Architectural Choices for Video-on-Demand Systems

Cost-effectiveness is of foremost importance for large scale VoD systems. We assume a VoD system where each video is split into two parts, the prefix and the suffix. We consider two new architectures: One architecture where the clients are equipped with set-top boxes that allow to store locally the prefix part of some/all popular videos and second architecture where the suffix is transmitted via satellite. For each architecture, we develop a cost model to compute the delivery cost of videos. We show that these architectures are efficient and significantly reduce the system cost in many scenarios: (i) By more than 45% with set-top boxes at the client side, (ii) By more than 80% for satellite transmission of the suffix.