Energy-Aware Algorithms for IP Over WDM Optical Networks

To date, the main limitation to the development of telecom networks mainly depended on two factors, namely the cost of the network equipment and transmission. However, nowadays, the enormous spread and growth of the Internet has resulted in a significant increase in the energy consumption of the network equipment. Particularly, the rise in Internet traffic has led to both the increase of the amount of required equipment and the augmentation of energy consumption of such network devices. Consequently, CapEx and OpEx of modern telecommunication networks render the market penetration of such deployment laborious. This surge in power consumption may ultimately lead to an impediment to this continued growth. Since climate change and environmental protection are also of rising concern, many research efforts are being made to raise awareness of environmental issues and reduce the energy footprint of telecommunication networks. In this context, this study targets the reduction of the energy consumption of an IP over WDM backbone network. Already known lightpath bypass and traffic grooming strategies have been used. Although previously proposed schemes based on lightpath bypass approaches and traffic grooming capabilities have been implemented and consequently are able to reduce the overall power consumption of an optical core network, they do not bear in mind, first, the number of the established lightpaths in the virtual topology and second, the exploitation of the residual capacity of the existing lightpaths. This study overcomes the above drawbacks by introducing three novel heuristic schemes which manage to significantly lower the number of the established lightpaths in the virtual topology and take advantage of the remaining capacity of the optical paths by exploiting the lightpaths' resources in a more efficient way. These power-aware heuristics will focus on energy efficiency issues related to the planning and the operation phase of a WDM optical network. Extensive simulation results indicate a promising performance improvement in terms of power consumption when these proposed heuristics are compared to similar, already developed, techniques for energy saving.