Communications device authentication

1. A method of accessing a resource requiring identity authentication, the method comprising:

receiving at a communications device an encrypted token in response to an identity of the communications device being authenticated over a first radio access technology;

decrypting the encrypted token using the identity of the communications device; and

using the decrypted token over a second radio access technology to authenticate the identity of the communications device so as to allow access to the resource via the second radio access technology,

wherein the identity of the communications device is not automatically authenticated over the second radio access technology in response to a communication initiated by the communications device over the second radio access technology.

2. The method of claim 1 , wherein the encrypted token is received at the communications device via the first radio access technology.

3. The method of claim 1 , wherein the identity of the communications device is authenticated over the first radio access technology in response to a communication initiated by the communications device over the first radio access technology.

4. The method of claim 1 , wherein the identity of the communications device is authenticated by a first network access point for accessing the resource via a network to which the communications device is registered, and wherein the identity of the communications device is authenticated by a second network access point for accessing the resource via a Wi-Fi network.

5. The method of claim 1 , wherein the first radio access technology is used for accessing the resource via a secure network, and wherein the second radio access technology is used for accessing the resource via a non-secure network.

6. The method of claim 1 , wherein, in response to the identity of the communications device being authenticated over the first radio access technology, the method further comprises:

receiving at the communications device a key generator configured to generate a unique key;

transmitting from the communications device a first key generated using the key generator; and

receiving at the communications device the encrypted token if the first key matches a second key generated using a stored copy of the key generator.

7. The method of claim 6 , wherein the first and second keys, and the key generator, are communicated via the first radio access technology.

8. The method of claim 6 , wherein the copy of the key generator is stored on a backend server.

9. The method of claim 6 , further comprising transmitting identification information from the communications device, and wherein the stored copy of the key generator is retrieved using the transmitted identification information.

10. The method of claim 1 , wherein decrypting the encrypted token comprises:

transmitting from the communications device a first resource token and an ID code, wherein the first resource token is generated using the encrypted token;

receiving at the communications device a second resource token generated using a stored copy of the encrypted token, wherein the stored copy of the encrypted token is retrieved using the transmitted ID code; and

decrypting the encrypted token if the first resource token matches the second resource token.

11. The method of claim 10 , wherein the copy of the encrypted token is stored on a backend server.

12. The method of claim 1 , wherein the identity of the communications device comprises one or more of: the MSISDN, the IMSI, and the model number.

13. A communications device for accessing a resource requiring identity authentication, comprising:

a receiver configured to receive an encrypted token in response to an identity of the communications device being authenticated over a first radio access technology;

a decrypter configured to decrypt the encrypted token using the identity of the communications device; and

transmitter configured to use the decrypted token in a transmission over a second radio access technology to authenticate the identity of the communications device so as to allow access to a resource via the second radio access technology,

wherein the identity of the communications device is not automatically authenticated over the second radio access technology in response to a communication initiated by the communications device over the second radio access technology.

14. A non-transitory computer-readable storage medium comprising computer-executable instructions stored thereon which, when executed on a computer, are configured to carry out the method of claim 1 .