3Com NBX 100 Administrator's Manual - page 59
Managing Extensions
59
Some countries reserve numbers beginning with 11 for numbers of
national importance. To accommodate this requirement, you can begin
the telephone extension range at 120.
Changing Extension
Length and Ranges
You can view and change extension settings, such as extension length
and extension ranges.
If you are changing from a 3-digit to a 4-digit plan, import the 4-digit dial
plan configuration file before you configure or autodiscover any devices.
To view and change extension settings:
1 On the Operations tab, click Settings. The Settings dialog box appears.
2 Make the desired changes to the extension settings.
Table 10
describes
each field.
3 Click OK to enable your changes and exit the dialog box.
Start External
Discovery At
The extension to use when autodiscovering external devices.
The system assigns extensions starting with this number and
incrementing upward as they are discovered. If the highest
extension is reached, the system starts looking from the
beginning of the external range and selects the first unused one.
Typically, systems do not use all of the available external
extensions from 600–799 in a 3-digit dial plan or from
6000–7999 in a 4-digit dial plan.
Default:
■
4-digit dial plan: 7250
■
3-digit dial plan: 750
External Keyset
Prefix
In Keyset mode, when a button on an NBX Business Telephone
directly accesses an outside line, the NBX system must check
Class of Service. The system prepends the External Keyset Prefix
value (typically 8, 9, or 0) when it makes a call in Keyset mode.
Note 1: The NBX V3000 and the Superstack 3 NBX V5000 are shipped with a
factory default 4-digit dial plan. If you import any 3-digit plan, you must manually
specify any 3-digit extension ranges that are not set by the imported plan. You must
also manually change any device extensions so that they fall within the appropriate
range.
Note 2: The NBX 100 is shipped with a factory default 3-digit dial plan. If you import
any 4-digit plan, you must manually specify any 4-digit extension ranges that are not
set by the imported plan. You must also manually change any device extensions so
that they fall within the appropriate range.
Table 10 Dial Plan Extension Settings (continued)
Field
Purpose (See Notes 1 – 3)