3Com 3C10402B, Administrator'S Manual

Page: 97 / 582

Adding a Remote Telephone 97
Adding a Remote
Telephone
The system software (release R4.2 and higher) supports Network Address
Port Translation (NAPT, also called NAT overloading). NAPT allows you to
put a 3Com Telephone behind a device that applies network address
translation at a remote location, such as a home office, and connect to
the Call Processor through an Internet connection. A typical configuration
is to connect a cable or DSL modem to a small office or home office
router that includes a firewall and Ethernet ports. You connect the 3Com
Telephone directly to one of the Ethernet ports. Another option is use the
pcXset soft telephone application instead of an 3Com Telephone.
Remote NAPT
Telephone
Configuration
This section summarizes the tasks you must complete to configure a
3Com Telephone for operation behind the NAPT device. Because the
configuration interface on each device varies, detailed procedures for
NAPT device configuration are beyond the scope of this document. For
information about configuring the NAPT device, see the documentation
for that device.
To add a broadband connected telephone behind a NAPT device:
1 Make sure the system is set up for IP operations, either Standard IP or IP
On-the-Fly. If you are not using a VPN connection to establish access from
your home system to the system network, the system must have a public
IP address.
2 Use the NBX NetSet utility to enable Auto Discover Telephones
( System-Wide Settings > Auto Discovery ) and then connect the 3Com
Telephone to the system.
Autodiscovering the telephone while it is connected locally to the
network allows the system to configure the telephone in the system
database and assign an extension number. You can manually add the
telephone to the system database instead of using the Auto Discover
feature.
3 Move the telephone to its intended location. Connect it to power and
then use the telephone Local User Interface (LUI) utility to program these
settings:
■
Call Processor MAC address — Required only when the network has
more than one Call Processor.
■
Telephone IP address — A private IP address matching the IP address
scheme on the LAN side of the NAPT device but outside of the DHCP
address range configured in the NAPT device. The telephone must