Modulation adaptive grooming in green elastic optical networks

In order to mitigate the mismatch of granularities between fixed grid and client traffic demand, the elastic optical network (EON) was proposed by using orthogonal frequency division multiplexing (OFDM). Bandwidth variable (BV)-transponders consume more fixed power compared with ordinary ones, which will lead to a power-thirsty EON if we do not take any effective measures. Thus the green grooming was proposed for EONs. However, an adaptive multilevel modulation was neglected in the works focusing on green grooming. In this paper, we design a modulation adaptive grooming with guaranteeing transmission performances in green EONs. The simulation results demonstrate that the adaptive multilevel modulation plays a more important role on saving spectrum compared with improving power efficiency for the green grooming in EONs.