US Patent 8442063 System and method for scheduling unicast and multicast traffic

A system and method for scheduling delivery of packetized data traffic at an output port of a network node featuring a hybrid queue with a unicast subqueue and a multicast subqueue. An interleave indicator for each unicast and multicast entry in the queue is used to toggle the header type field of the hybrid queue. Upon departure, a scheduler selects between the unicast subqueue and multicast subqueue as dictated by the state of the header type field. The disclosed interleave indicator techniques add minimal overhead to the system, allowing ready scaling with increasing port densities. Further, the data structure of the multicast subqueue can be selected to optimize the system and achieve desired performance characteristics.