Panasonic Hybrid IP-PBX, Manual

Page: 9 / 40

1.2 Network Management
Information about IP Proprietary Telephones 9
1.2.2 VLAN (Virtual LAN)
VLANs are logical segments within a corporate LAN. By assigning VLAN settings to IP-PTs, it is possible to
separate the packets transmitted by an IP-PT according to the type of data, and specify which VLAN each
data type will be sent over. This allows you to avoid generating unnecessary network traffic on each
segment, and to reduce the load on the network. As a consequence, speech quality can be assured.
Therefore, we recommend to use the VLAN feature to perform VoIP communication effectively.
An IP-PT has two ports for packet communication, primary and secondary. VLAN settings (VLAN ID and
VLAN priority) for the primary port affect voice data transmitted by the IP-PT, whereas VLAN settings for the
secondary port apply to data transmitted by a PC connected to the IP-PT.
Allocating these ports to different VLANs enables you to split the paths for packets from an IP-PT depending
on whether the packet contains voice signals or data. When transmitting packets, the IP-PT can attach
information on which VLAN the packets are to be transmitted over (VLAN Tagging). The switching hub that
receives these packets reads the VLAN information and sends the packets over the appropriate VLAN. This
helps to ensure bandwidth for IP-PT voice transmissions.
In addition, the IP-PT can transmit voice packets with higher priority than other data packets. As this lowers
the rate of loss and delay in transmissions of voice packets, speech quality can be assured to a certain
extent.
Notes
• This VLAN feature complies with IEEE (Institute of Electrical and Electronics Engineers) 802.1Q.
Hybrid IP-PBX
Switching Hub
IP-PT
VLAN 1
VLAN 1
VLAN 1
VLAN 2
VLAN 2
VLAN 1
Segment for Voice Data
VLAN 2
Segment for Other Data
Voice Packet
Other Packet
PC
PC
Primary Secondary
Other Packet
VLAN 2