Caller ID

Caller ID is a telephone company service.  It provides the identification information of persons calling your telephone number.  The Caller ID information is supplied by the telephone company between the first and second ring as a series of special codes.  The information includes the time and date of the call, the telephone number of the caller, and, in some areas, a subscription name.

The program uses this Caller ID info to provide detailed information on your incoming calls.  Without Caller ID from your telephone company the program cannot determine the telephone number of incoming calls. 

The program requires a modem that supports Caller ID.  If your modem does not support Caller ID, the caller identification information supplied by the telephone company will not be available to the program software.  Please be advised that the most compatible Caller ID standard is Bellcore, used in the US, Canada, Australia and some other countries.  If your country employs other Caller ID method (like British Telecom CLIP or a widely accepted DTMF Caller ID), you should consult your local phone company if your modem can handle the Caller ID information provided. 

In some areas the telephone company provides Caller ID with name service.  In these areas both the telephone number and name of the calling party are delivered.  The program software is compatible with such service and can use the name information supplied if your telephone company and modem hardware support it.  If your Caller ID service does not include name, you should disable name extension.  Go to Tools -> Options -> Caller ID and select 'Number Only Caller ID Service' checkbox. 

The number is detected by modem hardware when +CID=1 command issued.

Standard Caller ID message packet is being received after first RING in the following way:

RING

DATE = 0321

TIME = 1405

NMBR = 5045551234

NAME = A N OTHER

RING

RING

or, in the case where the tag of the packet is not recognized by the modem

RING

MESG = 060342424231

RING

RING

Sometimes you may receive Private or Out of Area message.  'Private' means that the remote caller decided to block his phone number and personal information.  'Out of Area' means that the telephone exchange was unable to resolve Caller ID information as a call was received from the area which is out of Caller ID service.

ANI stands for "Auomatic Number Identification".  ANI service is mostly used in Russia.  Detecting ANI is much more complicated, because most of existing modems do not provide hardware support for ANI.

ANI signal is being sent after modem takes the call.  So we have the following procedure:

• take the call (ANSWER)
• 200-250 milliseconds delay before requesting ANI
• ANI request (100-200 milliseconds, 500Hz tone)
• receive and decode ANI packet, if any
• emulate 'ring back' tones to the line, so that caller won't know we already took the call

There are some problems.  First, modem hardware is rather slow, and delay between answering and sending request tone can exceed the time ATE will wait for ANI request.  In this case it is recommended to set up TWO request tones in the 'Caller ID Detection' section of 'Properties' dialog.

Then, some ATEs send ANI packet without request.  This means that when we send ANI request, some time will pass and part of the signal will already be transmitted.  Solution is to set 'Pre-detect time' parameter in the 'Caller ID Detection' section of 'Properties' dialog to non-zero value (numbers around 100-200 milliseconds suspected).  It is recommended to set 100 ms when using TWO request tones and 200 ms when issuing only ONE request tone. Generally pre-detect time should be ZERO.

ANI reception and decoding is performed inside of the program, not the modem hardware (if not using 'Hardware' Caller ID type).  This process can be controlled from within 'Actions' section of 'Properties' dialog, but generally there is no need to adjust this stage.

Number of 'ring back' tones emulated to line can be set from within 'Action' section of 'Properties' dialog.  You can also change default action that will be performed after going online and/or emulating N 'ring back' signals to the line.  You may choose from options like 'drop immediately' or 'after N 'ring back' tones'; or it can 'answer', 'set caller on hold' and even switch on 'answering machine'.