Enhanced dynamic bandwidth allocation in WDM-PON

Abstract

WDM based passive optical network (PON) upgrades current TDM based PON at the architecture, protocol and dynamic bandwidth allocation algorithms to provide higher bandwidth in the access networks. Various Dynamic Wavelength and Bandwidth Allocation algorithms for WDM-PON have been studied. These DWBA algorithms exploit both inter-channel and intra-channel statistical multiplexing in order to achieve better performance, especially when the load on various channels is not symmetric. However, these algorithms let all ONUs share all wavelengths equally, and decouple bandwidth allocation from the wavelength assignment, which may cause bandwidth fragmentation across different wavelengths, and these algorithms further strictly limit the ONUs only to use one wavelength per allocation cycle, hence, leading to the underutilized network performance. To overcome the above limitation, we propose an enhanced dynamic wavelength and bandwidth allocation (EDBA) algorithm, which integrates wavelength assignment with bandwidth allocation process. We use extensive simulation to compare the performance of EDBA to another DWBA algorithm in³.