H3C Technologies H3C S12500 Series Switches - Manual (Page 46)

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Configuring the voice VLAN
Overview
As voice communication technologies grow more mature, voice devices are more and more widely
deployed, especially on broadband networks, where voice traffic and data traffic often co-exist. Usually,
compared to data traffic, voice traffic is given a higher transmission priority for the purpose of reducing
transmission delay and packet loss.
A voice VLAN is configured especially for voice traffic. After assigning the ports connecting to voice
devices to a voice VLAN, the system automatically configures quality of service (QoS) parameters for
voice traffic, thus improving the transmission priority of voice traffic and ensuring 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 chapter.
OUI addresses
A switch determines whether a received packet is a voice packet by checking its source MAC address.
A packet whose source MAC address complies with the voice device’s Organizationally Unique
Identifier (OUI) address is regarded as voice traffic.
In general, as the first 24 bits of a MAC address (in binary format), an OUI address is a globally unique
identifier assigned to a vendor by IEEE. OUI addresses mentioned in this document, however, are
different from those in common sense. OUI addresses in this document are used by the system to
determine whether a received packet is a voice packet. They are the results of the AND operation of the
two arguments mac-address and oui-mask in the voice vlan mac-address command.
You can configure the OUI addresses of a device in advance or use the default OUI addresses. You can
remove the default OUI address of a switch manually and then add new ones manually. Table 1 lists the
default OUI address for each vendor’s devices.
Table 1 The default OUI addresses of different vendors
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