VoIP Transferring

IVM can transfer calls using VoIP. For VoIP lines it is just a matter of selecting 'Transfer' in the OGM Properties.

Note that only Blind Transfer is supported for VoIP lines.

IVM cannot directly transfer between VoIP and conventional telephone lines without some form of VoIP to PSTN gateway, such as an FXO Adapter or a VoIP gateway provider.

Transferring on PSTN lines

If your telephone company or PBX offers the facility to transfer calls from a normal phone or extension, IVM will be able to transfer calls by dialing the appropriate sequences. The call transfer feature may be branded under trade names by your telephone company (e.g. Telstra's "Business Links" service). If your telephone company does not offer an effective transfer feature, you might be able to use a conference call feature to "simulate" call transfers with IVM (see below).

Before you can setup IVM to do this, you must understand exactly how to transfer a call using an ordinary telephone handset. It is important that you refer to the documentation of your PBX or of the transfer feature of your phone company. The most common system is to press the (hook) flash button to initiate the transfer ("!"), wait for the dial tone (",,,"), dial the number then either hang-up to complete the transfer or press flash again ("!") to retrieve the call.

Overview (How IVM Transfers Calls)

The only connection between IVM and the telephone system is a simple phone line. The only signals IVM can use to transfer calls is dialed digits, a hook-flash ('!') or pauses.

To transfer calls, IVM follows the sequence (as entered using the Transfer tab of Settings) that a person would need to do using a regular phone. (A regular phone is not the same as phone system handsets that are specially wired to the phone system).

Most problems arise when the sequence has not been properly entered (or understood) or where the voice modem or telephony device does not handle hook-flashes correctly (see below). Use the Most Recent Call Log for the line to check IVM is doing what you think it ought to do.

Note: this discussion relates just to real call transfers. VoIP blind transfers are easy and automatic.

Blind Transfer

A blind transfer is a transfer where IVM simply hangs up after making the transfer without waiting to confirm that the transfer was accepted.

Note: You cannot simulate a blind transfer with a conference call feature (see "simulating a confirmed transfer with a conference call" below).
Note: Blind Transfer is currently the only method supported for VoIP lines.

Confirmed Transfer

With a confirmed transfer, the person to whom the call is transferred is given an option to accept or reject the call. If the call is rejected or is not answered, the call is brought back to IVM. If a call is brought back, IVM will execute the transfer fail active command.

With a confirmed transfer you can set the number of times that the prompt is repeated before fail (the default is 7). You can use this to determine the time before fail. However, you must note that the number you enter is not seconds but the prompt repeat count.

Answer Detect Transfer

When this option is selected, IVM initiates the transfer and then waits for the call to be answered. If the call is answered it plays the answering party a short tone then completes the connection. If the call is not answered, the IVM rejects the transfer.

For this to work well the "Answer Detect Settings" must be setup. See Outbound Autodial Calls for more information about this.

Transfer Settings

While the actual transfer number is part of the active command details, the digits to be dialed before and after the transfer number to initiate or complete the transfer must be setup using the Transfer tab of Settings.

The (hook) flash is represented by the '!' character in dial strings. A pause is represented by a ','. We recommend that you always add a pause after a flash when you expect to dial further digits (i.e. '!,') to give time for the dial tone to come on.

Simulating a confirmed transfer with a conference call feature

If your telephone company or PBX does not support call transfers but does support a conference call, IVM can use this feature to "simulate" a transfer. When you tick the "Simulate call transfers as a conference call", IVM will run through the normal steps to setup a conference call (thinking it is transferring the call) and then stay online for the call duration. (Note: Your phone line will be busy for the call duration).

This option is usually only effective with confirmed transfers not blind transfers.