8 bandwidth borrowing, Parent (see – ZyXEL Communications P-660H-D Series User Manual
Page 166
P-660R/H-D Series User’s Guide
165
Chapter 16 Media Bandwidth Management Advanced Setup
• 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.
16.7.5.2 Fairness-based Allotment of Unused and Unbudgeted Bandwidth
The following table shows the amount of bandwidth that each class gets.
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 Prestige 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.
16.8 Bandwidth Borrowing
Bandwidth borrowing allows a child-class to borrow unused bandwidth from its parent class,
whereas maximize bandwidth usage allows bandwidth classes to borrow any unused or
unbudgeted bandwidth on the whole interface.
Enable bandwidth borrowing on a child-class to allow the child-class to use its parent class’s
unused bandwidth. A parent class’s unused bandwidth is given to the highest priority child-
class first. The child-class can also borrow bandwidth from a higher parent class (grandparent
class) if the child-class’s parent class is also configured to borrow bandwidth from its parent
class. This can go on for as many levels as are configured to borrow bandwidth from their
parent class (see
).
The total of the bandwidth allotments for child-classes cannot exceed the bandwidth allotment
of their parent class. The Prestige uses the scheduler to divide a parent class’s unused
bandwidth among the child-classes.
Table 52 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