Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.02.xx and greater

4-94
Wireless Local Area Networks (WLANs)
Traffic Management (QoS)
Table 4-8. Priority Values for WMM ACs
By default, the module uses 802.1p priority to place traffic in a queue. You can
choose DSCP instead; see “Customizing Station WMM Parameters” on
page 4-101.
Priority Queuing on Traffic Transmitted from RPs to Wireless
Stations. Remember that all traffic on a radio shares the same medium. So
an RP radio may queue traffic for multiple WLANs together. By default, RPs
queue traffic according to the classification of the WLAN to which it belongs.
Because, by default, this classification is normal for all WLANs, all traffic
receives the same handling.
One way to configure RPs to prioritize the traffic they transmit is to assign
different classifications to traffic in different WLANs. See “Manually Classify-
ing a WLAN’s Traffic” on page 4-109.
For more precise prioritization, you can enable WMM on a WLAN. WMM
allows RPs to queue traffic destined the WLAN according to each frame’s QoS
mark. In other words, the RP uses an 802.1p or DSCP value to assign traffic
to an AC. The RP creates one queue for each AC on each of its radios. The
radio then transmits traffic in that queue using the RP WMM parameters (such
as AIFSN) for that AC. (For more information about the RP WMM parameters
for wired to wireless traffic, see “Viewing and Customizing RP WMM Param-
eters” on page 4-104.)
In this way, traffic with a higher priority receives more bandwidth, as shown
in Figure 4-53. The RP radio continues to provide all wired to wireless traffic
belonging to non-WMM WLANs with normal QoS.
Queue Number AC 802.1p Priority DSCP
1 Background 1, 2 8-23
2 Best Effort 0, 3 0-7. 24-31
3 Video 4, 5 32-47
4 Voice 6, 7 48-63