Blueworx Voice Response includes a sample application, which demonstrates how you can use TDM connection management to implement your own applications.
This application is similar to the calling card service provided by many telephone companies. A customer dials in to the calling card application, and enters the telephone number to which they wish to connect. In a real calling card service, the customer would also provide card details and a personal identification number, but these are omitted from the sample application. After the customer has entered a phone number, Blueworx Voice Response places a second call to the specified number, and as soon as this call is answered, the two calls are connected via the TDM bus. The customer can now talk to the called party.
This arrangement is sometimes called a trombone, or hairpin, a reference to the shape of the voice path between the two parties; from the switch to the IVR via one circuit, and returning from the IVR to the switch, via a different, parallel circuit.
Blueworx Voice Response stays on the line during the conversation, and can monitor DTMF key presses made by either party. This feature is not used in the sample application, but in a real service, DTMF keys could be used to request additional services, such as conference calling, or putting a caller on hold.
Blueworx Voice Response also detects when either party hangs up the call. When this happens, the application disconnects the TDM bus connection, makes a short announcement to the remaining party, and then terminates the remaining call.