Modeling and specification of discrete event systems using combined process algebra and Petri nets

A modeling framework for general routing and resource booking problems is presented. The task is to specify desired routes for individual objects (products, data packets, vehicles), which are to be served by a number of shared resources (machines, computers, communication links). Based on simple booking models for the resources and routing specifications for the objects, a controller that synchronizes the objects utilization of the available resources is automatically generated. A high level language is presented in order to simplify the specification of desired routes. This modeling language combines Petri nets and process algebra. Process operators are introduced for specification of alternative and synchronization, which are applied in order to model join and split operations. Multiple as well as alternative resources are easily specified utilizing sets of resources. These sets and operators imply a very compact and efficient representation of complex routing specifications. In fact, the representation is suitable for verification and synthesis based on symbolic tools such as binary decision diagrams.