AT&T 555-600-736 manual Automated Attendant Ghost Calls and Loop-Start Facilities

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The ARS feature also isolates the station user from the specific trunk, and even the group of trunks. that carries each outgoing call. Other features. such as Callback Queuing (LEGEND) or Busy-to-Idle (System

25)reminders, allow station users to seize trunks moments after a previous conversation concludes, and easily fast enough to beat a ringing signal on an incoming call.

The glare problem can also be compounded if the PBX customer has terminals or computers that place outgoing data calls without human supervision. If a terminal seizes a line for an outgoing call and

encounters glare it will probably disconnect (hanging up on the incoming caller), record a line failure. and try again. The data user may become annoyed that a call attempt failed, but will never know about the rude

reception that was just given to a potential customer.

Automated Attendant Ghost Calls and Loop-Start Facilities

Several customers with loop-start facilities and the Automated Attendant have reported problems with ghost calls. The human attendant who handles overflow calls from the Automated Attendant will notice that often, when the phone rings there will be no one there. or occasionally the attendant will pick up the ringing phone and hear dial tone.

The problem is caused by the fact that the Central Office does not send a reliable signal to force a disconnect at the telephone terminal when only one party on a loop-start line call hangs up. Until the second party hangs up, the loop-start line is considered in use by the CO, and can not be used to receive a new call. This happens sometimes with ground-start trunks as well, since there is usually 20-40 seconds for front end disconnect to pass through.

Consider the case of an automobile dealer that uses the Automated Attendant to direct calls to the new car sales, used car sales, parts, and service departments. During the course of the day, the alder will receive several calls from people who, for one reason or another, hang up while waiting for the Automated Attendant.

Since there is no positive disconnect on loop-start facilities, (the CO does not signal the set to hangup), the central office will continue to hold up the connection to the PBX. When this “connection” reaches the Automated Attendant, the usual list of dial-selectable destinations will be recited, but since there is no longer anyone on the call there will be no response. The Automated Attendant will time out and, in the absence of a positive response, it will assume that it is dealing with a caller who has a rotary dial phone. It will then forward the abandoned call to the human backup attendant. This person's phone will ring, but there won't be anyone there. The condition can also give the perception that the caller was cutoff.

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Contents AT&T Merlin Legend Communications System Application Notes Page Merlin Legend Trunking Concepts Application Note Index Introduction to Trunking Concepts TIP and Ring ExplainedLines and Trunks LOOP-START Trunks Operations LOOP-START Trunks POTENTIAL-PROBLEMS Problem of GlareAutomated Attendant Ghost Calls and Loop-Start Facilities Unavoidable Loop-Start Facility Applications LOOP-START Trunks When to USE LOOP-START TrunksProper Loop-Start Facility Applications Cost GROUND-START Trunks Operations GROUND-START Trunks Potential Problems GROUND-START Trunks When to USE GROUND-START TrunksDirect Inward Dialing did Trunks Operational Characteristics Did Trunk Signaling Characteristics Types of Loop Reverse-Battery SignalingAdministration Considerations in Using did Trunks Simple Tie Trunk Operation When to USE did TrunksTIE Trunks Tandem Tie Trunk Operation Transferring Calls Signaling and ImplementationTIE Lines P E Transmit C E I V E ON-HOOK OFF-HOOK OFF Premises Stations Page DS1 Service Overview and OperationsDESIGN, Signaling & Implementation Potential Problems/LimitationsData Communications Equipment Do GBS Customers Need T-1?Channel Service Unit CSU Multiplexer MUX DS1 Facility Services IsdnSDN SID/ANI Operation Overview Maintenance and TroubleshootingSpecial HOTEL/MOTEL Trunks Hardware Module LINE/TRUNK Station Type Specifications TTR Trunk analog voice Reusable Modules from Merlin II R3 Administration ConsiderationsReferences