Defining Voice Vlan - 3Com 3CBLSG48 User Manual

Defining Voice
VLAN
Voice VLAN allows network administrators to enhance the VoIP service
by configuring ports to carry IP voice traffic from IP phones on a specific
VLAN. VoIP traffic has a preconfigured OUI prefix in the source MAC
address. Network Administrators can configure VLANs on which voice
IP traffic is forwarded. Non-VoIP traffic is dropped from the Voice VLAN
in auto Voice VLAN secure mode. Voice VLAN also provides QoS to VoIP,
ensuring that the quality of voice does not deteriorate if the IP traffic is
received unevenly. The system supports one Voice VLAN.
There are two operational modes for IP Phones:
IP phones are configured with VLAN-mode as enabled, ensuring
that tagged packets are used for all communications.
If the IP phone's VLAN-mode is disabled, the phone uses
untagged packets. The phone uses untagged packets while
retrieving the initial IP address through DHCP. The phone
eventually use the Voice VLAN and start sending tagged
packets.
This section contains the following topics:
Viewing Voice VLANs

Defining Voice VLAN

Defining Voice VLAN Port Settings
Viewing Voice VLAN Port Definitions
Viewing the OUI Summaries
Modifying OUI Definitions
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