In this paper, we evaluated energy efficiency for EONs based on the node architecture using flexible multi-flow optical transponders (MF-OTP) that we have proposed. The proposed MF-OTP architecture can flexibly set respective sub-channel's transmission direction to be either upstream or downstream and decide flexible modulation format for each sub-channel, which therefore allows to efficiently transmit asymmetric traffic. With such flexible transmission architecture, we design and evaluate an integer linear programming (ILP) model to optimize the power consumption with considerations on the routing, modulation, spectrum assignment (RMSA). The goal of the ILP model is to find the optimal value for the required number of sub-channels used and the subsequent power consumption.
ACKNOWLEDGMENT This work is supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2017R1A2B1009709 and No. 2018R1D1A1B07051118).