3 application patrol bandwidth management examples – ZyXEL Communications 200 Series User Manual
Page 448
Chapter 27 Application Patrol
ZyWALL USG 100/200 Series User’s Guide
448
Priority and Over Allotment of Bandwidth Effect
Server A has a configured rate that equals the total amount of available bandwidth and a
higher priority. You should regard extreme over allotment of traffic with different priorities
(as shown here) as a configuration error. Even though the ZyWALL still attempts to let all
traffic get through and not be lost, regardless of its priority, server B gets almost no bandwidth
with this configuration.
Finding Out More
• See
for related information on these screens.
• See
for an example of how to set up web surfing policies with
bandwidth restrictions.
27.1.3 Application Patrol Bandwidth Management Examples
Bandwidth management is very useful when applications are competing for limited
bandwidth. For example, say you have a WAN zone interface connected to an ADSL device
with a 8 Mbps downstream and 1 Mbps upstream ADSL connection. The following sections
give some simplified examples of using application patrol policies to manage applications
competing for that 1 Mbps of upstream bandwidth.
Here is an overview of what the rules need to accomplish. See the following sections for more
details.
• SIP traffic from VIP users must get through with the least possible delay regardless of if it
is an outgoing call or an incoming call. The VIP users must be able to make and receive
SIP calls no matter which interface they are connected to.
• HTTP traffic needs to be given priority over FTP traffic.
• FTP traffic from the WAN to the DMZ must be limited so it does not interfere with SIP
and HTTP traffic.
• FTP traffic from the LAN to the DMZ can use more bandwidth since the interfaces
support up to 1 Gbps connections, but it must be the lowest priority and limited so it does
not interfere with SIP and HTTP traffic.
Table 136 Priority and Over Allotment of Bandwidth Effect
POLICY
CONFIGURED RATE
MAX. B. U.
PRIORITY
ACTUAL RATE
A
1000 kbps
Yes
1
999 kbps
B
1000 kbps
Yes
2
1 kbps