Multi-level, multi-dimensional content protections

• US 20030002668A1
• Filed: 06/30/2001
• Published: 01/02/2003
• Est. Priority Date: 06/30/2001
• Status: Abandoned Application

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Ripley, Michael S., Brickell, Ernie, Graunke, Gary
• Application Number:
  US09/896,537
• Publication Number:
  US 20030002668A1
• Time in Patent Office: Days
• US Class Current: 380/45
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 2221/2113 Multi-level security, e.g. mandatory access control
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00731 involving a digital rights management system for enforcing a usage restriction
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management
• CPC Class Codes: H04L 63/04 for providing a confidential data exchange among entities communicating through data packet networks
• CPC Class Codes: H04L 63/105 Multiple levels of security
• CPC Class Codes: H04L 9/0836 using tree structure or hierarchical structure
• CPC Class Codes: H04N 2005/91364 the video signal being scrambled
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/26613 for generating or managing keys in general key distribution for secret or secure communication involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP] H04L9/083; network support of key management H04L63/06; key management for network security in communication control or processing H04W12/04
• CPC Class Codes: H04N 5/913 for scrambling ; for copy protection
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

In one aspect of the invention is a method for a multi-level, and multi-dimensional scheme of content protection. Content having one or more attributes is encrypted using separate keys for each level of protection, where each level corresponds to an assurance of protection for each attribute. The content may be distributed to a number of environments having different levels of protection by transmitting a base key commensurate with the environment'"'"'s subscription level. The base key may then be used generate lower level keys for accessing content at a level of protection less than or equal to that subscribed to.

Claims

1. A method comprising:

receiving content comprising a set of attributes having L through N levels of access, where L<

N, and content at a given level of access being decryptable by a corresponding key;

receiving a base key corresponding to an M of N level of access, where LMN; and

deriving lower level keys based on the base key, the lower level keys being used to access content having an M level of access or lower.

2. The method of claim 1, additionally comprising receiving a D-dimensional matrix for each attribute in the set of attributes, wherein D corresponds to a number of attributes of the content, and wherein the matrix comprises matrix values for determining how to generate a key corresponding to a given section of the content, and said deriving lower level keys based on the base key comprises, for a given lower level key, using a function based on a matrix value corresponding to the lower level key and a one-way hash function of an adjacent higher level key.

3. The method of claim 1, wherein said deriving lower level keys based on the base key comprises, for a given lower level key, using a modular exponentiation of a higher level key.

4. A method comprising:

receiving a request for content at an M level of access, the content comprising a set of attributes having L through N levels of access, where L<

N, and each level of access being represented by a grid point on a grid, and corresponding content being decryptable by a key corresponding to the level of access;

transmitting a base key corresponding to the M level of access; and

transmitting a D-dimensional matrix for each attribute in the set of attributes, where D corresponds to a number of attributes of the content, and where the matrix comprises matrix values for determining how to generate a lower level key for decrypting content represented by a given grid point on the grid.

5. The method of claim 4, wherein a given lower level key in a 2 dimensional matrix, where X comprises a first matrix, and Y comprises a second matrix, is generated by at least one of:

the equation K_i,j=X_i,jH(K_i+1,j); and

the equation K_i,j=Y_i,jH(K_i,j+1),

where X_i,j and Y_i,j each comprises a matrix value corresponding to content attributes at a level of access represented by a grid point (i, j), and H(K_i+1,j) and H(K_i,j+1) each comprise a one-way hash value of a higher level key.

6. The method of claim 4, wherein a given lower level key in a 1 dimensional matrix represented by X is generated by the equation K_i=H(K_i+1).

7. A method comprising:

creating a hierarchy of keys, where each key is used to encrypt content having a set of attributes, and having one or more levels of access, and each key corresponds to a level of access; and

applying each of the keys to the content to create a plurality of sections of encrypted content, each section being a portion of the content, and each successive section of the content improving the set of attributes of the content.

8. The method of claim 7, additionally comprising creating a D-dimensional matrix for each attribute in the set of attributes, wherein D corresponds to a number of attributes of the content, and wherein the matrix comprises matrix values for determining how to generate a key corresponding to a given section of the content.

