Patent ID: 7830889

Claim:
A system for scheduling traffic, including a plurality of data units, in a network device, comprising: a first scheduler, including a plurality of queues to store the data units, to route the data units to a second scheduler, where the first scheduler and the second scheduler are configured to operate in three different configurable modes selected from: a first mode, in which the first scheduler determines which of a plurality of virtual channel (VC) nodes will route the data units to a corresponding one of a plurality of queues in the second scheduler, based on weights, determined via quality of service (QoS) scheduling, assigned to each of the VC nodes, and in which the second scheduler controls the routing of the data units, from the first scheduler, on a per VC basis; a second mode, in which the first scheduler determines which of the plurality of VC nodes will route the data units directly to an output port, including a buffer, of the second scheduler; and a third mode, in which the first scheduler includes a non-strict priority section that determines which of a plurality of virtual path (VP) nodes will route the data units to a plurality of queues in the second scheduler, based on weights, determined via quality of service (QoS) scheduling, and in which the first scheduler further includes a strict priority section that determines which of a second plurality of VP nodes will route the data units to the plurality of queues in the second scheduler, based on per-data unit strict priority; and the second scheduler is configured to schedule the data units for transmission.