Applications of hierarchical reasoning in the verification of complex systems

In this paper we show how hierarchical reasoning can be used to verify properties of complex systems. Chains of local theory extensions are used to model a case study taken from the European Train Control System (ETCS) standard, but considerably simplified. We show how testing invariants and bounded model checking (for safety properties expressed by universally quantified formulae, depending on certain parameters of the systems) can automatically be reduced to checking satisfiability of ground formulae over a base theory