Patent ID: 7417999

Claim:
A scheduling method for a multi-level class hierarchy wherein classes are represented as nodes in a unified tree, said method comprising: creating a new non-priority node and one or more new priority nodes in said unified tree; selecting non-priority nodes of said unified tree to establish a non-priority sub-tree, wherein said selected non-priority nodes are children of said new non-priority node in said non-priority sub-tree, as viewed in said multi-level class hierarchy; selecting priority nodes of said unified tree to establish one or more priority sub-trees corresponding to one or more priority levels, wherein said selected priority nodes are children of said one or more new priority nodes in said one or more priority sub-trees, as viewed in said multi-level class hierarchy; if and only if queues of nodes of said priority sub-trees are empty, applying a first scheduling algorithm to said non-priority sub-tree to select a packet for transmission; and if any of said one or more priority sub-trees are non-empty, selecting a priority packet from said one or more priority sub-trees for transmission.