OPTIMAL APPROACH OF ACHIEVING GROUP-BASED MOBILE MULTIMEDIA-ON-DEMAND SERVICES

摘要

This paper addresses a group-based bandwidth-efficient mobile multimedia-on-demand (GMMOD) service over wireless networks, e.g. multimedia broadcast multicast system (MBMS) and digital video broadcasting network (DVB). In this service model, user's requests are first aggregated or batched and then served over a shared multicast or broadcast channel to achieve the objective of high system satisfactory ratio. We first analyze the tradeoff between service blocking probability and users reneging probability for a basic tirneout-based batching approach. A theoretical model is developed. From this model, we propose an optimal timeout-based approach that is able to identify the optimal tradeoff point that maximizes the system satisfactory ratio at a particular cell status, traffic and user profile. The optimal timeout-based approach is then compared with the previously studied approaches: (1) two basic approaches (timeout-based, size-based), and (2) two hybrid approaches (combined for profit, combined for loss) by simulation. The simulation results demonstrate that the proposed approach gives the better performance in improving the satisfactory ratio and reducing the reneging probability while maintaining a small blocking probability.