Configuring Voice And Video Parameters; Call Admission Control; Bandwidth-Based Cac; Load-Based Cac - Cisco 2100 Series Configuration Manual

Configuring Voice and Video Parameters

Configuring Voice and Video Parameters
Three parameters on the controller affect voice and/or video quality:
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Each of these parameters is supported in Cisco Compatible Extensions (CCX) v4 and v5. See the
"Configuring Cisco Client Extensions" section on page 6-39
CCX is not supported on the AP1030.
Note
Traffic stream metrics (TSM) can be used to monitor and report issues with voice quality.

Call Admission Control

Call admission control (CAC) enables an access point to maintain controlled quality of service (QoS)
when the wireless LAN is experiencing congestion. The Wi-Fi Multimedia (WMM) protocol deployed
in CCXv3 ensures sufficient QoS as long as the wireless LAN is not congested. However, in order to
maintain QoS under differing network loads, CAC in CCXv4 is required. Two types of CAC are
available: bandwidth-based CAC and load-based CAC.

Bandwidth-Based CAC

Bandwidth-based, or static, CAC enables the client to specify how much bandwidth or shared medium
time is required to accept a new call and in turn enables the access point to determine whether it is
capable of accommodating this particular call. The access point rejects the call if necessary in order to
maintain the maximum allowed number of calls with acceptable quality.
The QoS setting for a WLAN determines the level of bandwidth-based CAC support. To use
bandwidth-based CAC with voice applications, the WLAN must be configured for Platinum QoS. To use
bandwidth-based CAC with video applications, the WLAN must be configured for Gold QoS. Also,
make sure that WMM is enabled for the WLAN. See the
page 4-32
Note You must enable admission control (ACM) for CCXv4 clients that have WMM enabled. Otherwise,
bandwidth-based CAC does not operate properly.

Load-Based CAC

Load-based CAC incorporates a measurement scheme that takes into account the bandwidth consumed
by all traffic types (including that from clients), co-channel access point loads, and co-located channel
interference, for voice applications. Load-based CAC also covers the additional bandwidth consumption
resulting from PHY and channel impairment.
Cisco Wireless LAN Controller Configuration Guide
4-52
Call admission control
Expedited bandwidth requests
Unscheduled automatic power save delivery
for QoS and WMM configuration instructions.
Chapter 4 Configuring Controller SettingsWireless Device Access
for more information on CCX.
"Configuring 802.3 Bridging" section on
OL-17037-01