Patent ID: 8688079

Claim:
A method of establishing a voice communication session, comprising: receiving at a mobile device, over a data channel, an authentication token that can be used to authenticate the mobile device on a voice channel; initiating establishment of the voice channel between a telephony system and the mobile device, the telephony system communicatively coupled with a server; receiving at the mobile device, from the server, on the voice channel, at least one Dual-tone Multi-frequency (DTMF) tone indicating that information about the mobile device was obtained during the establishment of the voice channel and was matched with a database of authorized devices, and responsively sending, from the calling device, on the voice channel, an acknowledgement DTMF tone; proceeding with the voice communication session over the voice channel; and sending from the mobile device, on a data channel, a notification of initiation of a call to be carried on a voice channel, and wherein the authentication code is sent responsive to the notification by the server.