Defining CoS Schedulers

The Configure Schedulers page allows you to define CoS schedulers. Using schedulers, you can assign attributes to queues and thereby provide congestion control for a particular class of traffic. These attributes include the amount of Interface Bandwidth, Memory Buffer Size, Shaping Rate, Transmit Rate, and Schedule Priority.

To configure schedulers using the J-Web interface:

  1. Select Configure > Class of Service > Schedulers.

    After you make changes to the configuration in this window, you must commit the changes immediately for them to take effect. To commit all changes to the active configuration, select Commit Options > Commit. See Using the Commit Options to Commit Configuration Changes (J-Web Procedure) for details about all commit options.

  2. Click one of the following:
    • Add—To add a scheduler. Enter information into the schedulers page, as described in Table 34.
    • Edit—To edit a scheduler. Enter information into the schedulers page, as described in Table 34.
    • Delete—To delete an existing scheduler.

Table 34: Schedulers Configuration Page

Field

Function

Your Action

Scheduler name

Specifies the name of a scheduler.

To name a scheduler, type the name; for example, be-scheduler.

Scheduler priority

Sets the transmission priority of the scheduler, which determines the order in which an output interface transmits traffic from the queues.

You can set scheduling priority at different levels in an order of increasing priority from low to high.

A high-priority queue with a high transmission rate might lock out lower-priority traffic.

To specify a priority, select one of the following:

  • high—Packets in this queue are transmitted first.
  • low—Packets in this queue are transmitted last.
  • medium-high—Packets in this queue are transmitted after high-priority packets.
  • medium-low—Packets in this queue are transmitted after low-priority packets.
  • strict-high—Packets in this queue are transmitted first.

Buffer size

Defines the size of the delay buffer.

By default, queues 0 through 7 have the following percentage of the total available buffer space:

  • Queue 0—95 percent
  • Queue 1—0 percent
  • Queue 2—0 percent
  • Queue 3—0 percent
  • Queue 4—0 percent
  • Queue 5—0 percent
  • Queue 6—0 percent
  • Queue 7—5 percent

Note: A large buffer size value correlates with a greater possibility of packet delays. This might not be practical for sensitive traffic such as voice or video.

To define a delay buffer size for a scheduler, select the appropriate option:

  • exact—To specify the exact buffer size.
  • exact-percent—To specify the exact buffer size as a percentage of the total buffer, select exact-percent and type an integer from 1 through 100.
  • percent—To specify buffer size as a percentage of the total buffer, select percent and type an integer from 1 through 100.
  • remainder—To specify buffer size as the remaining available buffer.
  • exact-remainder—To specify the exact buffer size as the remaining available buffer.
  • temporal—To specify buffer size as a temporal value (microseconds).
  • exact-temporal—To specify the exact buffer size as a temporal value (microseconds).

Shaping Rate

Defines the rate of packet transmission.

To define a shaping rate, select the appropriate option:

  • rate—To specify the transmission rate as rate (bits per second), select rate and enter the value ranging from 3200 through 32,000,000,000 bps.
  • percent—To specify a percentage of transmission capacity, select percent and type an integer from 1 through 100.

Transmit rate

Defines the transmission rate of a scheduler.

The transmit rate determines the traffic bandwidth from each forwarding class you configure.

By default, queues 0 through 7 have the following percentage of transmission capacity:

  • Queue 0—95 percent
  • Queue 1—0 percent
  • Queue 2—0 percent
  • Queue 3—5 percent
  • Queue 4—0 percent
  • Queue 6—0 percent
  • Queue 7—5 percent

To define a transmit rate, select the appropriate option:

  • rate—To specify the transmission rate as rate (bits per second), select rate and enter the following value:

    Range: 3200 through 160,000,000,000 bps

  • exact—To enforce the exact transmission rate.
  • exact-percent—To specify the exact percentage of transmission capacity, select exact-percent and type an integer from 1 through 100.
  • percent—To specify a percentage of transmission capacity, select percent and type an integer from 1 through 100.
  • exact-remainder—To specify the exact remaining transmission capacity.
  • remainder—To specify the remaining transmission capacity.