On-the-Fly Synthesis of Scarcely Synchronizing Distributed Controllers from Scenario-Based Specifications

Distributed systems consist of subsystems that usually need to coordinate with each other. Each subsystem must decide its actions locally, based on its limited knowledge. However, these decisions can be interdependent due to global requirements, i.e., one subsystem may need to know how another one decided. Complex communication can be required to exchange this knowledge. With rising complexity, a correct manual implementation of all subsystems becomes unlikely. Therefore, our goal is to automate the implementation process as far as possible. This paper presents a novel approach for the automatic synthesis of a distributed implementation from a global specification. In our approach, MSDs—a scenario-based specification language—can be used to intuitively, but formally define the requirements. The resulting implementation comprises one automaton for each subsystem, controlling its behavior. Contrary to similar approaches, we automatically add communication behavior to the system only when local knowledge is insufficient.