VLAN Management
Voice VLA N
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From a VLAN perspective, the above models operate in both VLAN-aware and
VLAN-unaware environments. In the VLAN-aware environment, the voice VLAN is
one of the many VLANs configured in an installation. The VLAN-unaware scenario
is equivalent to a VLAN-aware environment with only one VLAN.
The device always operates as a VLAN-aware switch.
The device supports a single voice VLAN. By default, the voice VLAN is VLAN 1.
The voice VLAN is defaulted to VLAN 1. A different voice VLAN can be manually
configured. It can also be dynamically learned when Auto Voice VLAN is enabled.
Ports can be manually added to the voice VLAN by using basic VLAN
configuration described in the Configuring VLAN Interface Setting section, or by
manually applying voice-related Smartport macro to the ports. Alternatively, they
can be added dynamically if the device is in Telephony OUI mode, or has Auto
Smartports enabled.
Dynamic Voice VLAN Modes
The device supports two dynamic voice VLAN modes: Telephony OUI
(Organization Unique Identifier) mode and Auto Voice VLAN mode. The two
modes affect how voice VLAN and/or voice VLAN port memberships are
configured. The two modes are mutually exclusive to each other.
•Tele ph ony OU I
In Telephony OUI mode, the voice VLAN must be a manually-configured
VLAN, and cannot be the default VLAN.
When the device is in Telephony OUI mode and a port is manually
configured as a candidate to join the voice VLAN, the device dynamically
adds the port to the voice VLAN if it receives a packet with a source MAC
address matching to one of the configured telephony OUIs. An OUI is the
first three bytes of an Ethernet MAC address. For more information about
Telephony OUI, see Configuring Telephony OUI.
•Auto Voice VLAN
In Auto Voice VLAN mode, the voice VLAN can be either the default voice
VLAN, manually configured, or learned from external devices such as
UC3xx/5xx and from switches that advertise voice VLAN in CDP or VSDP.
VSDP is a Cisco defined protocol for voice service discovery.