Contents recording method, recording medium and contents recording device

• US 20050038997A1
• Filed: 07/16/2004
• Published: 02/17/2005
• Est. Priority Date: 07/18/2003
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kato, Taku, Ishihara, Atsushi, Kojima, Tadashi
• Application Number:
  US10/892,554
• Publication Number:
  US 20050038997A1
• Time in Patent Office: Days
• US Class Current: 713/165
• 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 20/00115 wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00246 wherein the key is obtained from a local device, e.g. device key initially stored by the player or by the recorder
• CPC Class Codes: G11B 20/00347 wherein the medium identifier is used as a key
• CPC Class Codes: G11B 20/00362 the key being obtained from a media key block [MKB]
• CPC Class Codes: G11B 20/00434 content protection for pre-recorded media [CPPM]
• CPC Class Codes: G11B 20/00442 content protection for recordable media [CPRM]
• CPC Class Codes: G11B 20/00449 content scrambling system [CSS]
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/0833 involving conference or group key network architectures or network communication protocols for key management in group communication in a packet data network H04L63/065

Abstract

A content recording method comprises encrypting a first key by second keys to generate a first encrypted encryption key group, encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group, encrypting the media identification codes by the first key for each medium to generate encrypted media identification codes, and recording an encrypted content, the content encryption key, the first encrypted encryption key group, the second encrypted encryption key group, and the encrypted media identification codes in a medium.

Claims

1. A recording medium comprising:

a first encrypted encryption key group generated by encrypting a first key by second keys, and a second encrypted encryption key group generated by encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes which are recorded in a lead-in area by embossed pits; and

encrypted media identification codes generated from a group of media identification codes by individually encrypting the codes by the first key for each medium which are recorded in a specific area by a method which inhibits rewriting.

2. A recording medium comprising:

a first encrypted encryption key group generated by encrypting a first key by second keys, and a second encrypted encryption key group generated by decrypting encrypted media identification codes by a media key to extract media identification codes, and encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes which are recorded in a lead-in area by embossed pits; and

encrypted media identification codes generated from a group of media identification codes by individually encrypting the codes by the first key for each medium which are recorded in a specific area by a method which inhibits rewriting.

3. A device for recording a content, comprising:

means for encrypting a first key by second keys to generate a first encrypted encryption key group;

means for encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group;

means for encrypting the media identification codes by the first key for each medium to generate encrypted media identification codes; and

means for recording an encrypted content, the content encryption key, the first encrypted encryption key group, the second encrypted encryption key group, and the encrypted media identification codes in a medium.

4. A device for recording a content, comprising:

means for encrypting a first key by second keys to generate a first encrypted encryption key group;

means for decrypting encrypted media identification codes by a media key to extract media identification codes, and encrypting a content encryption key or third key used as an encryption key of the content encryption key by the media identification codes to generate a second encrypted encryption key group; and

means for recording an encrypted content, the content encryption key, the first encrypted encryption key group, the second encrypted encryption key group, and the media identification codes in a medium.

5. A device for recording an encrypted content in a recording medium wherein:

a first encrypted encryption key group generated by encrypting a first key by second keys, and a second encrypted encryption key group generated by encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes are recorded in a lead-in area of the recording medium by embossed pits; and

encrypted media identification codes generated from a group of media identification codes by individually encrypting the codes by the first key for each medium are recorded in a specific area of the recording medium by a method which inhibits rewriting, the device comprising;

means for reading the first encrypted encryption key group from the recording medium, and extracting the first key by using a device key which encrypts the content;

means for reading the encrypted media identification codes from the recording medium, and decrypting the codes by the first key to generate media identification codes;

means for reading the second encrypted encryption key group from the recording medium, and extracting the third key by using the media identification codes; and

means for encrypting a content by a title key, encrypting the title key by the third key, and recording the encrypted content and the encrypted title key in the recording medium.

6. A device for recording an encrypted content in a recording medium wherein:

a first encrypted encryption key group generated by encrypting a first key by second keys, and a second encrypted encryption key group generated by encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes are recorded in a lead-in area of the recording medium by embossed pits; and

encrypted media identification codes generated from a group of media identification codes by individually encrypting the codes by the first key for each medium are recorded in a specific area of the recording medium by a method which inhibits rewriting, the device comprising;

means for reading the first encrypted encryption key group from the recording medium, and extracting the first key by using a device key which encrypts the content;

means for reading the encrypted media identification codes from the recording medium, and decrypting the codes by the first key to generate media identification codes;

means for reading the second encrypted encryption key group from the recording medium, and extracting the third key by using media identification codes; and

means for encrypting the content by a title key, encrypting the title key by the third key, encrypting the encrypted title key by a secret key, encrypting the secret key by the first key, and recording the encrypted content, a multiencrypted title key, and the encrypted secret key in the recording medium.

