Demand-Aware Content Distribution on the Internet

The rapid growth of media content distribution on the Internet in the past few years has brought with it commensurate increases in the costs of distributing that content. Can the content distributor defray these costs through a more innovative approach to distribution? In this paper, we evaluate the benefits of a hybrid system that combines peer-to-peer and a centralized client-server approach against each method acting alone. A key element of our approach is to explicitly model the temporal evolution of demand. In particular, we employ a word-of-mouth demand evolution model due to Bass to represent the evolution of interest in a piece of content. Our analysis is carried out in an order scaling depending on the total potential mass of customers N in the market. Using this approach, we study the relative performance of peer-to-peer and centralized client-server schemes, as well as a hybrid of the two-both from the point of view of consumers as well as the content distributor. We show how awareness of demand can be used to attain a given average delay target with lowest possible utilization of the central server by using the hybrid scheme. We also show how such awareness can be used to take provisioning decisions. Our insights are obtained in a fluid model and supported by stochastic simulations.