Distributing RePast Simulations Using Actors

RePast is a well-known agent-based toolkit for modelling and simulation of complex systems. The toolkit is normally used on a single workstation, where modelling, execution and visualization aspects are dealt with. This paper describes an approach aimed to distributing RePast models, with minimal changes, over a networked context so as to address very large and reconfigurable models whose computational needs (in space and time) can be difficult to satisfy on a single machine. Novel in the approach is an exploitation of a lean actor infrastructure implemented in Java. Actors bring to RePast agents migration, location-transparent naming, efficient communications, and a control-centric framework. Actors can be orchestrated by an in-thelarge custom control structure which can ensure the necessary message precedence constraints. Preliminary experience is being carried out using HLA/RTI as middleware. However, the realization can also work with other standard transport layers such as Java Socket and Java RMI. The paper introduces the design rationale behind mapping RePast on to actors and discusses a distributed example.