Flexible TDMA/WDMA passive optical network: Energy efficient next-generation optical access solution

Access networks must further advance to address the intensification of the requirements of growing speeds and the usage of Internet applications, and time and wavelength division multiple access (TDMA/WDMA) based passive optical networks (TWDM-PONs) have been widely considered as one of the evolutionary steps of next-generation optical access (NGOA) networks. TWDM-PON combines the flexibility of TDMA with an increased capacity offered by the use of a WDM layer. Moreover, it offers interesting and challenging avenues to minimize energy consumption: especially, with current access networks consuming about 80% of the energy consumed in the Internet. Along with other efforts, reducing energy consumption of central offices is conspicuous as it directly minimizes the operational expenditures of network providers. In this paper, we explore the new paradigms to conserve energy at the central offices in TWDM-PONs. By extensive simulations, we evaluate the possible energy savings in the various flavors of TWDM-PON. Based on the findings, we propose a new architectural flavor of TWDM-PON and benchmark the architecture for cost, power consumption and reach. We also propose a novel energy saving scheme for the proposed architecture and evaluate the impact of the proposed algorithm on energy savings by extensive simulations. (C) 2013 Elsevier B.V. All rights reserved.