Port scheduler policies control the traffic behavior on a per-port basis. Associated with each egress port is a set of 8 (eight) class of service (CoS) queues and a default port-scheduler-policy named ‟default”. This default policy makes the port to behave in strict mode. The default policy cannot be modified. The user can attach another policy to the port to change its scheduling behavior.
The scheduler that provides the arbitration across the 8 (eight) CoS queues is a scheduler that is configured in a variety of modes. A major aspect of the arbitration mechanism is the ability to provide minimum and maximum bandwidth guarantees. This is accomplished by tightly integrating a network queue and access egress policies into the scheduler. After the packets are mapped into a COS queue, they are forwarded/conditioned using one of these schedulers (such as Strict Priority (SP), Round-Robin (RR), Weighted Round-Robin (WRR), Weighted Deficit Round-Robin (WDRR), (WRR+SP, WDRR+SP). The traffic shaping aspect is tightly integrated with the scheduler.