Configuring Class of Service for Channelized IQ Interfaces

On channelized IQ interfaces, you can apply class of service at the logical interface level for Frame Relay data-link connection identifiers (DLCIs). To configure class-of-service schedulers at the logical interface level, perform the following tasks:

• Configuring a Class-of-Service Scheduler Map
• Associating the Scheduler with a DLCI on a Channelized IQ Interface

As an alternative to applying class of service at the logical interface level, you can apply rate limiting to the physical interface of a channelized IQ interface. To configure, include the shaping-rate statement at the [edit class-of-service interfaces interface-name] hierarchy level.

Note: For logical interfaces in a channelized IQ interface, you can apply both the shaping-rate statement at the [edit class-of-service interfaces interface-name unit logical-unit-number] hierarchy level and the per-unit-scheduler statement at the [edit interfaces interface-name] hierarchy level. For physical interfaces and channels in a channelized IQ interface, you can configure either the shaping-rate statement at the [edit class-of-service interfaces interface-name] hierarchy level or the per-unit-scheduler statement at the [edit interfaces interface-name] hierarchy level, but not both statements at the same time.

For more information on configuring class of service, see the JUNOS Class of Service Configuration Guide.

Configuring a Class-of-Service Scheduler Map

To configure a class-of-service scheduler map, include the scheduler-map statement at the [edit class-of-service interfaces interface-name unit logical-unit-number] hierarchy level.

To specify the amount of bandwidth allocated to the logical interface, you must also include the shaping-rate statement at the [edit class-of-service interfaces interface-name unit logical-unit-number] hierarchy level. You can specify a peak bandwidth rate in bits per second (bps), either as a complete decimal number or as a decimal number followed by the abbreviation k (1000), m (1,000,000), or g (1,000,000,000). The range is 1000 through 32,000,000,000 bps.

If you do not include the shaping-rate statement in the configuration, the logical interface might not be able to transmit traffic unless surplus bandwidth is available on the physical interface. The sum of the bandwidth you allocate to all the logical interfaces on a physical interface should not exceed the bandwidth of the
physical interface.

Associating the Scheduler with a DLCI on a Channelized IQ Interface

For channelized OC12 IQ, channelized OC3 IQ, channelized DS3 IQ, channelized T1 IQ, channelized STM1 IQ, and channelized E1 IQ interfaces with Frame Relay encapsulation, you can associate a scheduler map name with a logical interface. To activate transmission scheduling on a DLCI, include the per-unit-scheduler statement at the [edit interfaces interface-name] hierarchy level.

You can configure logical interface scheduling on up to 16 channelized interfaces per channelized IQ PIC. For channelized IQ interfaces, the number of schedulers you can apply varies by channel level. Table 9 shows the number of schedulers you can apply at each channel level.

Table 9: Scheduler Limitations for Channelized IQ Interfaces

You can associate up to four forwarding classes per physical interface. Keep in mind that you can configure either a physical interface scheduler or a logical interface scheduler, but not both on the same interface simultaneously.

If you use a Gigabit Ethernet IQ interface, you can apply schedulers on up to 768 VLANs per PIC. For more information on class of service for VLANs on a Gigabit Ethernet IQ interface, see the JUNOS Network Interfaces Configuration Guide.