ZyXEL Communications USG 2000 User Manual

 Chapter 32 Application Patrol

ZyWALL USG 2000 User’s Guide

regardless of its priority, server B gets almost no bandwidth with this 
configuration.    

• See 

 for related information on these screens.

• See 

 for an example of how to set up web surfing 

policies with bandwidth restrictions.

• See 

 for a description of DSCP 

marking.

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.

Table 136   Priority and Over Allotment of Bandwidth Effect

A

1000 kbps

Yes

1

999 kbps

B

1000 kbps

Yes

2

1 kbps