Configuration Guide 462
Configuring Voice VLAN Overview
1
Overview
The voice VLAN feature is used to prioritize the transmission of voice traffic. Voice traffic
is typically more time-sensitive than data traffic, and the voice quality can deteriorate a lot
because of packet loss and delay. To ensure the high voice quality, you can configure the
voice VLAN and set priority for voice traffic.

Voice VLAN Modes on Ports
A voice VLAN can operate in two modes: manual mode and automatic mode.
Manual mode: This mode is applicable when the switch port forwards voice traffic only.
You manually add ports connecting IP phones to the voice VLAN; then the switch will apply
priority rules to ensure the high priority of voice traffic.
Figure 1-1 Only Voice Traffic on One Port
Internet
IP Phone IP Phone
Switch
Automatic mode: This mode is applicable when voice traffic and data traffic are transmitted
on the same switch port. When a port receives a voice packet, the switch automatically
adds the port to the voice VLAN and applies priority rules. The switch forwards voice traffic
in the voice VLAN and data traffic in other VLANs.
Figure 1-2 Voice Traffic and Data Traffic on the Same Port
Internet
IP PhonePC Switch
To Next Page
Need help?
General