Abstract: A grant scheduler and method for cyclically allocating time slots to traffic container (T-CONTs) included in one or more optical network units (ONUs) for transmitting respective data based on known respective service level agreements for each T-CONT. A first processing unit allocates fixed time slots in a current cycle to a fixed subset of T-CONTs and a second processing unit determines bandwidth demand for each T-CONT in a non-fixed subset of T-CONTs based on a dynamic bandwidth allocation input. A bandwidth allocation unit is coupled to the first processing unit and to the second processing unit for dynamically allocating time slots in the current cycle to the non-fixed subset of T-CONTs based on the determined bandwidth demand and bandwidth availability.