3Com Switch 7750 Configuration Guide Guide

100 CHAPTER 11: VOICE VLAN CONFIGURATION
For tagged packets sent by the IP voice devices, processing modes in the two
modes are the same, that is, tagged packets are only forwarded and no MAC
address is learnt.
Voice VLAN packets can be forwarded by trunk ports and hybrid ports in voice
VLAN. You can enable a trunk port or a hybrid port belonging to other VLANs to
forward voice and service packets simultaneously by enabling the voice VLAN
function for it.
As multiple types of IP voice devices exist, you need to match port mode with
types of voice stream sent by IP voice devices, as listed in
Table 50.
Tabl e 50 Matching relationship between port modes and voice stream types
Port voice VLAN
mode
Voice stream type Port type Supported or not
Automatic mode
Tagged voice stream
Access Not supported
Trunk
Supported
Make sure the default
VLAN of the port
exists and is not a
Voice VLAN. And the
access port permits
the packets of the
default VLAN.
Hybrid
Supported
Make sure the default
VLAN of the port
exists and is in the list
of the tagged VLANs
whose packets are
permitted by the
access port.
Untagged voice
stream
Access Not supported,
because the default
VLAN of the port
must be a voice VLAN
and the access port is
in the voice VLAN. To
do so, you can also
add the port to the
voice VLAN manually.
Trunk
Hybrid