ZyXEL Communications ZyXEL ZyWALL 2WG - Manual (Page 361)

Chapter 20 Bandwidth Management
ZyWALL 2WG User’s Guide
361
4 If the bandwidth requirements of all of the traffic classes are met and there is still some
unbudgeted bandwidth, the ZyWALL assigns it to traffic that does not match any of the
classes.
20.10 Over Allotment of Bandwidth
It is possible to 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.
20.11 Configuring Summary
Click ADVANCED > BW MGMT to open the Summary screen.
Enable bandwidth management on an interface and set the maximum allowed bandwidth for
that interface.
Table 126 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 7
NetMeeting traffic (Service = H.323): 500 kbps 7
FTP (Service = FTP): 500 Kbps 3