Prestige 2602H/HW Series User’s Guide

21.5 Scheduler

The scheduler divides up an interface’s bandwidth among the bandwidth classes. The Prestige has two types of scheduler: fairness-based and priority-based.

21.5.1 Priority-based Scheduler

With the priority-based scheduler, the Prestige forwards traffic from bandwidth classes according to the priorities that you assign to the bandwidth classes. The larger a bandwidth class’s priority number is, the higher the priority. Assign real-time applications (like those using audio or video) a higher priority number to provide smoother operation.

21.5.2 Fairness-based Scheduler

The Prestige divides bandwidth equally among bandwidth classes when using the fairness- based scheduler; thus preventing one bandwidth class from using all of the interface’s bandwidth.

21.6 Maximize Bandwidth Usage

The maximize bandwidth usage option (see Section 21.7.2 on page 271) allows the Prestige to divide up any available bandwidth on the interface (including unallocated bandwidth and any allocated bandwidth that a class is not using) among the bandwidth classes that require more bandwidth.

When you enable maximize bandwidth usage, the Prestige first makes sure that each bandwidth class gets up to its bandwidth allotment. Next, the Prestige divides up an interface’s available bandwidth (bandwidth that is unbudgeted or unused by the classes) depending on how many bandwidth classes require more bandwidth and on their priority levels. When only one class requires more bandwidth, the Prestige gives extra bandwidth to that class.

When multiple classes require more bandwidth, the Prestige gives the highest priority classes the available bandwidth first (as much as they require, if there is enough available bandwidth), and then to lower priority classes if there is still bandwidth available. The Prestige distributes the available bandwidth equally among classes with the same priority level.

21.6.1 Reserving Bandwidth for Non-Bandwidth Class Traffic

Do the following three steps to configure the Prestige to allow bandwidth for traffic that is not defined in a bandwidth filter.

1Leave some of the interface’s bandwidth unbudgeted.

2Do not enable the interface’s Maximize Bandwidth Usage option.

3Do not enable bandwidth borrowing on the child-classes that have the root class as their parent (see Section 21.7 on page 270).

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Chapter 21 Media Bandwidth Management Advanced Setup