Condensed Storage of Multi-Set Sequences

Tools for state space exploration, or reachability analysers, work by incrementally constructing a set of reachable states. The applicability of these tools is limited by the vast state space of real systems. One way to attack this problem are different reduction methods— another approach is to come up with techniques for representing the set of reachable states in a compact way. The state—or marking—of a high-level Petri net can be viewed as a sequence of finite multi-sets. A method for encoding markings containing structured values is described, and a comparison to an earlier implementation is presented.