Advanced Ramsey-based Büchi Automata Inclusion Testing

zpráva odborná

angličtina

Checking language inclusion between two nondeterministic Büchi automata A and B is computationally hard (PSPACE-complete). However, several approaches which are efficient in many practical cases have been proposed. We build on one of these, which is known as the Ramsey-based approach. It has recently been shown that the basic Ramsey-based approach can be drastically optimized by using powerful subsumption techniques, which allow one to prune the search-space when looking for counterexamples to inclusion. While previous works only used subsumption based on set inclusion or forward simulation on A and B, we propose the following new techniques: (1) A larger subsumption relation based on a combination of backward and forward simulations on A and B. (2) A method to additionally use forward simulation between A and B. (3) Abstraction techniques that can speed up the computation and lead to early detection of counterexamples. The new algorithm was implemented and tested on automata derived from real-world model checking benchmarks, and on the Tabakov-Vardi random model, thus showing the usefulness of the proposed techniques.

Büchi automata, inclusion checking, Ramsey theorem, simulation relations

ABDULLA, P.; CHEN, Y.; CLEMENTE, L.; HOLÍK, L.; HONG, C.; MAYR, R.; VOJNAR, T.

19. 6. 2011

Faculty of Information Technology BUT

FIT-TR-2011-03, Brno

45

http://www.fit.vutbr.cz/~vojnar/Publications/fit-tr-2011-03.pdf