Parametric Model Checking

T. Hune, J.M.T. Romijn, M.I.A. Stoelinga and F.W. Vaandrager. Linear parametric model checking of timed automata. Journal of Logic and Algebraic Programming 52-53:183--220, 2002.


We present an extension of the model checker Uppaal, capable of synthesizing linear parameter constraints for the correctness of parametric timed automata. A symbolic representation of the (parametric) state space in terms of parametric difference bound matrices is shown to be correct. A second contribution of this paper is the identification of a subclass of parametric timed automata (L/U automata), for which the emptiness problem is decidable, contrary to the full class where it is known to be undecidable. Also, we present a number of lemmas that reduce the verification effort for L/U automata in certain cases. We illustrate our approach by deriving linear parameter constraints for a number of well-known case studies from the literature (exhibiting a flaw in a published paper).