US Patent 7653069 Two stage queue arbitration

In a node to forward data on a switch fabric, a method that includes scheduling the forwarding of data associated with one of a plurality of traffic classes. The data is to be transmitted through one of a plurality of ports coupled to the switch fabric, each port to be associated with a queue to store data to be forwarded from that port. The scheduling is to include a two stage arbitration scheme. The first stage is to select one queue associated for each traffic class. The second stage is to select one queue from among the queues selected for each traffic class selected in the first stage.