How S3100-52P Switch Identifies Voice Traffic - H3C S3100-52P Operation Manual

Operation Manual – Voice VLAN
H3C S3100-52P Ethernet Switch
3) After receiving the DHCP request, DHCP Server 2 residing in the voice VLAN
assigns a new IP address to the IP phone and sends a tagged response message
to the IP phone. After the IP phone receives the tagged response message, it
sends voice data packets tagged with the voice VLAN tag to communicate with the
voice gateway. In this case, the port connecting to the IP phone must be
configured to allow the packets tagged with the voice VLAN tag to pass.
Note:
An untagged packet carries no VLAN tag.
A tagged packet carries the tag of a VLAN.
To set an IP address and a voice VLAN for an IP phone manually, just make sure that
the voice VLAN ID to be set is consistent with that of the switch and the NCP is
reachable to the IP address to be set.

1.1.2 How S3100-52P Switch Identifies Voice Traffic

S3100-52P Ethernet switch determines whether a received packet is a voice packet by
checking its source MAC address against an organizationally unique identifier (OUI) list.
If a match is found, the packet is considered as a voice packet. 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.
Note:
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. S3100-52P Ethernet switch 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 S3100-52P switch.
Table 1-1 Default OUI addresses pre-defined on the switch
Number
1
2
OUI address
0003-6b00-0000
000f-e200-0000
1-3
Chapter 1 Voice VLAN Configuration
Vendor
Cisco phones
H3C Aolynk phones