Each phone is configured with 3 call appearance buttons (2 only on ETR phones). These can be used to make both internal and external calls. The dialing of an external call can be indicated by the dialing starting with a specific prefix (9 or 0) if required, otherwise any number not matching an internal extension or function is automatically assumed to be external.

The line used for an outgoing external call is determined by a set of Alternate Route Selection (ARS) settings:

ARS Selectors are created. These are groups of lines or selectors for specific functions using any available ISDN line.

Different classes of call (sets of external number prefixes) are then mapped to those ARS Selectors. The system supports classes for Emergency, National, International, Cell and Toll Free sets of prefixes. An additional Local class is used for any calls that do not match one of the other classes.

When a user dials an external number, it is matched to a selector and uses the function and one of the lines specified by that selector. For SIP trunks set to call by call mode, each call by call entry also has an ARS selector settings which allows it to also be used for outgoing calls.

Line appearances can still be used to make and answer calls on a particular line but are not added by default. They can also be used to select a particular ARS selector for an outgoing call.

Default Alternate Route Selection

The following ARS selectors exist by default. They cannot be deleted though the lines associated with ARS 65 can be edited. By default all the classes of external call are set to use the first available trunk or trunk channel in ARS 65 and 66, that is the first available analog trunk or ISDN trunk channel.

65: Group of Lines
This ARS selector cannot be deleted. By default it contains all analog lines in the system when the system was installed or defaulted. However, it can be edited to change the lines included including adding non-analog lines. This selector and 66 below are used as the default for all classes of external call.

66: ISDN Standard Call - Local Number = Default
This ARS selector cannot be deleted. Calls routed to this selector will use an available ISDN trunk channel with the calling party information set to match the user's User Calling Line Identity if set or otherwise blank (to be set by the trunk provider). This selector and 65 above are used as the default for all classes of external call.

67: ISDN Number Withheld - Local Number = Withheld
This ARS selector cannot be deleted. Calls routed to this selector will use an available ISDN trunk channel with the calling party information set to withheld.

External Dialing Restrictions

A number of methods to restrict which users can make external calls and which numbers they can call are still applied before alternate route selection is used to seize a particular trunk or trunk channel and dial the call.

Allowed Number Lists / Disallowed Number Lists
These lists are used in define numbers that can or cannot be dialed. Users are then associated with the different lists.

Allowed Numbers

Each allowed list contains external telephone numbers that members of the list are allowed to dial. The allowed lists to which a user is assigned override any disallowed lists to which they are also assigned. The numbers in the user's assigned allowed lists also override the Calls Barred and Outgoing Call Restrictions settings that may be applied to a user.

There are eight lists, each containing up to 10 numbers. Each number can use the telephone dialing digits 0 to 9, *, # and can be up to 28 digits long. You can also use the ? character as a single digit wildcard.

Disallowed Numbers

Each disallowed list contains external telephone numbers that users who are assigned to the list cannot dial. There are eight lists, each containing up to 10 numbers. Each number can use the telephone dialing digits 0 to 9, *, # and can be up to 28 digits long. You can also use the ? character as a single digit wildcard.

Numbers in the disallowed lists of which a user is a member are overridden if they also appear in the allowed numbers lists, emergency number list of which the user is a member and also by marked system speed dials.

Emergency Numbers

You can enter 10 emergency phone numbers into this list. This list is applied to all users and overrides any dialing restrictions that may also be applied to the users. Use of numbers in the list can be viewed using a 911-View/E-View button.

Account Codes
Each user can be configured to need to enter a valid account code whenever they make an external call.

Outgoing Call Restrictions
For each user, the type of external calls that the user is able to make can be configured.

Marked Speed Dials
When a user uses a stored system speed dial number, the actual number dialed is subject to all the call barring methods as if the user had dialed the number directly. However system speed dials set as 'marked speed dials' override any call restrictions.  

Night Service
When the system is set to night service, any users in the Night Service Group need to enter the system password when making an external call.