Added Value of Introducing Spatial Bypass into WDM/SDM Networks: Gaussian-Noise Model Analysis for Spatially-Bypassed and Spectrally-Groomed Optical Channels

Gaussian-noise model analysis reveals that hierarchical WDM/SDM networks significantky expand the optical reach for spatially-bypassed optical channels up to 2.5 fold, while preserving that for spectrally-groomed optical channels to almost the same level as in conventional single-layer WDM networks.