Optical-Layer Traffic Grooming in Flexible Grid WDM Networks

In this paper, we introduce an electronic traffic grooming (E-Grooming) technique, and propose a novel bit rate and protocol independent optical-layer traffic grooming (O-Grooming) technique for OFDM-based flexible grid WDM networks. We introduce a novel routing, wavelength assignment, subcarrier assignment, and spectrum allocation (RWSSA) problem for the first time. An effective polynomial-time heuristic algorithms is proposed to address the RWSSA problem in OGrooming capable flexible grid networks. The performance of the proposed E-Grooming and O-Grooming techniques are evaluated with transparent flexible grid networks. Simulation results show that traffic grooming in flexible grid networks improve spectral efficiency compared to transparent networks. In addition to bit rate and protocol transparent, the O-Grooming technique is cost and energy efficient compared to the E-Grooming technique while marginally sacrificing the spectral efficiency.