Complexity studies for safe and fan-bounded elementary hornets

HORNETS are Petri nets that have nets as tokens. There are an algebraic extension of elementary object nets (EOS) with the possibility to mofify the structure of the net-tokens. In previous contributions we investigated elementary HORNETS as well as their subclass of safe elementary HORNETS. We showed that the reachability problem for safe elementary HORNETS requires at least exponential space. We have also showed that exponential space is sufficient. This shows that safe elementary HORNETS are much more complicated than safe elementary object nets (safe EOS), where reachability is known to be PSPACE-complete. In this contribution we study structural restrictions of elementary HORNETS that have a better complexity: fan-bounded HORNETS. It turns out that reachability is again in PSPACE for this class of HORNETS.