9. The method of claim 7, wherein the hierarchy of keys are related by a cryptographic strength one-way function.

10. The method of claim 7, wherein an attribute comprises resolution.

11. A machine-readable medium having stored thereon data representing sequences of instructions, the sequences of instructions which, when executed by a processor, cause the processor to perform the following:

receive content comprising a set of attributes having L through N levels of access, where L<

N, and content at a given level of access being decryptable by a corresponding key;

receive a base key corresponding to an M of N level of access, where LMN; and

derive lower level keys based on the base key, the lower level keys being used to access content having an M level of access of lower.

12. The method of claim 11, additionally comprising instructions that cause the processor to receive a D-dimensional matrix for each attribute in the set of attributes, wherein D corresponds to a number of attributes of the content, and wherein the matrix comprises matrix values for determining how to generate a key corresponding to a given section of the content, and the instructions cause the processor to derive lower level keys based on the base key comprises, for a given lower level key, using a function based on a matrix value corresponding to the lower level key and a one-way function of an adjacent higher level key.

13. The method of claim 11, wherein the instructions cause the processor to derive lower level keys based on the base key comprises, for a given lower level key, by using a modular exponentiation of a higher level key.

15. The method of claim 14, additionally comprising instructions that cause the processor to receive a D-dimensional matrix for each attribute in the set of attributes, wherein D corresponds to a number of attributes of the content, and wherein the matrix comprises matrix values for determining how to generate a key corresponding to a given section of the content, and the instructions cause the processor to derive lower level keys based on the base key comprises, for a given lower level key, using a function based on a matrix value corresponding to the lower level key and a one-way hash function of an adjacent higher level key.

16. The method of claim 14, wherein the instructions cause the processor to derive lower level keys based on the base key comprises, for a given lower level key, by using a modular exponentiation of a higher level key.

18. The method of claim 17, additionally comprising means to receive a D-dimensional matrix for each attribute in the set of attributes, wherein D corresponds to a number of attributes of the content, and wherein the matrix comprises matrix values for determining how to generate a key corresponding to a given section of the content, and the means to derive lower level keys based on the base key comprises, for a given lower level key, using a function based on a matrix value corresponding to the lower level key and a one-way hash function of an adjacent higher level key.

19. The method of claim 17, wherein the means to derive lower level keys based on the base key comprises, for a given lower level key, using a modular exponentiation of a higher level key.

14. An apparatus comprising:

at least one processor; and

a machine-readable medium having instructions encoded thereon, which when executed by the processor, are capable of directing the processor to;

receive content comprising a set of attributes having L through N levels of access, where L<

N, and content at a given level of access being decryptable by a corresponding key;

receive a base key corresponding to an M of N level of access, where LMN; and

derive lower level keys based on the base key, the lower level keys being used to access content having an M level of access of lower.

17. An apparatus comprising:

means to receive content comprising a set of attributes having L through N levels of access, where L<

N, and content at a given level of access being decryptable by a corresponding key;

means to receive a base key corresponding to an M of N level of access, where LMN; and

means to derive lower level keys based on the base key, the lower level keys being used to access content having an M level of access of lower.

20. A method comprising:

receiving encrypted content comprising a set of attributes having L through N levels of access, where L<

N, and each level being accessible by a corresponding key;

receiving a base key corresponding to an M of N level of access, where LMN;

deriving lower level keys based on the base key, the lower level keys being used to access content having an M level of access or lower; and

using a given lower level key to decrypt the content at a corresponding level.

21. The method of claim 20, additionally comprising receiving a D-dimensional matrix for each attribute in the set of attributes, wherein D corresponds to a number of attributes of the content, and wherein the matrix comprises matrix values for determining how to generate a key corresponding to a given section of the content, and said deriving lower level keys based on the base key comprises, for a given lower level key, using a function based on a matrix value corresponding to the lower level key and a one-way function of an adjacent higher level key.

22. The method of claim 20, wherein said deriving lower level keys based on the base key comprises, for a given lower level key, using a modular exponentiation of a higher level key.