Dynamic wavelength allocation method consistent with DBA grant for <I>λ</I>-tunable WDM/TDM-PON

At dynamic wavelength allocation (DWA) to optical network units (ONUs) in wavelength-tunable (<I>λ</I>-tunable) wavelength-division-multiplexing/time-division-multiplexing-passive optical networks (WDM/TDM-PONs), consistency between the start time of the wavelength tuning and the upstream grants that are already allocated must be considered. This paper proposes a DWA method that is fully consistent with the dynamic bandwidth allocation (DBA) grant. By inserting a non-allocation period in which the upstream burst signals are halted from reaching the optical line terminal (OLT), the proposed method achieves consistency in a simple manner on the OLT side. Theoretical evaluation shows that the proposed DWA method is suited to <I>λ</I>-tuning for load balancing among the optical subscriber units.