8-32
Cisco Wireless LAN Controller Configuration Guide
OL-17037-01
Chapter 8 Controlling Mesh Access Points
Configuring Advanced Features
Configuring Advanced Features
•
Configuring Voice Parameters in Mesh Networks, page 8-32
•
Enabling Mesh Multicast Containment for Video, page 8-37
Configuring Voice Parameters in Mesh Networks
You can configure call admission control (CAC) and QoS on the controller to manage voice quality on
the mesh network.
Note
Voice is supported only on indoor mesh networks (1130 and 1240 access points).
CAC
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 different
network loads, CAC in CCXv4 or later is required.
Note
CAC is supported in Cisco Compatible Extensions (CCX) v4 or later. See the
“Configuring Cisco Client
Extensions” section on page 6-19
for more information on CCX.
All calls on a mesh access point use bandwidth-based CAC. Load-based CAC is not supported.
Bandwidth-based, or static CAC enables the client to specify how much bandwidth or shared medium
time is required to accept a new call. Each access point determines whether it can accommodate a
particular call by looking at the bandwidth available and compares it against the bandwidth required for
the call. If not enough bandwidth is available to maintain the maximum allowed number of calls with
acceptable quality, the access point rejects the call.
QoS and DSCP Marking
QoS 802.11e is supported on the access and backhaul radios of mesh access points. MAPs can prioritize
client traffic based on the QoS setting defined on the controller. CAC is implemented on the backhaul.
Mesh access points recognize DSCP markings from devices. DSCP is performed on the originating
Cisco 7920 voice handset (client) and the terminating voice handset or terminal. No DSCP marking is
performed on the controller, MAP or CAC.
Note
QoS only is relevant when there is congestion on the network.
You can configure bandwidth-based CAC and QoS for mesh networks using the controller GUI or CLI.
The instructions for configuring these features is the same for both mesh and non-mesh networks with
the exception of QoS settings.