VLAN Management
Voice VLAN
NOTE
NOTE
Cisco Small Business 200 1. 1 Series Smart Switch Administration Guide
Voice VLAN Triggers
When Dynamic Voice VLAN mode is Auto Voice VLAN enabled based on trigger, it
means Auto Voice VLAN will become operational only if one or more triggers
occur. Possible triggers are static voice VLAN configuration, voice VLAN
information received in neighbor CDP advertisement, and voice VLAN information
received in Voice VLAN Discovery Protocol (VSDP). If desired, an administrator
can make Auto Voice VLAN mode operate immediately without waiting for a
trigger.
When Auto Smartport is enabled depending on Auto Voice VLAN mode, it means
Auto Smartport will be enabled when Auto Voice VLAN becomes operational. If
desired, an administrator can enabled Auto Smartport independent of Auto Voice
VLAN.
The default configuration list here applies to switches whose firmware version
supports Auto Voice VLAN out of the box. It also applies to unconfigured switches
that have been upgraded to the firmware version that supports Auto Voice VLAN.
The defaults and the voice VLAN triggers are designed to have no affect on any
installations without a voice VLAN and on switches that have already been
configured. You may manually disable and enable Auto Voice VLAN and/or Auto
Smartport to fit your deployment if needed.
Auto Voice VLAN
Auto Voice VLAN is responsible to maintain the voice VLAN, but depends on Auto
Smartport to maintain the voice VLAN port memberships. Auto Voice VLAN
performs the following functions when it is in operation:
•
It discovers voice VLAN information in CDP advertisements from directly
connected neighbor devices.
•
If multiple neighbor switches and/or routers, such as Cisco UC devices, are
advertising their voice VLAN, the voice VLAN from the device with the
lowest MAC address is used.
If connecting the switch to a Cisco UC device, you may need to
NOTE
configure the port on the UC device using the switchport voice vlan
command to ensure the UC device advertises its voice VLAN in CDP at the
port.
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