Abstract: A method of authenticating a device for secure communications between the device and a server comprises transmitting a security token request via a data communications network using a data communications protocol. A message is received from the device that no security token is available. In response, an identification request is transmitted from the server to the device via the data communications network and an identification message is received from the device via a mobile communications network using a mobile communications protocol, the identification message including an identification of the device. The identification of the device is stored in a memory. A security token is generated and transmitted to the device via the data communications network. The security token is stored associated with the identification of the device in a memory connected to the server for use in future secure communications with the device via the data communications network.

Abstract: A method of securely processing a transaction includes storing a plurality of encrypted financial transaction instrument identifiers in a memory wherein there is no decryption key for these stored in the memory and further wherein the encrypted financial transaction instrument identifiers are each associated with a mobile communications device. Receiving at a server a request to process a transaction, the request including an identification of a mobile communications device. Retrieving from the memory the encrypted financial transaction instrument identifier associated with the mobile communications device identified in the request. Transmitting the retrieved encrypted financial transaction instrument identifier to the mobile communications device. Receiving from the mobile communications device transaction data and using the received transaction data to effect a financial transaction.