Specifications

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Cisco Aironet 1200 Series Access Point Installation and Configuration Guide
OL-3446-01
Chapter 13 Configuring QoS
Configuring QoS
Step 19 Click the Apply button at the bottom of the page to apply the policies to the access point ports.
Step 20 If you want the access point to give priority to all voice packets regardless of VLAN, click the Advanced
tab. Figure 13-3 shows the QoS Policies - Advanced page.
Figure 13-3 QoS Policies - Advanced Page
Select Enable and click Apply to give top priority to all voice packets.
Adjusting Radio Traffic Class Definitions
The access point uses the radio traffic class definitions to calculate backoff times for each packet. As a
rule, high-priority packets have short backoff times.
The default values in the Min and Max Contention Window fields and in the Slot Time fields are based
on settings recommended in IEEE Draft Standard 802.11e. For detailed information on these values,
consult that standard.
We strongly recommend that you use the default settings on the Radio Traffic Classes page. Changing
these values can lead to unexpected blockages of traffic on your wireless LAN, and the blockages might
be difficult to diagnose. If you change these values and find that you need to reset them to defaults, use
the default settings listed in Table 13-1.
The values listed in Table 13-1 are to the power of 2. The access point computes Contention Window
values with this equation:
CW = 2 ** X minus 1
where X is the value from Table 13-1.