Generating BDDs for symbolic model checking in CCS

Summary Finite transition systems can easily be represented by binary decision diagrams (BDDs) through the characteristic function of the transition relation. Burch et al. have shown how model checking of a powerful version of the -calculus can be performed on such BDDs. In this paper we show how a BDD can be generated from elementary finite transition systems given as BDDs by applying the CCS operations of parallel composition, restriction, and relabelling. The resulting BDDs only grow linearly in the number of parallel components. This way bisimilarity checking can be performed for processes out of the reach of conventional process algebra tools. Reinhard Enders graduated from the Technical University in Munich with a Diploma in mathematics and computer science in 1978. From 1977 to 1984 he was employed by Siemens, working in computer linguistics and expert systems. From 1984 to 1988 he worked at ECRC on Prolog extensions. In Autmn 1988 he joined Siemens and is developping the constraint extension of a new Prolog product. Thomas Filkorn received the computer science degree and the Ph.D. degree, both from the Technical University of Munich. Since 1992 he works at Siemens' Corporate Research and Development on symbolic algorithms and methods for the verification of finite state systems. Dirk Taubner received his Ph.D. in informatics at the Technical University of Munich in 1988. He investigated which sublanguages of process algebra could be represented finitely by automata and Petri nets. From 1989 through 91 he worked at Siemens' Corporate Research and Development where he led a project on computer-aided verification of parallel processes. This paper presents part of the work of that project. Currently he works on commercial software engineering for a software consulting company.