User authentication

1. A method of user authentication by an application on a mobile telephony device, the method comprising:

i. authenticating the user by interaction with the application,

ii. receiving a service code identifying a remote telephony service,

iii. communicating with a remote authentication service to receive a call identifier based on the service code; and

iv. sending the call identifier within a voice telephone call to the remote telephony service, by means of which the user is authenticated to the remote telephony service.

2. The method of claim 1 , including receiving from the remote authentication service a telephone number of the remote telephony service, which telephone number is used to initiate the voice telephone call to the remote telephony service.

3. The method of claim 1 , wherein the service code includes service information, which is included in the call identifier sent within the voice telephone call to the remote telephony service.

4. The method of claim 1 , wherein the remote authentication service communicates the call identifier to the remote telephony service.

5. The method of claim 1 , wherein the remote authentication service requests the call identifier from the remote telephony service.

6. The method of claim 1 , wherein the service code is received by local input to the mobile telephony device.

7. The method of claim 6 , wherein the service code is received by capturing a machine readable code by means of the mobile telephony device.

8. The method of claim 6 , wherein the service code is received by user input.

9. The method of claim 1 , wherein the service code is obtained from an application on the mobile device.

10. The method of claim 9 , wherein the application comprises a mobile banking application, and the service code is linked to the remote telephony service of a payee identified via the mobile banking application.

11. The method of claim 10 , wherein the service code is linked to a transaction identified via the mobile banking application.

12. The method of claim 9 , wherein the application comprises a browser and the service code is linked to a service indicated in the browser.

13. A non-transitory computer program including program code means arranged to perform the method of claim 1 , when executed by a suitably arranged processor or processors.

14. A computer program product comprising the non-transitory computer program of claim 13 .

15. Apparatus arranged to perform the method of claim 1 .

16. A method of user authentication by an application on a mobile telephony device, the method comprising:

i. authenticating the user by interaction with the application,

ii. communicating with a remote authentication service to receive a call identifier;

iii. sending the call identifier within a voice telephone call with the remote telephony service, by means of which the user is authenticated to the remote telephony service;

iv. wherein the remote authentication service links an identity of the user to a user identity code of the remote telephony service, and provides the user identity code to the remote telephony service.

17. The method of claim 16 , wherein the remote telephony service is pre-registered with the authentication service.

18. A non-transitory computer program including program code means arranged to perform the method of claim 16 , when executed by a suitably arranged processor or processors.

19. A computer program product comprising the non-transitory computer program of claim 18 .

20. A method of user authentication by an application on a mobile telephony device, the method comprising:

i. authenticating the user by interaction with the application,

ii. communicating with a remote authentication service to receive a call identifier;

iii. sending the call identifier within a voice telephone call with the remote telephony service, by means of which the user is authenticated to the remote telephony service;

wherein the call identifier is hidden within the voice telephone call by audio steganography.

21. The method of claim 20 , wherein additional information is sent by the application to the remote telephony service within the voice telephone call, the additional information being hidden by audio steganography.

22. The method of claim 21 , wherein the additional information comprises a payment instruction.

23. The method of claim 20 , wherein the audio steganography comprises spread spectrum encoding.

24. The method of claim 20 , wherein the application is pre-registered with the authentication service, to generate one or more cryptographic keys for secure communication between the mobile application and the remote authentication service.

25. The method of claim 24 , wherein identity data associated with the mobile application is stored by the remote authentication service.

26. The method of claim 24 , wherein the one or more cryptographic keys are generated from a passcode entered by the user.

27. A non-transitory computer program including program code means arranged to perform the method of claim 20 , when executed by a suitably arranged processor or processors.

28. A computer program product comprising the non-transitory computer program of claim 27 .

29. A system for user authentication over a telephony channel, the system comprising:

i. a mobile telephony device having an authentication application;

ii. an authentication service arranged for communication with the authentication application; and

iii. a telephony service arranged for telephonic communication with the mobile telephony device;

wherein the application is arranged to authenticate a user, receive a service code, communicate with the authentication service to receive a call identifier based on the service code; and to send the call identifier within a voice telephone call with the telephony service so as to authenticate the user with the remote telephony service.

30. A system for user authentication over a telephony channel, the system comprising:

i. a mobile telephony device having an authentication application;

ii. an authentication service arranged for communication with the authentication application; and

iii. a remote telephony service arranged for telephonic communication with the mobile telephony device;

wherein the application is arranged to authenticate a user, communicate with the authentication service to receive a call identifier; and to send the call identifier within a voice telephone call with the remote telephony service so as to authenticate the user with the remote telephony service; and

wherein the authentication service is arranged to link an identity of the user to a user identity code of the remote telephony service, and to provide the user identity code to the remote telephony service.

31. A system for user authentication over a telephony channel, the system comprising:

i. a mobile telephony device having an authentication application;

ii. an authentication service arranged for communication with the authentication application; and

iii. a remote telephony service arranged for telephonic communication with the mobile telephony device;

wherein the application is arranged to authenticate a user, communicate with the authentication service to receive a call identifier; and to send the call identifier within a voice telephone call with the telephony service so as to authenticate the user with the remote telephony service, the call identifier being hidden within the voice telephone call by audio steganography.