Summary: Using Forward Reachability Analysis for Verification of
Timed Petri Nets #
Parosh Aziz Abdulla, Johann Deneux, Pritha Mahata, and Aletta Nyl’en
Uppsala University, Sweden
{parosh,johannd,pritha,aletta}@it.uu.se
Abstract. We consider verification of safety properties for concurrent real­timed
systems modelled as timed Petri nets, by performing symbolic forward reachability
analysis. We introduce a formalism, called region generators for representing sets of
markings of timed Petri nets. Region generators characterize downward closed sets
of regions, and provide exact abstractions of sets of reachable states with respect
to safety properties. We show that the standard operations needed for performing
symbolic reachability analysis are computable for region generators. Since forward
reachability analysis is necessarily incomplete, we introduce an acceleration tech­
nique to make the procedure terminate more often on practical examples. We have
implemented a prototype for analyzing timed Petri nets and used it to verify a pa­
rameterized version of Fischer's protocol, Lynch and Shavit's mutual exclusion pro­
tocol and a producer­consumer protocol. We also used the tool to extract finite­state
abstractions of these protocols.
Keywords: Timed Petri Nets, Model Checking, Reachability Analysis, Downward
Closed Languages

Source: Abdulla, Parosh Aziz - Department of Information Technology, Uppsala Universitet

Collections: Computer Technologies and Information Sciences