1-3
3) After the IP phone acquires the IP address assigned by DHCP Server2, the IP phone establishes a
connection to the NCP specified by DHCP Server1 and downloads corresponding software. After
that, the IP phone can communicate properly.
z An untagged packet carries no VLAN tag.
z A tagged packet carries the tag of a VLAN.
How the Device Identifies Voice Traffic
The device determines whether a received packet is a voice packet by checking its source MAC
address. Packets with their source MAC addresses complying with the configured OUI (organizationally
unique identifier) addresses are treated as voice packets. Ports receiving packets of this type will be
added to the voice VLAN automatically for transmitting voice data.
You can configure OUI addresses for voice packets or specify to use the default OUI addresses.
An OUI address is a globally unique identifier assigned to a vendor by IEEE. You can determine which
vendor a device belongs to according to the OUI address which forms the first 24 bits of a MAC address.
The WX3000 supports OUI address mask configuration. You can adjust the matching depth of MAC
address by setting different OUI address masks.
The following table lists the five default OUI addresses on the device.
Table 1-1 Default OUI addresses preset on the device
Number OUI address Vendor
1 0003-6b00-0000 Cisco phones
2 000f-e200-0000 H3C Aolynk phones
3 00d0-1e00-0000 Pingtel phones
4 00e0-7500-0000 Polycom phones
5 00e0-bb00-0000 3Com phones
Configuring Operation Mode for Voice VLAN
A voice VLAN can operate in two modes: automatic and manual. You can configure the operation mode
for the voice VLAN according to data traffic passing through a port.