Cisco Unified Ip Phone 8961, 9951, And 9971 Administration Guide For Cisco Unified Communications Manager - Cisco 9971 Administration Manual

Cisco VXC VPN Limitations and Restrictions
The following limitations and restrictions apply:
• Only Layer 3 packets are tunneled. The Cisco VXC VPN feature does not support Layer 2 tunneling.
• The VPN client supports only IPv4 addresses.
• The Cisco VXC VPN tunnel cannot be established over a Wi-Fi interface.
• The Enable VXC VPN for MAC feature option is configurable only after you set up the phone VPN
• All existing limitations and restrictions that apply to the phone VPN support apply to the Cisco VXC
Do not turn on the VPN before a downgrade to a load previous to 9.2(3), or the phone will be unregistered.
Note
Therefore any Layer 2 capabilities are lost if the Cisco VXC connects through VPN.
parameters, including VPN Group and VPN Profile. This restriction exists because the Cisco VXC VPN
can share the same VPN parameters as the phone VPN.
VPN as well.

Cisco Unified IP Phone 8961, 9951, and 9971 Administration Guide for Cisco Unified Communications Manager 10.0

Cisco VXC VPN Limitations and Restrictions
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