11-14
Cisco Wireless LAN Controller Configuration Guide
OL-17037-01
Chapter 11 Configuring Radio Resource ManagementWireless Device Access
Configuring RRM
The default value is Medium. The DCA sensitivity thresholds vary by radio band, as noted in
.
Step 10
For 802.11a/n networks only, choose one of the following Channel Width options to specify the channel
bandwidth supported for all 802.11n radios in the 5-GHz band:
•
20 MHz
—The 20-MHz channel bandwidth (default)
•
40 MHz
—The 40-MHz channel bandwidth
Note
If you choose 40 MHz, be sure to choose at least two adjacent channels from the DCA
Channel List in
(for example, a primary channel of 36 and an extension channel of
40). If you choose only one channel, that channel is not used for 40-MHz channel width.
Note
If you choose 40 MHz, you can also configure the primary and extension channels used by
individual access points. Refer to the
“Using the GUI to Statically Assign Channel and
Transmit Power Settings” section on page 11-26
for configuration instructions.
Note
To override the globally configured DCA channel width setting, you can statically configure
an access point’s radio for 20- or 40-MHz mode on the 802.11a/n Cisco APs > Configure
page. If you ever then change the static RF channel assignment method to Global on the
access point radio, the global DCA configuration overrides the channel width configuration
that the access point was previously using. It can take up to 30 minutes (depending on how
often DCA is configured to run) for the change to take effect.
This page also shows the following non-configurable channel parameter settings:
•
Channel Assignment Leader
—The MAC address of the RF group leader, which is responsible for
channel assignment.
•
Last Auto Channel Assignment
—The last time RRM evaluated the current channel assignments.
Step 11
In the DCA Channel List section, the DCA Channels field shows the channels that are currently selected.
To choose a channel, check its check box in the Select column. To exclude a channel, uncheck its check
box.
Range:
802.11a—36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 132, 136, 140, 149, 153, 157, 161, 165,
190, 196
802.11b/g—1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
Default:
802.11a—36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 132, 136, 140, 149, 153, 157, 161
802.11b/g—1, 6, 11
Table 11-1
DCA Sensitivity Thresholds
Option
2.4-GHz DCA Sensitivity Threshold
5-GHz DCA Sensitivity Threshold
High
5 dB
5 dB
Medium
15 dB
20 dB
Low
30 dB
35 dB
