AT&T MERLIN LEGEND Release 4.0 Feature Reference page 89

Feature Reference
Pool Button. Like any other type of line/trunk, a BRI line can be
accessed by using a Pool button or by using an SA button and dialing a
pool access code.
Automatic Route Selection. Like any other type of line/trunk, a BRI line
can be accessed by using an SA button and dialing the Automatic Route
Selection (ARS) access code. ARS processing may modify the dialed
number through standard digit deletion and addition processing. ARS
can also take advantage of the distinction between Voice and Data calls
for routing purposes when making outbound calls over BRI lines. For
example, if data is frequently sent to a particular number in another area
of the country, ARS can route calls to that number over high-speed data
lines.
Considerations and Constraints
Because of limitations with the 391A, 391A1, and 391A2 power supplies, the
number of 800 NI-BRI modules plus 100D modules in a single carrier cannot
exceed three. If you have more than three modules, you must install the other
800 NI-BRI or 100D modules in an expansion carrier when using these power
supplies. The 391A3 power supply eliminates this restriction.
A Directory Number (DN) is considered busy when no extensions are available
to answer or cover the call. An extension may be unavailable when: no SA
button (aside from Originate Only buttons) is available; Do Not Disturb is
activated, or the extension is either being programmed, is in forced idle; the
alarm clock is being set. The caller hears a busy tone or the call receives
coverage if programmed.
When using BRI, the SMDR format should be set to ISDN format.
An SMDR record is not recorded for any call on a BRI facility that is less than the
programmed SMDR Call Length. Usually, the SMDR Call Length is programmed
to compensate for connection and ringing time of calls on non-ISDN facilities
before they are answered. For systems where the majority of lines are ISDN
lines, the call length should be programmed for one (1) second.
Feature Interactions
Account Code Entry
Barge-In
Enter an account code at an extension assigned to a BRI line before the
call is made or during the call.
If the SMDR feature is not enabled to record incoming calls, the system
does not accept Account Code Entry information for incoming calls.
Barge-In can be used for a voice call on a BRI line, but not on BRI data
calls.
Basic Rate Interface (BRI)
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