Loss-aware DR-based update scheduling for improving consistency in DVEs
Maintaining a consistent presentation of the virtual world among participants is a fundamental problem in the distributed virtual environment. The problem is exacerbated due to the limited network bandwidth and error-prone transmission. Using the metric of time-space inconsistency (TSI), we analytically derive the impact of message loss on TSI when using a dead reckoning (DR)-based update mechanism. To improve consistency, a naive algorithm and a compensation algorithm for update scheduling are proposed, in which expected spatial difference and expected TSI are, respectively, calculated by taking message loss into account. Using these algorithms, a budget-based mechanism is developed to meet the network bandwidth constraint. We show through experiments using a racing car game that the budget-based mechanism using the compensation algorithm makes the best use of available network bandwidth to reduce the inconsistency and its impact on the participants, and ensures fairness among participants in spite of widely varying message loss rates. Journal of Simulation (2012) 6, 164-178. doi:10.1057/jos.2012.3; published online 23 March 2012
update scheduling consistency distributed virtual environment message loss dead reckoning bandwidth constraint