Installation guide

Configuring External Numbers Dialing Plan
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ShoreTel 14.2 Planning and Installation Guide 107
Changing Extension Length
The ShoreTel system supports 3-, 4-, and 5-digit extensions.
Complete the following steps to change the extension length:
1. Click Increase Extension Length.
2. Specify 4 or 5 digits for the increased length.
If your system uses 3-digit extensions, ShoreTel recommends that you do not assign x11 extensions to
users.
Configuring External Numbers
The ShoreTel system supports 1-, 2-, and 3-digit trunk access codes. When an access code is dialed,
the system looks for a valid digit in the parameters.
If an invalid number is dialed, the system plays a recording to the calling party.
There are several types of valid telephone numbers, which are described in the following sections.
The ShoreTel system allows the system administrator to provide users at each site with a unique
dialing plan to match the dialing plan of the site’s geographic region. The ShoreTel system supports 7-
digit local dialing, 10-digit local dialing, and mixed local dialing.
External numbers are converted into a standard “canonical format” by call control software to provide a
globally consistent way of handling phone numbers. The canonical format starts with a “+”
representing the international prefix, followed by the country code, area code, and subscriber number.
 External numbers that can be converted into canonical format are considered “routable” and will
leverage the network call routing feature of the call control software.
 External numbers that are unique to the country (n11, 112, 911, and so on) are considered
“unroutable” and will not leverage the network call routing software. These calls will be placed from
the local site or the associated proxy site.
Configuring 7-Digit Local Dialing
The Local Area Code on the Site edit page, shown in Figure 13, defines 7-digit dialing for all users at
the site. When a user dials an access code followed by 7 digits, the switching software assumes the
site local area has been dialed. The switching software then converts the 7-digit number into canonical
format before checking call permissions and doing network call routing.
Note
Once you increase an extension length, you cannot decrease an extension length. For example, once
it is increased to 4, the minimum is 4.