ZyXEL Communications Prestige 662HW Series, User Manual

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Prestige 662HW Series User’s Guide
Media Bandwidth Management 20-3
Figure 20-3 Application and Subnet-based Bandwidth Management Example
20.5 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.
20.5.1 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.
20.5.2 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.
20.6 Maximize Bandwidth Usage
The maximize bandwidth usage option (see Figure 20-7 ) 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.
20.6.1 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.