Energy Minimized design of Mixed Line Rate IP-over-WDM Network

Power consumption in IP-over-WDM networks has become a major concern, more so due to rapidly evolving data intensive applications. Increasing power consumption also increases the environmental cost (carbon emission). Carbon emissions are the result of power generation using non-renewable (traditional hydrocarbons) energy resources. Usage of non-renewable energy resources (such as hydrocarbons, fossil fuel) is a major cause of global warming. An idea to reduce carbon emission is to maximize the use of renewable energy at each node .This not only gives the opportunity to reduce the carbon emission but also leads to development of sustainable infrastructure. Wind and solar are two important resources of renewable energy today. However, green energy generated by these resources is dependent on time of the day and environmental conditions. Since green energy supply is intermittent and not always available, green nodes are backed up by traditional hydrocarbon grid energy. Efficient use of green energy to minimize carbon emission and energy cost is a challenge. We propose MILP (mixed integer linear program) that minimizes the overall non-renewable energy consumption of the MLR WDM network. This MILP model uses mixed-line-rate (MLR) over the single-line-rate (SLR) in WDM. We also compare the non-renewable energy consumption of MLR-WDM network with that of SLR-WDM network. Optimization results indicate that proposed MILP can reduce the overall non-renewable energy consumption of the network up to 35%. In addition, it also reduces the number of transponders used in MLR as compared to SLR networks. Since the number of transponders utilized in the optical layer is directly proportional to the power consumed, therefore with MLR network, non-renewable energy consumption can be reduced in comparison to SLR network. KeywordsIP-over-WDM, SLR, MLR