Cisco Cisco 2000 Series Wireless LAN Controller
6
Release Notes for Cisco Wireless LAN Controller and Cisco Lightweight Access Point for Release 3.1.105.0
OL-7431-03
Important Notes
Personnel installing the Wireless LAN Controllers and Cisco lightweight access points must understand
wireless techniques and grounding methods. The internal-antenna Cisco lightweight access points can
be installed by an experienced IT professional.
wireless techniques and grounding methods. The internal-antenna Cisco lightweight access points can
be installed by an experienced IT professional.
Important Notes
This section describes important information about the Wireless LAN Controllers and Cisco lightweight
access points.
access points.
Important Regulatory Notice
The Wireless LAN Controller must be installed by a network administrator or qualified IT professional
and the proper country code selected. Following installation, access to the Wireless LAN Controller
should be password protected by the installer to maintain compliance with regulatory requirements and
ensure proper unit functionality.
and the proper country code selected. Following installation, access to the Wireless LAN Controller
should be password protected by the installer to maintain compliance with regulatory requirements and
ensure proper unit functionality.
Voice WLAN Configuration
Cisco recommends that Load Balancing ALWAYS be turned off in any WLAN that is supporting voice,
regardless of vendor. When Load Balancing is turned on, voice clients can hear an audible artifact when
roaming and the handset is refused at its first reassociation attempt.
regardless of vendor. When Load Balancing is turned on, voice clients can hear an audible artifact when
roaming and the handset is refused at its first reassociation attempt.
Cisco 7920 Wireless IP Phone Support
When using Cisco 7920 Wireless IP phones with Wireless LAN Controllers, make sure that the phones
and Wireless LAN Controllers are configured as follows:
and Wireless LAN Controllers are configured as follows:
•
Aggressive Load Balancing on the Wireless LAN Controllers must be disabled on a per-Wireless
LAN Controller basis. Otherwise, the initial roam attempt by the phone may fail, causing a
disruption in the audio path.
LAN Controller basis. Otherwise, the initial roam attempt by the phone may fail, causing a
disruption in the audio path.
•
The QoS Basis Service Set (QBSS) information element (IE) must be enabled. The QBSS IE enables
the Cisco lightweight access point to communicate its channel usage to wireless devices. Because
Cisco lightweight access points with high channel usage might not be able to handle real-time traffic
effectively, the 7920 phone uses the QBSS value to determine if they should associate with
anotherCisco lightweight access point. Use the following instructions to enable the QBSS IE:
the Cisco lightweight access point to communicate its channel usage to wireless devices. Because
Cisco lightweight access points with high channel usage might not be able to handle real-time traffic
effectively, the 7920 phone uses the QBSS value to determine if they should associate with
anotherCisco lightweight access point. Use the following instructions to enable the QBSS IE:
–
>sh wlan summary
(use this to determine the WLAN ID No. of the WLAN to which you want to add QBSS support)
(use this to determine the WLAN ID No. of the WLAN to which you want to add QBSS support)
–
>config wlan disable [WLAN ID No.]
–
>config wlan dot11-phone compat [WLAN ID No.]
–
>config wlan enable [WLAN ID No.]
–
>sh wlan [WLAN ID No.]
(use this command to verify that the WLAN is enabled and the field marked “Dot11-Phone
Mode (7920)” is in the ‘compat’ mode)
(use this command to verify that the WLAN is enabled and the field marked “Dot11-Phone
Mode (7920)” is in the ‘compat’ mode)
–
>save config