User's Manual

11-7
Cisco 3200 Series Wireless MIC Software Configuration Guide
OL-7734-02
Chapter 11 Configuring QoS in a Wireless Environment
Configuring QoS
Step 10 If you need to assign a priority to filtered packets, use the Filter drop-down menu to select a Filter to
include in the policy. (If no filters are defined on the WMIC, a link to the Apply Filters page appears
instead of the Filter drop-down menu.) For example, you could assign a high priority to a MAC address
filter that includes the MAC addresses of IP phones.
Note The access list you use in QoS does not affect the WMIC’s packet forwarding decisions.
Step 11 Use the Apply Class of Service drop-down menu to select the class of service that the WMIC will apply
to packets that match the filter that you selected from the Filter menu. The WMIC matches your filter
selection with your class of service selection.
Step 12 Click the Add button beside the Class of Service menu for Filter. The classification appears in the
Classifications field.
Step 13 If you want to set a default classification for all packets on a VLAN, use the Apply Class of Service
drop-down menu to select the class of service that the WMIC will apply to all packets on a VLAN. The
WMIC matches all packets with your class of service selection.
Step 14 Click the Add button beside the Class of Service menu for Default classification for packets on the
VLAN. The classification appears in the Classifications field.
Step 15 When you finish adding classifications to the policy, click the Apply button under the Apply Class of
Service drop-down menus. To cancel the policy and reset all fields to defaults, click the Cancel button
under the Apply Class of Service drop-down menus. To delete the entire policy, click the Delete button
under the Apply Class of Service drop-down menus.
Step 16 Use the Apply Policies to Interface/VLANs drop-down menus to apply policies to the Ethernet and radio
ports. If VLANs are configured on the WMIC, drop-down menus for each VLAN’s virtual ports appear
in this section. If VLANs are not configured on the WMIC, drop-down menus for each interface appear.
Step 17 Click the Apply button at the bottom of the page to apply the policies to the ports.
Adjusting Radio Access Category Definitions
The WMIC uses the radio access category 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 Access Categories page,
or that you use the settings described in section x. 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 11-1.
The values listed in Table 11-1 are to the power of 2. The WMIC computes Contention Window values
with this equation:
CW = 2 ** X minus 1
where X is the value from Table 11-1.