A cost-effective distributed architecture for large-scale Video-on-demand'

In spite of the attractiveness of Video-on-demand (VoD) services, their implantation up to the present has not been as widespread as could have been desired, due to centralized VoD systems having a limited streaming capacity and poor scaling. One-level proxy-based systems have been proposed to increase system capacity but their scalability is still limited by the main net bandwidth. To achieve a scalable large-scale system (LVoD), we propose a hierarchical architecture, called double P-Tree, based on a tree topology of independent local nets with proxies. To decentralize architecture and facilitate the system's grow, the functionality of the proxy has been modified in such a way that it works at the same time as cache for the most-watched videos, and as a distributed mirror for the remaining videos. Moreover, the double P-Tree topology interconnects local networks in order to improve connectivity and efficiency. The evaluation of this new architecture, through an analytical model, shows that double P-Tree architecture is a good approach to the design of flexible LVoD systems, without the need for using complex server or high-bandwidth networks.