56 CHAPTER 2: DIAL PLAN
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:
1On the Operations tab, click Settings. The Settings dialog box appears.
2Make the desired changes to the extension settings. Tab le 9 describes
each field.
3Click OK to enable your changes and exit the dialog box.
Planning Extension Ranges
By planning extension range on your system, you can accommodate your
present and future needs.
Example: If you initially have 60 telephones and expect to add no more
than 100 additional telephones in the future, choose 100–299 as the
telephone extension range (1000–1199 in a 4-digit system). This
arrangement provides 200 extension numbers to handle the planned
160 telephones plus 40 extra extensions to handle unexpected additions.
Once you set the telephone extension range, you can extend it later,
provided that the new range does not overlap any other number range.
Example: For a 4-digit dial plan, you can set the initial telephone
extension range to 1000–1099. This arrangement allows for up to 100
telephone extensions. Later, you can extend the range up to 3999 to
allow for 400 telephone extensions. By default, the Hunt Group range
starts at 4000 on the SuperStack 3 and 450 on the NBX 100, so you
cannot assign telephone extensions in either of those ranges.
How Auto Discovery
Assigns Extensions
The Auto Discovery process assigns new extensions to telephones and
other devices. For example, if you install a T1 or E1 card, you can use
Auto Discovery to assign extension numbers to each port on the card.
The Auto Discovery process initially assigns a default name (new user) to
each new telephone, and assigns the next available extension number.
Later, you can replace (new user) with the appropriate user’s name.
It is possible to bypass the Auto Discovery process and to manually add a
new telephone and assign an extension. However, 3Com strongly