Reduction of energy consumption of Video-on-Demand services using cache size optimization

Due to its high traffic demand, Video-on-Demand (VoD) is an energy consuming service. Traffic can be reduced by the deployment of caches where the most popular content is stored closer to clients. In this paper, we evaluate the energy consumption of a cache-based VoD service over an IP over WDM network. We develop a Mixed Integer Linear Programming (MILP) model to optimize the cache size for each node in the network at different times of the day. We consider two traffic scenarios with different downlink and uplink ratios. Our results reveal that, using the optimal cache size can reduce the energy consumption by up to 42%.