Interoperability issues associated with the use of dissimilar simulators within a DIS network range across a diverse spectrum of concerns. These include differing levels of simulation fidelity, terrain data rendition and correlation, and their relationship to purpose, activity, training efficacy and realism. The Institute for Simulation and Training (IST) is undertaking a two-pronged approach to the study of the interoperability problem. The first prong identifies the primary simulator parameters affecting interoperability and then quantifies them on existing simulators. This is coupled with polling the user community as to whether or not the simulators are perceived to be ‘interoperable.' By doing so IST intends to identify the magnitude of parameter variation deemed acceptable by the user community. The second part of our approach is a research program that quantitatively determines the magnitude of parameter differences at which interaction outcome is affected. The initial investigation in both prongs is limited to consideration of the visual rendition of terrain on image generators within the simulators. In-house studies include tests determining the effect of various magnitudes of terrain mis-correlation on the outcome of combat engagements. The results of both investigations are ultimately combined to define an interoperability test procedure that is applied to networked simulators.

This paper addresses the rationale and approach for assessing interoperability and summarizes the results to date of the experiments and data gathering activities of our research program.