ZyXEL Communications USG-100@USG-200 - V2.20 ED 2 - Application Patrol Bandwidth Management Examples

Chapter 32 Application Patrol
ZyWALL USG 100/200 Series User’s Guide
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So server A gets its configured rate of 300 kbps plus 250 kbps for a total of 550
kbps. Server B gets its configured rate of 200 kbps plus 250 kbps for a total of
450 kbps.
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 Section 6.5.18 on page 110 for related information on these screens.
• See Section 7.7 on page 148 for an example of how to set up web surfing
policies with bandwidth restrictions.
• See DSCP Marking and Per-Hop Behavior on page 385 for a description of DSCP
marking.
32.1.3 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.
Table 146 Maximize Bandwidth Usage Effect
POLICY CONFIGURED RATE MAX. B. U. PRIORITY ACTUAL RATE
A 300 kbps Yes 1 550 kbps
B 200 kbps Yes 2 450 kbps
Table 147 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