Cisco Small Business 200 Series Administration Manual page 189

VLAN Management
Voice VLAN
• A phone/endpoint may be statically configured with the voice VLAN.
• A phone/endpoint may obtain the voice VLAN in the boot file it downloads from a TFTP server. A
DHCP server may specify the boot file and the TFTP server when it assigns an IP address to the
phone.
• A phone/endpoint may obtain the voice VLAN information from CDP and LLDP-MED advertisements
it receives from their neighbor voice systems and switches.
The device expects the attaching voice devices to send voice VLAN, tagged packets. On ports where the
voice VLAN is also the native VLAN, voice VLAN untagged packets are possible.
Auto Voice VLAN, Auto Smartports, CDP, and LLDP
Defaults
By factory defaults, CDP, LLDP, and LLDP-MED on the device are enabled, auto Smartport mode is enabled,
Basic QoS with trusted DSCP is enabled, and all ports are members of default VLAN 1, which is also the
default Voice VLAN.
In addition, Dynamic Voice VLAN mode is the default to Auto Voice VLAN with enabling based on trigger,
and Auto Smartport is the default to be enabled depending on Auto Voice VLAN.
Voice VLAN Triggers
When the Dynamic Voice VLAN mode is Enable Auto Voice VLAN, Auto Voice VLAN becomes 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 the Voice
VLAN Discovery Protocol (VSDP). If desired, you can activate Auto Voice VLAN immediately without waiting
for a trigger.
When Auto Smartport is enabled, depending on Auto Voice VLAN mode, Auto Smartport is enabled when
Auto Voice VLAN becomes operational. If desired, you can make Auto Smartport independent of Auto
Voice VLAN.
NOTE
NOTE
Cisco Small Business 200 Series Smart Switch Administration Guide
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 effect 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.
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