Reach-related Energy Consumption in IP-over-WDM 100G Networks

In this letter we investigate the power consumption of IP-over-WDM optical networks as a function of 100 Gb/s Transponders' (TXPs) transmission reach when a) two different Multi-Layer design strategies are used, b) the demanded capacity per traffic request increases and c) 100G TXPs are subject to a future possible power consumption reduction. In order to carry out this analysis, we propose a novel methodology to capture the increase of TXP power consumption with optical reach. Simulations on an European-like backbone network show that there exists an optical reach that leads to a minimum network power consumption (i.e., optimal reach). Energy savings brought by the optimal reach depend on the total aggregated traffic, the design strategy and the ratio of the processing costs in terms of Watt/Gb/s between IP and WDM layer. Moreover, we show that the benefits of Multi-Layer design strategy which enables traffic grooming decrease when WDM-layer power consumption decreases and when the demanded capacity per traffic request increases.