ZyXEL Communications Prestige 662HW Series, User Manual

Page: 220 / 458

Prestige 662HW Series User’s Guide
20-4 Media Bandwidth Management
1.
Leave some of the interface’s bandwidth unbudgeted.
2.
Do not enable the interface’s Maximize Bandwidth Usage option.
3.
Do not enable bandwidth borrowing on the child-classes that have the root class as their parent (see
section 20.7 ).
20.6.2 Maximize Bandwidth Usage Example
Here is an example of a Prestige that has maximized bandwidth usage enabled on an interface. The
first figure shows each bandwidth class’s bandwidth budget and priority. The classes are set up based
on subnets. The interface is set to 10 Mbps. Each subnet is allocated 2 Mbps. The unbudgeted 2 Mbps
allows traffic not defined in one of the bandwidth filters to go out when you do not select the
maximize bandwidth option.
Figure 20-4 Bandwidth Allotment Example
The following figure shows the bandwidth usage with the maximize bandwidth usage option enabled.
The Prestige divides up the unbudgeted 2 Mbps among the classes that require more bandwidth. If the
administration department only uses 1 Mbps of the budgeted 2 Mbps, the Prestige also divides the
remaining 1 Mbps among the classes that require more bandwidth. Therefore, the Prestige divides a
total of 3 Mbps total of unbudgeted and unused bandwidth among the classes that require more
bandwidth.
In this case, suppose that all of the classes except for the administration class need more bandwidth.
Each class gets up to its budgeted bandwidth. The administration class only uses 1 Mbps of its
budgeted 2 Mbps.
Sales and Marketing are first to get extra bandwidth because they have the highest priority (6).
If they each require 1.5 Mbps or more of extra bandwidth, the Prestige divides the total 3
Mbps total of unbudgeted and unused bandwidth equally between the sales and marketing
departments (1.5 Mbps extra to each for a total of 3.5 Mbps for each) because they both have
the highest priority level.
R&D requires more bandwidth but only gets its budgeted 2 Mbps because all of the
unbudgeted and unused bandwidth goes to the higher priority sales and marketing classes.
The Prestige does not send any traffic that is not defined in the bandwidth filters because all of
the unbudgeted bandwidth goes to the classes that need it.