Energy Efciency of Optimal Transmission Reach for 100G IP-over-WDM Translucent Optical Networks

We investigate the power consumption of IP-over-WDM networks for 100G coherent systems when varying optical reach values. Lightpath bypass and optimal reach saves up to 4%, 27% and 42% in small, medium and large size networks respectively. We also show that "greening" TXPs has a linear-like impact on the reduction of network power consumption. Introduction The "green wave" in telecom networks is pushing designers towards adopting low-consumption devices and networking solutions. IP-over-WDM networks joint with IP router bypass (Bp) are extremely energy efficient with respect to nonbypass (NBp) approach 1,2 . Moreover, newgeneration transponders (TXPs) at 100 Gb/s coherent Polarization-Division-Multiplexed (PDM) Quadrature Phase Shift Keying (QPSK) will be representing an attractive solution since they benefit from extended-reach thanks to advanced digital signal processing (DSP) and from new generation of forward error correction (FEC) systems 3 . Since longer optical reach does not come for free (i.e., TXPs' higher complex circuitry, Raman amplification instead of EDFA, higher fibers' quality, etc..), a network designer must accurately choose whether extended-reach technologies are preferrable to short-reach ones so to prevent from cost and energy waste. In this study we investigate the power consumption of IP-over-WDM networks as a function of systems' optical reach by focusing only on the impact of TXPs. To this aim, we propose a novel power consumption model for 100G TXP depending on next generation FEC's and DSP's complexity.