Achieving a Level Playing Field in Distributed Simulations

Remember those days of playing “Cowboys and Indians”? Then you probably also remember having an argument over the outcome of a shooting incident. Some kid would shout: “You’re dead.”, while the assumed victim would firmly acclaim: “No I’m not, you’ve missed me!”. The same argument still happens today in distributed simulations, where individual federates draw conflicting conclusions on the result of weapon engagements or the capabilities of sensors. While one federate assumes that an entity has been killed, another federate still has that same entity alive and kicking. This occurs especially with legacy federates that do their kill assessment internally. To resolve this issue and to achieve a level playing field, each federate should adhere to the simulation agreements and should preferably use identical implementations. Although it is unlikely that all actual details of weapons, sensor systems, etc. will ever become available for reasons of security, commercial or national interest, it is important that an improved and, as a minimum, consistent behavior of these systems is achieved in the virtual theater. This paper introduces the concept of independent handlers that enforce their conclusions upon joined federates. This concept is not restricted to kill assessment, but can also handle the behavior of weapon systems and countermeasure systems. The handlers provide a means to show how to manage security sensitive agreements such as weapon behavior and countermeasures. In this way it helps to achieve a level playing field for all participants in one federation. The paper presents a prototype that shows how to handle such interactions between simulation objects and discusses the ‘lessons learned’ and the way ahead.