A concurrency characteristic in Petri net unfolding

Unfolding, originally introduced by McMillan (1995), is gaining ground as a partial-order based method for the verification of concurrent systems without state-space explosion. However, it can be exposed to redundancy, which may increase its size exponentially. So far, there have been trials to reduce such redundancy resulting from conflicts by improving McMillan´s cut-off criterion. In this paper, we show that concurrency is also another cause of redundancy in unfolding, and we present an algorithm to reduce such redundancy in live, bounded and reversible Petri nets, which is independent of any cut-off algorithm