ZyXEL Communications Prestige 662HW Series, Руководство пользователя

Страница: 221 / 458

Prestige 662HW Series User’s Guide
Media Bandwidth Management 20-5
Figure 20-5 Maximize Bandwidth Usage Example
20.7 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
section 20.7.1 ).
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.
20.7.1 Bandwidth Borrowing Example
Here is an example of bandwidth management with classes configured for bandwidth borrowing. The
classes are set up based on departments and individuals within certain departments.