P-2302HW/HWL-P1 Series User’s Guide

•Research requires more bandwidth but only gets its budgeted 2048 kbps because all of the unbudgeted and unused bandwidth goes to the higher priority sales and marketing classes.

17.1.7.4Fairness-based Allotment of Unused and Unbudgeted Bandwidth

The following table shows the amount of bandwidth that each class gets.

Table 88 Fairness-based Allotment of Unused and Unbudgeted Bandwidth Example

BANDWIDTH CLASSES AND ALLOTMENTS

Root Class: 10240 kbps Administration: 1024 kbps

Sales: 3072 kbps

Marketing: 3072 kbps

Research: 3072 kbps

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 1024 kbps of its budgeted 2048 kbps.

•The ZyXEL Device divides the total 3072 kbps total of unbudgeted and unused bandwidth equally among the other classes. 1024 kbps extra goes to each so the other classes each get a total of 3072 kbps

17.1.8Bandwidth Borrowing

Bandwidth borrowing allows a sub-class to borrow unused bandwidth from its parent class, whereas maximize bandwidth usage allows any bandwidth class to borrow any unused or unbudgeted bandwidth on the whole interface.

Enable bandwidth borrowing on a sub-class to allow the sub-class to use the parent class’s unused bandwidth. The parent class’s unused bandwidth is given to the highest priority subclass first (see Section 17.1.8.1 on page 210).

The total of the bandwidth allotments for sub-classes cannot exceed the bandwidth allotment of the parent class. The ZyXEL Device uses the scheduler to divide the parent class’s unused bandwidth among the sub-classes that have bandwidth borrowing enabled.

Chapter 17 Bandwidth MGMT

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