The rise of cloud computing, the wide deployment of mobile device platforms, and the convergence of live, virtual, constructive, and gaming domains require a major shift in synthetic environment exchange and delivery. Traditionally, synthetic environment exchange involves ad-hoc database files in specialized application-targeted formats. That approach does not scale to the whole-earth management necessary to deploy environment content to users across all domains at the point of need. Current web technologies standardized by the Open Geospatial Consortium (OGC) move us closer to the goal of streaming environment delivery. However, these XML-based protocols present bandwidth and latency challenges, particularly for mobile devices, and they lack a caching mechanism for limited or unreliable networks. Furthermore, the current standards lack a unified view of the full environment—five disjoint protocols are required to deliver content to a game engine renderer.
Several ongoing development and standardization efforts aim toward comprehensive synthetic environments designed for simulation and runtime performance requirements. For example, the OGC CDB draft standard defines a binary file-based repository for a multi-resolution runtime environment. The Khronos Group GL Transmission Format (glTF) optimizes binary transmission of streamlined visual content. The Army Research Lab’s Layered Terrain Format (LTF) provides extensible compressed streaming of a comprehensive environment protocol backed by a file cache. To determine the performance gains of these newer approaches over conventional web standards, we need a common methodology for analyzing streaming repository performance. In this paper, we document a methodology to quantify bandwidth, storage, and latency metrics in a consistent manner using open source tools. We prove out this methodology to measure the baseline performance of existing OGC and de facto industry standards with real-world geospatial data. Using this methodology and control group, in future experiments we can properly determine the gains offered by new developments in the synthetic environment domain.