An Energy Efficient IP over WDM Network

According to recent studies, the power consumption of the Information and Communication Technology (ICT) industry is responsible for about 2 percent of the global CO₂ emissions and this percentage is expected to increase as the internet expands in bandwidth and reach. In this paper we propose a ´hybrid-power´ IP over WDM network where renewable energy is used to reduce the CO₂ emissions. A Linear Programming (LP) model and a novel heuristic are developed to minimize the non-renewable energy consumption in the hybrid-power IP over WDM network. The performance of the network is studied in the USNET topology. Compared with routing in the electronic layer, the results show that routing in the optical layer coupled with using renewable energy significantly reduces the CO₂ emissions of the IP over WDM network by up to 69 percent, and the proposed heuristic hardly affects the QoS. We also develop an LP model to identify the impact of the location of nodes employing renewable energy on the non-renewable energy consumption of the network. Furthermore we investigate the non-renewable energy consumption of the network in different seasons and weather conditions.