Defining voice vlan – 3Com 2924-PWR User Manual
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ONFIGURING
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UALITY
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ERVICE
Defining Voice
VLAN
Voice VLAN allows network administrators to enhance 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:
■
■
■
Defining Voice VLAN Port Settings
■
Viewing Voice VLAN Port Definitions
■
■