Scalable and Reliable IPTV Service Through Collaborative Request Dispatching

IPTV has emerged as the future standard of television and drawn enormous attention from both industry and research communities. Among different IPTV services, on-demand services are the most popular ones due to their convenience and rich content. However, supporting scalable and reliable on-demand IPTV services remains to be an important challenge. Existing IPTV architecture dedicates a centralized regional station to serve subscribers in the respective region regardless of temporal and spatial dynamics in service demand. As a result, it may cause significant imbalance of resource utilization and service provisioning delay at different stations, especially with increasing subscribers and video content. In this paper, we propose to allow IPTV stations of different regions to collaboratively serve user requests for delivering scalable and reliable IPTV services. One key challenge in achieving this station-wise collaboration is to route service requests to appropriate stations according to cost-effectiveness and load distribution in a fully distributed manner. We devise a novel request dispatching protocol which runs on each IPTV station, and yet forms a collaborative dispatching strategy that avoids hot spots and reduces service delivery cost at the same time. Our experiment results suggest that our service request dispatching algorithm significantly improves the scalability of on-demand IPTV services for the existing IPTV architecture.