Green Routing Algorithms In IP Over WDM Networks

IP over WDM network takes full advantage of huge bandwidth of WDM,which is an effective solution to carry IP traffic.With the expansion of the scale of the network,the network energy consumption increased dramatically,resulting in a large amount of emissions of carbon dioxide and other greenhouse gases that have brought about tremendous pressure on the environment.Consequently,how to design effective green routing algorithms that guarantee network performance while reducing energy consumption and carbon emissions at the same time is a key issue to be solved.In this paper,we focus on the research of green routing algorithm for IP over WDM,and propose two green routing algorithms that consider two factors of renewable energy utilization and holding-time of traffic.And extensive simulations are used for evaluating the effectiveness of the algorithms.In this paper,we first introduce the WDM technology,IP over WDM network model and traffic grooming,analyze the current research of the energy-saving technology in optical network,and summarize the routing algorithms that are based on renewable energy,holding-time-aware of traffic and survivability in WDM networks,respectively.Secondly,with a consideration of holding-time of traffic and mixed use of renewable energy and traditional energy in IP over WDM network,we present the energy consumption model of the network and propose a Hold-time Aware Green Routing Algorithm(HTAGR).With the consideration of holding-time of traffic and renewable energy,this algorithm encourages to choose the path with the least additional traditional energy consumption during the holding-time of traffic,which can reduce the traditional energy consumption and carbon dioxide emissions.Moreover,based on the existing shared protection algorithms,we jointly consider the factors of holding-time of traffic and mixed usage of renewable energy and traditional energy in shared path protection schemes in IP over WDM networks,and propose a Holding-Time Aware Green Shared Path Protection Algorithm(HTAGSPP).This algorithm considers various factors consisting of the used resources in the link,the state of the link,holding-time of traffic and of solar energy supply in the node,and it encourages to choose the path with the least additional traditional energy consumption during the holding-time of traffic as well as to improve the resource ultilization.By means of packing working and protection paths into different optical fibers,the algorithm encourages using active resource as much as possible to build the working path,and using sleep resource as much as possible to build the protection path,which is beneficial to put more equipment into sleeping state to reduce the energy consumption.Finally,based on VC++6.0 software,a IP over WDM simulation platform is developed to evaluate the performance of HTAGR and HTAGSPP,and compare them with the existed algorithms proposed in the previous literatures.The simulation results show that our proposed algorithms can not only maintain low average energy consumption and blocking probability,but also take full advantage of renewable energy and to reduce traditional energy consumption and carbon emissions,which is important to achieve a low-carbon network.