H3C Technologies H3C WX5500E Series Access Controllers - Manual (Page 161)

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Table 17 How a voice VLAN-enabled port processes packets in security and normal mode
Voice VLAN mode Packet processing mode
Security mode
• For untagged packets and packets that carry the voice VLAN tag:
If the source MAC address of a packet matches an OUI address configured for the
device, it is forwarded in the voice VLAN. Otherwise, it is dropped.
• For packets that carry other tags:
Forwarded or dropped depending on whether the port allows packets of these
VLANs to pass through.
Normal mode
• For untagged packets and packets that carry the voice VLAN tag:
The port does not determine the source MAC addresses of inbound packets. In this
way, both voice traffic and non-voice traffic can be transmitted in the voice VLAN.
• For packets that carry other tags:
Forwarded or dropped depending on whether the port allows packets of these
VLANs to pass through.
Configuration prerequisites
Before you configure a voice VLAN, complete the following tasks:
• Create a VLAN.
• Configure QoS priority settings for voice VLAN traffic on an interface before enabling voice VLAN
on the interface.
If the configuration order is reversed, your priority configuration will fail. For more information, see
"
Configuring QoS priority settings for voice traffic on an interface ."
• Configure the voice VLAN assignment mode.
For more information, see "
Configuring a port to operate in automatic voice VLAN assignment
mode " and " Configuring a port to operate in manual voice VLAN assignment mode ."
Configuration restrictions and guidelines
• You can configure different voice VLANs on different ports at the same time. However, you can
configure one port with only one voice VLAN, and this voice VLAN must be a static VLAN that
already exists on the device.
• You cannot enable voice VLAN on the member ports of a link aggregation group. For more
information about the member ports, see "Configuring Ethernet link aggregation."
• To make voice VLAN take effect on a port that is enabled with voice VLAN and operates in manual
voice VLAN assignment mode, you must assign the port to the voice VLAN manually.
Configuring QoS priority settings for voice traffic on
an interface
In voice VLAN applications, you can improve the quality of voice traffic by configuring the appropriate
QoS priority settings, including the CoS and DSCP values, for voice traffic. Voice traffic carries its own