Modal Open Petri Nets

Abstract

Open nets have an interface of input and output places for modelling asynchronous communication; these places serve as channels when open nets are composed. We study a variant that inherits modalities from Larsen’s modal transition systems. Instantiating a framework for open nets we have developed in the past, we present a refinement preorder in the spirit of modal refinement. The preorder supports modular reasoning since it is a precongruence, and we justify it by a coarsest-precongruence result. We compare our approach to the one of Haddad et al., which considers a restricted class of nets and a stricter refinement. Our studies are conducted in an extended class of nets, which additionally have transition labels for synchronous communication.