Priorities for Modeling and Verifying Distributed Systems

This paper illustrates the use of priorities in process algebras by a real-world example dealing with the design of a safety-critical network which is part of a railway signaling system. Priorities in process algebras support an intuitive modeling of distributed systems since undesired interleavings can be suppressed. This fact also leads to a substantial reduction of the sizes of models. Wehave implemented a CCS-based process algebra with priorities as a new front-end for the NCSU Concurrency Workbench, and we use model checking for verifying properties of the signaling system. 1 Introduction Process algebras, e.g. CCS #13#, provide a formal framework for modeling and verifying distributed systems. In the past decade, a number of automatic veri#cation tools for #nite state systems expressed in process algebras have been developed #10#, and their utility has been demonstrated by several case studies #1, 7#. Most of these case studies are based on process algebras that provide ..