On Designing and Testing Distributed Virtual Environments
This addresses problems for developers of DVE systems, but it is incremental as it builds on existing design concerns without introducing new methods.
The paper analyzes design and testing challenges in Distributed Virtual Environment (DVE) systems, using experiments with OpenSimulator to frame issues across six dimensions like scalability and consistency, but does not report specific numerical results or solutions.
Distributed Real-Time (DRT) systems are among the most complex software systems to design, test, maintain and evolve. The existence of components distributed over a network often conflicts with real-time requirements, leading to design strategies that depend on domain- and even application-specific knowledge. Distributed Virtual Environment (DVE) systems are DRT systems that connect multiple users instantly with each other and with a shared virtual space over a network. DVE systems deviate from traditional DRT systems in the importance of the quality of the end user experience. We present an analysis of important, but challenging, issues in the design, testing and evaluation of DVE systems through the lens of experiments with a concrete DVE, OpenSimulator. We frame our observations within six dimensions of well-known design concerns: correctness, fault tolerance/prevention, scalability, time sensitivity, consistency, and overhead of distribution. Furthermore, we place our experimental work in a broader historical context, showing that these challenges are intrinsic to DVEs and suggesting lines of future research.