3Com V3000 ANALOG, Installation Manual

Page: 186 / 252

186 C
HAPTER
10: C
ONFIGURING
IP T
ELEPHONY
■
Manually Assigned IP Settings — Use these fields to configure the
IP settings for the telephone. You can change an IP setting only if the
corresponding field under IP Settings Reported by Device is 0.0.0.0. If
the field contains a value other than 0.0.0.0, you can change the
value only through the telephone buttons. See the next section.
Manually assigned settings take precedence over settings assigned
automatically by DHCP. If you manually enter the IP settings for a
telephone, these settings replace any settings supplied by a DHCP server,
and the telephone no longer searches for a DHCP server when it is
plugged into a network.
7 Click OK .
The Ethernet (Layer 2) communications between the NCP and the
telephone ensure that the telephone receives the IP address of the NCP as
part of the configuration.
You can program IP configuration directly into a telephone using the
telephone Local User Interface (LUI) utility. For the 3100 Entry Telephone,
which does not have display panel, you can use the Telephone Local
Configuration application. For detailed instructions on how to use these
tools, see the
NBX Administrator’s Guide .
Automatically
Configuring
Telephone IP Settings
When you connect a 3Com Telephone to a network, it searches for a
DHCP server. If the telephone is on the same subnet as the NCP, the
telephone receives the following configuration information from the
NCP:
■
The IP settings (IP address, subnet mask, and default gateway address)
for the telephone to use
■
The IP address of the NCP
The telephone then stops searching for a DHCP sever.
If a telephone is on a different subnet than the NCP and a DHCP server
provides IP settings to the telephone, the telephone cannot communicate
with the NCP until it has the NCP IP address. There are two methods of
providing the NCP IP address to the telephone:
■
Manually configure the NCP IP address into the telephone using the
telephone LUI utility. See
“Manually Configuring Telephone IP
Settings” on page 185 .
■
Provide the IP address to the telephone using DHCP option 184. For an
example of how to configure option 184 on a DHCP server, see