In the context of distributed systems, the communication requirements are very different depending on the supported application, the system topology and the environment. The functional electrical stimulation is a critical and real time application domain: communications have to be safe (no loss, neither long nor unexpected delay). Therefore, an important part of this system from an efficiency point of view is the medium access mechanism. To fit with the specific constraints of our context, a new MAC protocol has been designed: STIMAP (Sliding Time Interval based Medium Access Protocol). This article presents a formal validation of this new protocol, allowing the validation of its behavior in an exhaustive way.

Abstract:In the context of real-time fault-tolerant architecture, as TTA (Time-Triggered Architecture), the temporal validation of the system behavior is very important. Indeed, the fault-tolerant mechanism execution must respects several temporal constraints. To validate the mechanism behaviors, and to give their maximum execution time (temporal bound), we propose here a temporal validation methodology for TTA. This methodology uses the UPPAAL tool, based on the timed automata and the model-checking analysis. This methodology allows us to extract the temporal bounds of the TTA services.

National audienceThe reliability of critical real time distributed applications must be guaranty by formal techniques of validation, as the model-checking. However these techniques often lead to combinatory explosion problems. This paper proposes efficient abstractions of the timed automata model of TTA (Time-Triggered Architecture) in a temporal validation context.La fiabilité des applications distribuées temps réel critiques doit être garantie par des techniques formelles de validation, comme le model-checking. Cependant, ces méthodes ont souvent des problèmes d’explosion combinatoire. Cet article propose des abstractions efficaces pour la modélisation et la validation temporelle de l’'architecture TTA (Time-Triggered Architecture) avec des automates temporisés (UPPAAL)