Chapter 15 Bandwidth Management
P-660HWP-Dx User’s Guide 37

15.5.2 Fairness-based Scheduler

The P-660HWP-Dx 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.
15.6 Maximize Bandwidth Usage
The maximize bandwidth usage option (see Figure 130 on page 40) allows the P-660HWP-Dx
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 P-660HWP-Dx first makes sure that each
bandwidth class gets up to its bandwidth allotment. Next, the P-660HWP-Dx 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 P-660HWP-Dx gives extra
bandwidth to that class.
When multiple classes require more bandwidth, the P-660HWP-Dx 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 P-
660HWP-Dx distributes the available bandwidth equally among classes with the same priority
level.

15.6.1 Reserving Bandwidth for Non-Bandwidth Class Traffic

Do the following three steps to configure the P-660HWP-Dx 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 15.9 on page 41).