On bandwidth and storage tradeoffs in multimedia distribution networks

Multimedia distribution on demand will impose extremely severe bandwidth requirements on the distribution network and will require the use of very high capacity video servers. In the context of archival programs playout (typical video-on-demand applications), the information source can potentially be stored at any level in the distribution network. Part of the information may even be duplicated. Of course, there is a tradeoff between the bandwidth required to transport the programs to the users and the storage server capabilities of the overall deployment. The paper presents an analytical study of this tradeoff considering different mechanisms aimed at reducing the overall bandwidth and/or storage server costs. A model of the distribution network is established. A cost function is proposed to capture the different parameters and allow comparison of the possible strategies. Results provide good insight into the problem, and are used to discuss the proper placement of storage in a distribution network