Extending Renew's Algorithms for Distributed Simulation

Distributed Petri net simulations are still a challenge. A speed up of simulation can be reached, if large applications are distributed over several computers executing a common simulation. Besides technical implementation hinderances, concepts to implement the inherent simulation algorithms in a distributed manner are often missing. Former Renew simulations have been coupled via asynchronous mechanisms like RMI and by general communication frameworks, e.g. for multi-agent applications. In this contribution, we present a simple prototype that supports the atomic synchronous firing of an arbitrary number of transition instances in Renew simulations, distributed over several computers. This is easily modeled with the help of a bidirectional send channel that can traverse simulation boundaries over a network. This channel type is very similar to the synchronous channel of the original Java reference net formalism. However, the unification algorithm is not distributed and cannot be used across send channel calls. The distribution of each algorithm in Renew’s simulation cycle is discussed. The usage of our proposed concepts and tools for distributed simulations of this extended Java reference net formalism are discussed as well.