Oice Vlan Configuration; Voice Vlan Configuration - 3Com 4200G 12-Port Configuration Manual

12
Voice VLAN
Configuration
Introduction to Voice
VLAN
V VLAN C
OICE
Voice VLANs are VLANs configured specially for voice data stream. By adding the
ports with voice devices attached to voice VLANs, you can perform QoS-related
configuration for voice data, ensuring the transmission priority of voice data stream
and voice quality.
S4200G series Ethernet switches determine whether a received packet is a voice
packet by checking its source MAC address. Voice packets can also be identified by
organizationally unique identifier (OUI) addresses. You can configure an OUI address
for voice packets or specify to use the default OUI address.
An OUI address is a globally unique identifier assigned to a vendor by IEEE. It forms
the first 24 bits of a MAC address.
A voice VLAN can operate in two modes: automatic mode and manual mode. You
can configure the operation mode for a voice VLAN according to data stream passing
through the ports of the voice VLAN.
When a voice VLAN operates in the automatic mode, the switch learns source
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MAC addresses from untagged packets sent by IP phones (an IP phone sends
untagged packets when powered on) and adds the port with the IP phones
attached to the voice VLAN. A port in a voice VLAN ages if the corresponding OUI
address is not updated when the aging time expires.
When a voice VLAN operates in the manual mode, you need to execute related
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commands to add a port to the voice VLAN or remove a port from the voice VLAN.
As for tagged packets sent by IP phones, a switch only forwards them (rather than
learns the MAS addresses) regardless of the voice VLAN operation mode.
Voice VLAN packets can be forwarded by trunk ports and hybrid ports. You can
enable a trunk port or a hybrid port to forward voice and service packets
simultaneously by enabling the voice VLAN function for it.
ONFIGURATION