Segment wireless voice and data into separate VLANs.
Ensure that Public Secure Packet Forwarding (PSPF) is not enabled for the voice VLAN as this will prevent clients from
communicating directly when associated to the same access point. If PSPF is enabled, then the result will be no way audio.
Cisco Wireless IP Phone 8821 and 8821-EX Wireless LAN Deployment Guide
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