods to dependable networked software. key words: dependability, software engineering, formal methods