Synchronous/anytime programming for distributed reactive systems

In this paper, we first propose a mixed synchronous/asynchronous programming model for distributed reactive systems. This model is built around a set of synchronous reactive kernels, written in Esterel synchronous language, each of them controlling a set of asynchronous and time-consuming tasks, through a set of tasks control directives. In this paper, we focus on protocols allowing the implementation of a set of synchronous reactive kernels on a distributed machine. These protocols are based on a model of computation named the “weak synchronous hypothesis”, assuming that reaction times and communication times of the synchronous network can be upper bounded at compile-time. In order to validate this programming model, we have developed a compiler allowing the expression of a real-time application as a set of distributed reactive kernels, written in Esterel synchronous language. The compiler automatically produces a simulator of the real-time application, written in C language and running on a Unix workstation. Finally, we describe preliminary results we have obtained on actual applications, taken from associate avionics systems