Panasonic KX-NCP500, Networking Manual

Page: 17 / 110

2.1.2 Network Configuration
You must evaluate the structure of the existing network to see if a VoIP network can be implemented. Below
are the points that should be evaluated.
Is the IP network a managed network?
A VoIP network should be implemented on a managed IP network such as Frame Relay, Leased Line, or
IP-VPN (Virtual Private Network).
An unmanaged network, such as the Internet (including an Internet VPN), cannot be used to employ a VoIP
network because delays and loss in data transmission can cause huge degradation in speech quality.
Is it possible to have static IP addressing?
IP telephones on the network always perform VoIP communications through the PBX. Therefore, the PBX
must be assigned static IP addresses, which must be programmed to each IP telephone on the network.
Note
When a DHCP server (which automates IP addressing of devices on the network) is not used, static IP
addressing must also be enabled for all IP telephones.
Does only a single router provide access to the IP network?
In a dual network, 2 routers provide access to the IP network as shown in the diagram below. However, only
one router can be used as an access point to the network.
Therefore, in the diagram below, if router A, whose IP address is assigned as the default gateway IP address
of the PBX and the IP telephones, fails, VoIP communications are no longer possible; they are not able to
switch their default gateway from router A to router B to access the IP network.
IP Network
Router A Router B
Default gateway of
the PBX: Router A
Default gateway of
the IP Telephone:
Router A
Document Version 2010-08 IP Networking Guide 17
2.1.2 Network Configuration