Verification of Timed Automata Using Rewrite Rules and Strategies

ELAN is a powerful language and environment for specifying and prototyping deduction systems in a language based on rewrite rules controlled by strategies. Timed automata is a class of continuous real-time models of reactive systems for which efficient model-checking algorithms have been devised. In this paper, we show that these algorithms can very easily be prototyped in the ELAN system. This paper argues through this example that rewriting based systems relying on rules and strategies are a good framework to prototype, study and test rather efficiently symbolic model-checking algorithms, i.e. algorithms which involve combination of graph exploration rules, deduction rules, constraint solving techniques and decision procedures

Modeling of Complex Systems II: A minimalist and unified semantics for heterogeneous integrated systems

International audienceThe purpose of this paper is to contribute to a unified formal framework for complex systems modeling. To this aim, we define a unified semantics for systems including integration operators. We consider complex systems as functional blackboxes (with internal states), whose structure and behaviors can be constructed through a recursive integration of heterogeneous components. We first introduce formal definitions of time (allowing to deal uniformly with both continuous and discrete times) and data (allowing to handle heterogeneous data), and introduce a generic synchronization mechanism for dataflows. We then define a system as a mathematical object characterized by coupled functional and states behaviors. This definition is expressive enough to capture the functional behavior of any real system with sequential transitions. We finally provide formal operators for integrating systems and show that they are consistent with the classical definitions of those operators on transfer functions which model real systems

Formal Modeling and Analysis of Leader Election in MANETs

The modeling and analysis of mobile ad hoc networks MANETs pose non-trivial challenges to formal methods. Time, geometry, communication delays and failures, mobility, and uni- and bidirectionality can interact in unforeseen ways that are hard to model and analyze by automatic formal methods. In this work we use rewriting logic and Real-Time Maude to address this challenge. We propose a composable formal framework for MANET protocols and their mobility models that can take into account such complex interactions. We illustrate our framework by analyzing a well-studied leader election protocol for MANETs in the presence of both mobility and uni- and bidirectional links.NSF Grant CNS 13-19109AFOSR Grant FA8750-11-2-0084Ope

Twenty years of rewriting logic

AbstractRewriting logic is a simple computational logic that can naturally express both concurrent computation and logical deduction with great generality. This paper provides a gentle, intuitive introduction to its main ideas, as well as a survey of the work that many researchers have carried out over the last twenty years in advancing: (i) its foundations; (ii) its semantic framework and logical framework uses; (iii) its language implementations and its formal tools; and (iv) its many applications to automated deduction, software and hardware specification and verification, security, real-time and cyber-physical systems, probabilistic systems, bioinformatics and chemical systems