Low Carbon Emission IP over WDM Network

In this paper we propose a low carbon emission IP over WDM network where renewable energy is used to reduce the CO₂ emissions at a given energy consumption level. We develop a Linear Programming (LP) model to minimize the non-renewable energy consumption of the network and propose a novel heuristic for improving renewable energy utilization. Compared with routing in the electronic layer, the results show that routing in the optical layer coupled with renewable energy nodes significantly reduces the CO₂ emission of the IP over WDM network by up to 94%, and the new heuristic introduced has little impact on the QoS. In order to identify the impact of the number and the location of nodes that employ renewable energy on the non-renewable energy consumption of the whole network, we also build another LP model. The results show that the nodes at the centre of the network have more impact than other nodes if they use renewable energy sources.