2004. Space uncertain simulation events: some concepts and an application to optimistic simulation

The notion of temporal uncertainty, expressed as the pos-sibility for an event to occur in an interval of simulation time, rather than at a specific instant, has been recently pro-posed and exploited in order to enhance the performance of parallel/distributed simulation systems. In this paper we propose the concept of “spatial uncertainty ” expressed as the possibility for a simulation event to occur in one of a set of points within the simulated system space. How to handle/exploit space uncertain events in an optimistic sim-ulation system is discussed. Also, experimental results for optimistic simulations of a Personal Communication System (PCS) modeled with space uncertain events are reported. These results show the ability of spatial uncertainty to in-crease the performance of the parallel simulation system by providing a more flexible approach to synchronization.