Flexible ring-tree TWDM network architecture for next generation optical access network

To achieve higher capacity, longer reach and flexible on-demand wavelength and timeslot provision a ring-tree time and wavelength division multiplexing (TWDM) optical access network architecture is proposed in this paper. Using active remote nodes (RNs) along fiber ring, the pressures from large split and high fiber loss are relieved and add/drop wavelengths at different RNs can be dynamically assigned. By simulations, it is verified that the architecture can provide access services to 8192 optical network units (ONUs) of 70km reach at 10Gbps, and dynamic wavelength and bandwidth allocation (DWBA) can reduce queuing delay and packet loss.