AT&T MERLIN LEGEND Release 4.0 Feature Reference page 439

Feature Reference
If Automatic Route Selection (ARS) identifies a call as applying to a Call-by-Call
B-channel group but the Call-by-Call Services table does not show a matching
digit pattern and bearer capability, the call is rejected.
Outgoing calls using Call-by-Call Selection Service can be made by pressing a
line button, pressing a Pool button, dialing a trunk pool number, or using ARS.
The Call-by-Call Services Table must be programmed for the Call-by-Call
Service Selection feature to take effect. If a service is not specified in the table,
the entry is ignored.
An SMDR record is not recorded for any call on a PRI 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-PRI facilities
before they are answered. For systems where the majority of lines are PRI lines,
the call length should be programmed for one (1) second.
Feature Interactions
Account Code Entry
Automatic Route
Selection
Barge-In
Enter an account code at an extension assigned to a PRI line before the
call is made or during the call. An account code entered before a call is
treated as an restriction code for all the outgoing calls placed over the
PRI line.
If the SMDR feature is not enabled to record incoming calls, the system
does not accept Account Code Entry information for incoming calls.
An incoming call can access Automatic Route Selection (ARS) only
through Remote Access, transferring, or Remote Call Forwarding
through ARS. A PRI line can be a member of a pool accessed through
ARS. Before ARS routes a call to a pool, it checks whether one or more
member lines in that pool are available. If not, it selects an alternative
pool so that the call is not blocked. Even if a B-channel is available
when ARS selects a pool with an available line, there may be none
available when it is time to send a setup message to the network. Or,
after the setup message is sent, the network may determine that the
B-channel proposed by the system is not available. In either case, the
call fails and fast busy tone is heard.
If an incoming call matches the ARS access code, it is routed to the
extension programmed for unassigned DID calls.
Barge-In can be used on a PRI line. Users cannot Barge-In on a data
call.
Primary Rate Interface (PRI) and T1
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