A bottom-up algorithm for state-space size estimation of Petri nets

A bottom-up state-space size estimation algorithm for Petri nets (PNs) is described. The algorithm permits fairly arbitrary subnets and interconnections. State counting (SC) functions are associated with subnets and manipulated by the interconnections. As illustrated by a flexible manufacturing system (FMS) example, if no approximations of the subnets are needed, the state-space size estimation is exact. Other benefits include simple tabular representation of SC functions, and the ability to interject hand-computed results. While all conceivable PNs cannot be handled by any bottom-up method, the interconnection can be extended to permit analysis on a larger class of systems