7. A method for recording a content, comprising:

encrypting a first key by second keys to generate a first encrypted encryption key group;

encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group;

encrypting the media identification codes by the first key for each medium to generate encrypted media identification codes; and

recording an encrypted content, the content encryption key, the first encrypted encryption key group, the second encrypted encryption key group, and the encrypted media identification codes in a medium.

8. The method according to claim 7, wherein the second keys comprise unique device keys which are distributed to a recording/reproducing device as a key set in which a plurality of keys are set.

9. The method according to claim 7, wherein the encrypted media identification codes are recorded in a specific area of the medium in a postprocess after the encrypted content, the content encryption key, and the first and second encrypted encryption key groups are recorded.

10. The method according to claim 7, wherein each of the encrypted media identification codes comprises a combination of a random number and a serial number.

11. The method according to claim 7, wherein the medium comprises a read-only medium.

12. A method for recording a content, comprising:

encrypting a first key by second keys to generate a first encrypted encryption key group;

encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group;

encrypting the media identification codes and position information in a group of the media identification codes by the first key for each medium to generate encrypted media identification codes; and

recording an encrypted content, the content encryption key, the first encrypted encryption key group, the second encrypted encryption key group, and the encrypted media identification codes in a medium.

13. The method according to claim 12, wherein the second keys comprise unique device keys which are distributed to a recording/reproducing device as a key set in which a plurality of keys are set.

14. The method according to claim 12, wherein the encrypted media identification codes are recorded in a specific area of the medium in a postprocess after the encrypted content, the content encryption key, and the first and second encrypted encryption key groups are recorded.

15. The method according to claim 12, wherein each of the encrypted media identification codes comprises a combination of a random number and a serial number.

16. The method according to claim 12, wherein the medium comprises a read-only medium.

17. A method for recording a content, comprising:

encrypting a first key by second keys to generate a first encrypted encryption key group;

decrypting encrypted media identification codes by a media key to extract media identification codes, and encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group; and

recording an encrypted content, the content encryption key, the first encrypted encryption key group, the second encrypted encryption key group, and the media identification codes in a medium.

18. The method according to claim 17, wherein the second keys comprise unique device keys which are distributed to a recording/reproducing device as a key set in which a plurality of keys are set.

19. The method according to claim 17, wherein the encrypted media identification codes are recorded in a specific area of the medium in a postprocess after the encrypted content, the content encryption key, and the first and second encrypted encryption key groups are recorded.

20. The method according to claim 17, wherein each of the encrypted media identification codes comprises a combination of a random number and a serial number.

21. The method according to claim 17, wherein the medium comprises a read-only medium.

22. A method for recording a content, comprising:

encrypting a first key by second keys to generate a first encrypted encryption key group;

encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group;

encrypting the media identification codes by the first key for each medium to generate encrypted media identification codes;

encrypting a title key which encrypts the content by a media unique key to generate an encrypted title key;

encrypting the content by the title key to generate an encrypted content; and

recording the first encrypted encryption key group, the second encrypted encryption key group, the encrypted media identification codes, the encrypted title key, and the encrypted content in a medium.

23. The method according to claim 22, wherein the second keys comprise unique device keys which are distributed to a recording/reproducing device as a key set in which a plurality of keys are set.

24. The method according to claim 22, wherein the encrypted media identification codes are recorded in a specific area of the medium in a postprocess after the encrypted content, the content encryption key, and the first and second encrypted encryption key groups are recorded.

25. The method according to claim 22, wherein each of the encrypted media identification codes comprises a combination of a random number and a serial number.

26. The method according to claim 22, wherein the medium comprises a read-only medium.

27. A method for recording a content, comprising:

encrypting a first key by second keys to generate a first encrypted encryption key group;

encrypting a content encryption key or third key used as an encryption key of the content encryption key by media identification codes to generate a second encrypted encryption key group;

encrypting the media identification codes by the first key for each medium to generate encrypted media identification codes;

encrypting a title key which encrypts the content by a media unique key to generate an encrypted title key;

encrypting the encrypted title key by a secret key to generate a multiencrypted title key;

encrypting the secret key by a media key to generate an encrypted secret key;

encrypting the content by the title key to generate an encrypted content; and

recording the first encrypted encryption key group, the second encrypted encryption key group, the encrypted media identification codes, the encrypted title key, the multiencrypted title key, the encrypted secret key, and the encrypted content in a medium.

28. The method according to claim 27, wherein the second keys comprise unique device keys which are distributed to a recording/reproducing device as a key set in which a plurality of keys are set.

29. The method according to claim 27, wherein the encrypted media identification codes are recorded in a specific area of the medium in a postprocess after the encrypted content, the content encryption key, and the first and second encrypted encryption key groups are recorded.

30. The method according to claim 27, wherein each of the encrypted media identification codes comprises a combination of a random number and a serial number.

31. The method according to claim 27, wherein the medium comprises a read-only medium.