Near Video-On-Demand with Limited Client Bandwidth and Distributed Servers

Abstract

We investigate the option to implement a near-video-on-demand system in an access network in a distributed way, using the vast amount of available storage capacity at the end users to store the desired movie collection. An important constraint in the network is given by the limited upstream and downstream bandwidth of the end links between the users and the network. We use an improved version of fixed-delay pagoda broadcasting, which can take these constraints into account.

We present a feasible solution for a cable network, in which a fraction of the video data is injected higher up in the network, to improve response times. The solution requires only 18.5 MB of storage and an upstream bandwidth of 125kb/s per user (200,000 users), as well as 84MB of storage at each of the 500 fiber nodes, to implement a near-video-on-demand service of 1000 movies of 100 minutes each, with a response time of less than one second. Furthermore, we analyze the average number of transmission channels, and discuss how adding a little redundancy can make the system more robust.