Distributed Virtual Environment Architecture Research

The wide use of Distributed Virtual Environment (DVE) technologies in military and various civilian fields presents some new requirements for these systems. The most important one in these requirements is dynamical extensibility which requires supports from two aspects: DVE application systems and communication protocols used among them. NPSNET-V system is a good solution for the former while XRTI meets the latter's needs. The final goal of research in DVE architecture is to solve the problems, to find and to design a platform supporting development of applications based on large-scale shared DVE systems. This can be achieved by integrating NPSNET-V and XRTI systems. NPSNET-V is based on several mature software technologies and characterized by several features such as object-oriented programming, dynamical extensibility, dynamical scalability, open-source development style, flexibility and conveniences in configuration and deployment, and so on. HLA, a mature and advanced technology framework of distributed interactive simulations, has many advantages but a few insufficiencies. Pointing at these shortcomings XRTI puts forward a few improving proposals to HLA standards and a prototype implementation for demonstrating its rationality and necessity. As NPSNET-V and XRTI are all in their prototype stage of research, using them to construct a DVE system needs firstly comprehensions on principles with which they work respectively and extensions to their functions, and then integration of them. Based on analysis of these prototype-stage systems'source code, this paper depicts a clear view on their architectures and functions. For NPSNET-V, research was started from the technologies on which it relies, and how to support dynamical extensibility from architecture level design was worked out. Based on it, the design scheme and implementation of function extension were presented, the pilot and collision detect functions were added into system. After that study focus move to network subsystems. Architecture of XRTI is studied and successfully integrated into NPSNET-V system. XRTI controllers are developed and function correctly. Because...