Team VerTeCs

Overall Objectives
Scientific Foundations
Application Domains
New Results
Contracts and Grants with Industry
Other Grants and Activities
Inria / Raweb 2003
Project: VerTeCs

Project : vertecs

Section: Scientific Foundations

Keywords : labeled transition systems , symbolic , input/output events , controllable/uncontrollable events , implicit transition relation .

Underlying models.

The formal models we use are mainly automata-like structures such as labelled transition systems (LTS) and some of their extensions: an LTS is a tuple M = ( Q , A , , q o ) where Q is a non-empty set of states; q o Q is the initial state; A is the alphabet of actions, Q × A × Q is the transition relation.

To model reactive systems in the testing context, we use Input/Output labeled transition systems (IOLTS for short). In this setting, interactions between the system and its environment are modeled by input (controlled by the environment) and output events (observed by the environment), and the internal behavior of the system is modeled by internal (non observable) events. In the controller synthesis theory, we also distinguish between controllable and uncontrollable events, observable and unobservable events. In testing, we also manipulate input-output symbolic transition systems (IOSTS), which are extensions of IOLTS that operate on data (i.e., program variables, communication parameters, symbolic constants) through message passing, guards, and assignments. An alternative to IOSTS to specify systems with data variables is the model of synchronous dataflow equations.

Our research is based on well established theories: conformance testing, supervisory control, abstract interpretation, and theorem proving. Most of the algorithms that we employ take their origins in these theories: