"Synchronous Reactive Formalisms"

Esprit "Long Term Research" Project 22703

Selected References


The consortium consists of full partners and associate partners. All full partners are involved in research. Associate partners submit case studies and assess the results. The project is advised by an industrial Steering Committee.

Full Partners

Associate Partners

Industrial Steering Committee


Embedded, safety critical computer systems are of growing importance in our everyday life. They are often called ``reactive systems'' in the literature, since their role is to react to events coming from their physical environment. Embedded control systems for aircraft, railways, or even cars, are well-known examples of reactive systems. Most plants now involve complex reactive systems for monitoring and supervision. Communication protocols or man-machine interfaces are also reactive systems. It is widely recognised that these systems are those whose reliability is the most critical, as design or implementation errors can have disastrous consequences. Therefore, there is a crucial need, in this domain, for clean description formalisms, design and implementation methods and tools, and formal verification.

During the last decade, a family of new languages have been designed, mainly in France, to program such systems. These synchronous languages are based on the abstract point of view that programs instantaneously and deterministically react to input events coming from their environment. A significant amount of research has been driven around these languages, concerning their formal semantics, their compilation, their implementation on distributed architectures, and synchronous program verification.

In the meantime, synchronous programming has started to spread over in the industrial world. With the significant support of industrial users (e.g., Schneider-Electric, Aérospatiale, Dassault-Aviation, Snecma), synchronous programming environments were developed by software companies, like Verilog, Ilog, and TNI. Now, such environments are starting to be used in the large. Thanks to the EUREKA project ``SYNCHRON'' and the Esprit project ``SACRES'', the synchronous technology is now arousing a significant industrial demand from major European companies (SAAB-MA, VTT, SIEMENS, VOLVO, British-Aerospace).

The SYRF project intends to accompany these trends, and to complete these other European projects, by investigating further some long time research tracks: