H3C Technologies H3C WX5500E Series Access Controllers - Manual (Page 150)

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Configuring a voice VLAN
Overview
A voice VLAN is dedicated to voice traffic. After the ports connecting to voice devices are assigned to a
voice VLAN, the system automatically modifies the QoS parameters for the voice traffic. This improves
transmission priority and ensures voice quality.
Common voice devices include IP phones and integrated access devices (IADs). Only IP phones are used
in the voice VLAN configuration examples in this document.
OUI addresses
A device determines whether a received packet is a voice packet by examining its source MAC address.
If the source MAC address of a received packet matches an organizationally unique identifier (OUI) in
the voice device OUI list maintained by the switch, the packet is regarded as a voice packet.
You can remove default OUI addresses and if needed, add them to the OUI list after their removal. You
can add OUI addresses to the OUI list maintained by the device, or use the default OUI list shown
in Table 46 for voice traffic identification.
Table 46 The default OUI list
Number OUI Address Vendor
1 0001-e300-0000 Siemens phone
2 0003-6b00-0000 Cisco phone
3 0004-0d00-0000 Avaya phone
4 00d0-1e00-0000 Pingtel phone
5 0060-b900-0000 Philips/NEC phone
6 00e0-7500-0000 Polycom phone
7 00e0-bb00-0000 3Com phone
An OUI address is usually the first 24 bits of a MAC address (in binary format). It is a globally unique
identifier assigned to a vendor by the IEEE. However, OUI addresses are used by the system to determine
whether received packets are voice packets and they are the results of the AND operation of a MAC
address and a mask in this document. For more information, see " Adding OUI addresses to the OUI list ."
Voice VLAN assignment modes
A port connected to a voice device (for example, an IP phone) can be assigned to a voice VLAN in one
of the following modes:
• Automatic mode—The system matches the source MAC addresses in the untagged packets sent by
the IP phone upon its power-on against the OUI list. If a match is found, the system automatically
assigns the receiving port to a voice VLAN, issues ACL rules, and configures the packet precedence.