Placement of storage capacity in distributed video servers

In this paper, we study how to distribute storage capacity along a hierarchical system with cache-servers located at each node. This system is intended to deliver stored video streams in a video-on-demand way, ensuring that, once started, a transmission will be completed without any delay or loss of quality. We perform a detailed analysis of the start-up time delay for some storage distributions, showing that an "intelligent" storage distribution can increase performance from 22% to 29% with respect to a uniform one and from 44% to 78% with respect to one in which all the storage is attached to the gateway router that connects the final users. We also analyze bandwidth usage, comparing the behavior of these storage distributions.