Maximize Bandwidth Usage Example; Figure 159 Bandwidth Allotment Example - ZyXEL Communications ZyWall 35 User Manual

19.6.2 Maximize Bandwidth Usage Example

Here is an example of a ZyWALL that has maximize 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 159 Bandwidth Allotment Example

The following figure shows the bandwidth usage with the maximize bandwidth usage option
enabled. The ZyWALL 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 ZyWALL also divides the remaining 1 Mbps among the classes that require more
bandwidth. Therefore, the ZyWALL 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 ZyWALL
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 ZyWALL 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.
Chapter 19 Bandwidth Management
ZyWALL 35 User's Guide
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