IAB201 Lecture Notes - Lecture 11: Petri Net, Bounded Set, Workflow Management System
Document Summary
Process models are often formalised as directed graphs. Idea: rely on structural properties to characterise good models. Implemented, for instance, in the notion of wf-nets (also referred to as structural soundness) A strongly connected directed graph is a directed graph in which it is possible to reach any vertex starting from any other vertex in the graph, by traversing edges in the direction(s) in which they point. If petri net n is a wf-net and we add a transition t* to it which connected terminal place o with initial place i, then the resulting petri net is strongly connected. If this is the case, then every place and every transition of the petri net is on some (directed) path between i and o, therefore petri net n is a wf-net. Structural soundness/correctness is not sufficient for a graph to be fully "correct"!