WESM zl Management and Configuration Guide WT.01.28 and greater

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Wireless Local Area Networks (WLANs)
Traffic Management (QoS)
Enabling Prioritization of Voice Traffic
Voice prioritization improves the QoS for traffic destined to VoWLAN devices. The
Wireless Edge Services zl Module configures RPs to monitor all packets from stations
in a WLAN; if the IP type in a packet’s header indicates that it is a voice packet, the
module marks all traffic destined to the packet’s source as high-priority voice packets.
Traffic destined to the VoWLAN device thus receives priority handling both in the
Ethernet network (from the wireless services-enabled switch to the RP) and in the
wireless network (from the RP to the VoWLAN device). The wireless services-
enabled switch forwards the traffic in its high-priority queue, and the RP uses its
Voice queue settings.
Voice prioritization thus helps to maintain QoS for VoWLAN devices that do not
support WMM on their own.
To enable the Wireless Edge Services zl Module to prioritize traffic to voice stations
in a particular WLAN, complete these steps:
1. Access the Edit screen for the WLAN that includes voice devices:
a. Select Network Setup > WLAN Setup and click the Configuration tab.
b. Select the WLAN and click the Edit button. The Edit screen is displayed.
2. Under Advanced, check the Use Voice Prioritization box.
3. Click the OK button.
Specifying Multicast Addresses for Voice Traffic
VoWLAN devices often send and listen for traffic on a specific multicast address.
When you specify this address in a WLAN’s settings, the Wireless Edge Services zl
Module prioritizes this traffic.
To specify multicast addresses for voice traffic, complete these steps:
1. Select Network Setup > WLAN Setup and click the Configuration tab.
2. Select the WLAN that includes voice devices, and then click the Edit button. The
Edit screen is displayed.