Patent ID: 8675841

Claim:
A method of operating a telephony service, the method comprising: detecting, at a first mobile switching center, an attempt by a calling device to place a voice call to a recipient device; querying, by the first mobile switching center, a platform to determine whether sufficient credit exists in an account associated with the calling device to establish the voice call based on the call request; receiving, at the first mobile switching center, an indication that the account associated with the calling device has insufficient credit to establish the voice call; and responsive to detecting the attempt by the calling device to place the voice call to the recipient device and receiving the indication that the account associated with the calling device has insufficient credit to establish the voice call: transmitting an instruction to a first device that causes the first device to generate a message for transmission to the recipient device via a second mobile switching center servicing the recipient device without transmitting a call setup request to the second mobile switching center, wherein the message comprises a request to place a call to the calling device.