ZyXEL Communications P-661H Series - Manual (Page 239)

P-661H/HW Series User’s Guide
Chapter 15 Bandwidth Management 239
• 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.
15.6.2.2 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 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.
15.6.3 Over Allotment of Bandwidth
You can set the bandwidth management speed for an interface higher than the interface’s
actual transmission speed. Higher priority traffic gets to use up to its allocated bandwidth,
even if it takes up all of the interface’s available bandwidth. This could stop lower priority
traffic from being sent. The following is an example.
If you use VoIP and NetMeeting at the same time, the device allocates up to 500 Kbps of
bandwidth to each of them before it allocates any bandwidth to FTP. As a result, FTP can only
use bandwidth when VoIP and NetMeeting do not use all of their allocated bandwidth.
Suppose you try to browse the web too. In this case, VoIP, NetMeeting and FTP all have
higher priority, so they get to use the bandwidth first. You can only browse the web when
VoIP, NetMeeting, and FTP do not use all 1000 Kbps of available bandwidth.
Table 96 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
Table 97 Over Allotment of Bandwidth Example
BANDWIDTH CLASSES, ALLOTMENTS PRIORITIES
Actual outgoing bandwidth available on the interface: 1000 kbps
Root Class: 1500 kbps (same
as Speed setting)
VoIP traffic (Service = SIP): 500 Kbps High
NetMeeting traffic (Service = H.323): 500 kbps High
FTP (Service = FTP): 500 Kbps Medium