The model of timed I/O automata represents an extension of the model of I/O automata with the aim of reasoning about realtime systems. A number of case studies using timed I/O automata has been carried out, among them a treatment of the so-called Generalized Railroad Crossing (GRC). An already existing formalization of the metatheory of I/O automata within Isabelle/HOLCF allows for fully formal...

In this paper, we propose an abstract procedure which, given a timed automaton, produces a language-equivalent deterministic infinite timed tree. We prove that under a certain boundedness condition, the infinite timed tree can be reduced into a classical deterministic timed automaton. The boundedness condition is satisfied by several subclasses of timed automata, some of them were known to be d...

In this paper, we introduce the model of communicating timed automata (CTA) that extends the classical models of finite-state processes communicating through FIFO perfect channels and timed automata, in the sense that the finite-state processes are replaced by timed automata, and messages inside the perfect channels are equipped with clocks representing their ages. In addition to the standard o...

We provide a unifying view of timed models such as timed automata, probabilistic timed automata, and Markov automata. The timed models and their bisimulation semantics are encoded in the framework of uniform labeled transition systems. In this unifying framework, we show that the timed bisimilarities present in the literature can be reobtained and that a new bisimilarity, of which we exhibit th...

In this paper, we propose an abstract procedure which, given a timed automaton, produces a language-equivalent deterministic infinite timed tree. We prove that under a certain boundedness condition, the infinite timed tree can be reduced into a classical deterministic timed automaton. The boundedness condition is satisfied by several subclasses of timed automata, some of them were known to be d...

Weighted timed automata extend timed automata with cost variables that can be used to model the evolution of various quantities. Although cost-optimal reachability is decidable (in polynomial space) on this model, it becomes undecidable on weighted timed games. This paper studies cost-optimal reachability problems on weighted timed automata and games under robust semantics. More precisely, we c...

Using an automata-theoretic approach, we investigate the decidability of liveness properties (called Presburger liveness properties) for timed automata when Presburger formulas on configurations are allowed. While the general problem of checking a temporal logic such as TPTL augmented with Presburger clock constraints is undecidable, we show that there are various classes of Presburger liveness...

Timed automata are nite-state machines constrained by timing requirements so that they accept timed words | words in which every symbol is labeled with a real-valued time. These automata were designed to lead to a theory of nite-state real-time properties with applications to the automatic veri cation of real-time systems. However, both deterministic and nondeterministic versions su er from dra...

This paper establishes a relationship between reachability problems in timed automata and space-bounded counter automata. We show that reachability in timed automata with three or more clocks is naturally logarithmic-space interreducible with reachability in spacebounded counter automata with two counters. We moreover show the logarithmic-space equivalence of reachability in two-clock timed aut...

In this paper we define and study the class of stopwatch automata which are timed automata augmented with stopwatches and unobservable behaviour. In particular, we investigate the expressive power of this class of automata, and show as a main result that any finite or infinite timed language accepted by a linear hybrid automaton is also acceptable by a stopwatch automaton. The consequences of t...