Transferring a data object between devices

• US 20080104706A1
• Filed: 10/31/2006
• Published: 05/01/2008
• Est. Priority Date: 10/31/2006
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Kalker, Antonius A.C.M., Karp, Alan H.
• Granted Patent: US 8,091,137 B2
• Time in Patent Office: Days
• US Class Current: 726/26
• CPC Class Codes: H04L 2209/603 Digital right managament [DRM]
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management data processing systems or methods, specially adapted for commerce, e.g. marketing, shopping, billing, auctions or e-commerce G06Q30/00
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/0825 using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates
• CPC Class Codes: H04L 9/0897 involving additional devices, e.g. trusted platform module [TPM], smartcard or USB
• CPC Class Codes: H04L 9/30 Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy

Abstract

A playable copy of the digital content object is stored at a first device. A data object associated with the digital content object is sent to a second device. The playable copy of the digital content object is disabled at the first device, such that only an authorized, playable copy of the digital content object is operable to be stored on the first and second device at any given time before, during and after sending the data object.

Claims

1. A method of transferring a data object between devices, wherein the data object is associated with controlling a playability of a digital content object, the method comprising:

storing a playable copy of the digital content object at a first device;

sending the data object associated with the digital content object to a second device; and

disabling the playable copy of the digital content object at the first device, such that only an authorized, playable copy of the digital content object is operable to be stored on the first device and the second device at any given time before, during and after sending the data object.

2. The method of claim 1, wherein the data object is an encryption key and disabling the playable copy of the digital content object at the first device comprises:

deleting the encryption key at the first device.

3. The method of claim 2, wherein the encryption key comprises a content key or a locker key.

4. The method of claim 1, wherein disabling the playable copy of the digital content object at the first device comprises deleting at least one of an identification of the stored digital content object and an identification of an encryption key used to play the digital content object.

5. The method of claim 1, wherein the data object comprises the digital content object.

6. The method of claim 1, wherein an authorized, playable copy of the digital content object comprises only a single, authorized copy of the digital content object that is stored on the first device or the second device at any given time.

7. The method of claim 1, further comprising:

privately storing the data object with the assistance of trusted hardware in the first device and the second device.

8. The method of claim 1, wherein storing digital content comprises:

storing the digital content in trusted hardware.

9. The method of claim 8, wherein the trusted hardware comprises a trusted platform module.

10. The method of claim 1, wherein storing digital content comprises:

storing the digital content in memory secured by but external to the trusted hardware.

11. The method of claim 1, wherein the authorized, playable copy of the digital content object comprises multiple authorized copies, the method further comprising:

storing a copy regulation value in the first device indicating a number of playable, authorized copies of the digital content object, n, where n>

1;

sending an indication of a number of playable, authorized copies of the digital content object, m, from the number of copies, n, being transferred to the second device, where m<

n;

updating the copy regulation value in the first device to be equal to n-m.

12. The method of claim 11, further comprising:

storing a copy regulation value in the second device indicating the number of playable, authorized copies of the digital content object, m, transferred to the second device.

13. The method of claim 11, further comprising:

preventing copying of the playable digital content object in the first device if the copy regulation value in the first device reaches zero; and

preventing copying of the playable digital content object in the second device if the copy regulation value in the second device reaches zero.

14. The method of claim 1, further comprising:

receiving the digital content object encrypted with a content key; and

receiving the content key encrypted with an asymmetric or symmetric key known by trusted hardware in the first device.

15. The method of claim 14, wherein sending the data object associated with the digital content object to a second device comprises:

decrypting the content key with the key known by the trusted hardware in the first device; and

encrypting the content key with an asymmetric or symmetric key known by trusted hardware in the second device; and

sending the content key encrypted with the asymmetric or symmetric key known by trusted hardware in the second device to the second device.

16. The method of claim 15, further comprising using a binding key to determine the content key.

17. A device for enforcing a protocol giving digital content a physical transfer property, the device comprising:

a processing circuit enforcing the protocol giving the digital content the physical transfer property, the physical transfer property including having no more than an authorized number of playable copies of the digital content on one of a plurality of devices at any given time, including when the digital content is stored on the device, during a transfer to a second device and after the transfer to the second device; and

storage storing the digital content.

18. The device of claim 17, further comprising:

trusted hardware including the processing circuit, wherein the trusted hardware is tamper resistant and operable to be authenticated; and

the storage including storage external to the trusted hardware storing the digital content as an encrypted digital content object, wherein the trusted hardware is operable to send a data object associated with the encrypted digital content object to the second device for transferring at least one authorized playable copy of the number of authorized playable copies to the second device, and disable access to at least one authorized playable copy at the first device.

19. A computer program embedded on a computer readable storage medium, the computer program including instructions that when executed by a processing circuit implement a method comprising:

enforcing a protocol giving digital content a physical transfer property, the physical transfer property including having no more than an authorized number of playable copies of the digital content on one of a plurality of devices at any given time, including when the digital content is stored on the device, during a transfer to a second device and after the transfer to the second device.

20. The computer program of claim 19, wherein enforcing the protocol comprises:

sending a data object associated with the digital content to the second device to transfer at least one playable copy of the digital content to the second device; and

disabling the at least one transferred playable copy of the digital content at the first device, such that no more than the authorized number of playable copies are stored on the first and second device at any given time.