# What’s decidable about parametric timed automata?

@article{Andr2015WhatsDA, title={What’s decidable about parametric timed automata?}, author={{\'E}tienne Andr{\'e}}, journal={International Journal on Software Tools for Technology Transfer}, year={2015}, volume={21}, pages={203 - 219} }

Parametric timed automata (PTAs) are a powerful formalism to reason, simulate and formally verify critical real-time systems. After 25 years of research on PTAs, it is now well understood that any non-trivial problem studied is undecidable for general PTAs. We provide here a survey of decision and computation problems for PTAs. On the one hand, bounding time, bounding the number of parameters or the domain of the parameters does not (in general) lead to any decidability. On the other hand…

## 8 Citations

### What’s decidable about parametric timed automata?

- Computer ScienceInternational Journal on Software Tools for Technology Transfer
- 2017

A survey of decision and computation problems for PTAs, including formalisms close to parametric timed automata (such as parametric hybrid automata or parametric interrupt timedAutomata), and tools dedicated to PTAs and their extensions are studied.

### On the Expressive Power of Invariants in Parametric Timed Automata

- Computer Science2019 24th International Conference on Engineering of Complex Computer Systems (ICECCS)
- 2019

A syntactic restriction on PTAs consisting in removing guards to keep only invariants is proposed to allow for an interesting trade-off between decidability and practical expressiveness and is therefore promising.

### F L ] 1 2 Ju n 20 19 Consistency in Parametric Interval Probabilistic Timed Automata ∗

- Computer Science
- 2019

It is shown that the existence of timing parameter valuations ensuring consistency is undecidable in the general context, but still exhibit a syntactic condition on parameters to ensure decidability.

### Compositional Liveness-Preserving Conformance Testing of Timed I/O Automata - Technical Report

- Computer ScienceFACS
- 2019

An improved version of tioco is proposed, called live timed ioco (ltioco), tackling various weaknesses of existing definitions and extending the theory of zone graphs to enable ltioco testing on a finite semantic model of TIOA.

### 1 J ul 2 01 9 Parametric Verification : An Introduction ⋆

- Computer Science
- 2019

This paper first introduces motivation behind parametric verification in general, and then focuses on different models and approaches, for verifying several kinds of systems, including Parametric Timed Automata, for modelling real-time systems, where the timing constraints are not necessarily known a priori.

### Scenario-Based Online Reachability Validation for CPS Fault Prediction

- Computer ScienceIEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems
- 2020

This article first proposes the concept of parametric hybrid automata (PHA) to describe such complex CPSs, and proposes a mechanism to compose/decompose scenarios to carry out PHA model checking online, as a fault prediction mechanism.

### Parametric Verification: An Introduction

- Computer ScienceTrans. Petri Nets Other Model. Concurr.
- 2019

This paper presents not only the basic formal concepts tackled in the video version, but also an extensive literature to provide the reader with further references covering the area, to introduce motivation behind parametric verification in general and focus on different models and approaches for verifying several kinds of systems.

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