Abstract: To prevent fraudsters from illicitly collecting the authorization number or authorization code, as well as personal identification number, of an unsuspecting authorized user of a public pay phone, the instant invention disables the keypad of the telephone so long as the pay phone is connected to an incoming call, unbeknownst to the authorized user who is attempting to dial out from that pay phone, and the user is detected to have lifted the handset of the pay phone to attempt to dial out. An alternative method of ensuring that the authorization code of an unsuspecting user is not misappropriated includes adding a circuit to the circuitry of the telephone to ensure that a true dial tone is provided when the user picks up the handset. If no true dial tone is detected, the keypad of the telephone remains disabled.

Abstract: The present invention advanced voice application system takes advantage of information, or attributes, built into a telecommunications network to determine the risk that a call is a fraudulent call in a voice recognition and verification system. To achieve this end, information relating to the telecommunications network are stored in a database as various risk factors. Thus, depending on the type of risk factors associated with a particular call, the risk assigned to that call can be raised or lowered so that the network would not reject a valid caller even though the voice pattern of the caller does not match exactly with the prestored enrolled voice print of the caller. Such risk assessment allows the management of the network to tighten the security of the system without overburdening the caller with questions and also permits calls to be completed for valid subscribers that otherwise would have been rejected.