Patent ID: 7623451

Claim:
A method of allocating a bandwidth for guaranteeing QoS (quality of service) in an Ethernet passive optical network, the method comprising: at each of a plurality of optical network units (ONUs), classifying uplink frames to be transmitted to an optical line terminal (OLT) into a plurality of classes according to a predetermined priority, and requesting the optical line terminal for a bandwidth according to the plurality of classes; at the optical line terminal, allocating the requested bandwidths for a highest priority class among the plurality of classes; and at the optical line terminal, dynamically allocating bandwidths for a secondary priority class among the plurality of classes using the remained bandwidth after allocating the requested bandwidths to the highest priority class; and at the optical line terminal, dynamically allocating bandwidths for one or more other classes after allocating the requested bandwidth to the highest priority class and the secondary priority class, wherein when a sum of requested bandwidths for the secondary class requested by the optical network units is greater than the remained bandwidth, for each optical network unit, if a smaller value between a predefined maximum usable bandwidth of the optical network unit and a bandwidth requested by the optical network unit is greater than an available bandwidth (avail_BW AF ) to be allocated to the secondary class, the optical line terminal is to allocate a bandwidth to the optical network unit in proportional to a smaller value between a minimum guaranteed bandwidth of the optical network unit and the requested bandwidth requested by the optical network unit.