A global timestamp-based approach to enhanced data consistency and fairness in collaborative virtual environments

Sung-Jin Kim, Falko Kuester, K. H. Kim

Abstract: Collaborative virtual environments are rapidly gaining in popularity for the implementation of intuitive workspaces and networked gaming environments. Primary challenges that have to be addressed by these systems are maintaining systemwide data consistency, enabling fair resource sharing and interaction between users, and compensating network latency jitters. This paper investigates two major concurrency problems - (1) fair request handling and (2) systemwide data consistency. A global timestamp-based approach is presented in combination with different implementation models. Both centralized and decentralized approaches to achieving systemwide consistency and fairness are analyzed. To improve the scalability of the approach, hierarchical models are discussed. Implementation of a proof-of-concept system based on a high-level object-oriented real-time programming scheme called TMO is presented.