Class-of-service features on the SONET/SDH OC3/STM1 (Multi-Rate) MICs with SFP

The following class-of-service (CoS) features are supported on the SONET/SDH (Multi-Rate) MICs with SFP:

• Preclassification: The preclassifier block classifies the arriving packets. Packets are preclassified into traffic classes (drop precedence and scheduling priority of a packet depend on the traffic class) based on the sources of priority information.
• Ingress behavior aggregate (BA) classification for DiffServ code point (DSCP), IP precedence, and MPLS EXP bits.
• Shaping rates at the queue level.
• Configurable bandwidth profiles with percentages.
• Dynamic bandwidth allocation among different services.
• Scheduler node scaling.
• By default, eight egress queues are created on the physical interface. If per-unit scheduling is not configured, the same eight queues are shared across all logical interfaces.
• Simple ingress policers.
• On MPCs that do not support rich queuing (for example, MX-MPC1-3D), only coarse-grained queuing is provided. Scheduling is available only at the physical interface level and not at the logical interface level.
• On MPCs that support rich queuing (for example, MX-MPC1-3D-Q), the per-unit scheduler statement can be configured on a physical interface only if the encapsulation is Frame Relay. If per-unit scheduling is configured, then each logical interface has eight queues.
• Three levels of scheduling are supported on MPCs that support rich queuing:
• Layer 1: Port level
• Layer 2: Logical interface level
• Layer 3: Queue level
• Delay buffer allocation. By default, 100 ms worth of buffer is available on all the MPCs with and without rich queuing.
• Parameters at the logical and physical interface levels: guaranteed-rate, shaping-rate, and weighted-rate.