Method for managing copy protection information of recording medium

• US 20040213408A1
• Filed: 04/26/2004
• Published: 10/28/2004
• Est. Priority Date: 04/24/2003
• Status: Abandoned Application

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Stechkine, Alexandre, Kim, Byung Jin, Kim, Hyung Sun
• Application Number:
  US10/831,197
• Publication Number:
  US 20040213408A1
• Time in Patent Office: Days
• US Class Current: 380/200
• 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 20/00304 the key being stored in the lead-in area [LIA]
• CPC Class Codes: G11B 20/00326 the key being embossed on the record carrier
• CPC Class Codes: G11B 20/00333 the key being stored in header data, e.g. in sector headers
• CPC Class Codes: G11B 20/00369 wherein a first key, which is usually stored on a hidden channel, e.g. in the lead-in of a BD-R, unlocks a key locker containing a second
• CPC Class Codes: G11B 20/00405 the key being stored by varying characteristics of the recording track, e.g. by altering the track pitch or by modulating the wobble track
• CPC Class Codes: G11B 20/00514 wherein the entire content is encrypted with the same key, e.g. disc key or master key
• CPC Class Codes: G11B 20/00731 involving a digital rights management system for enforcing a usage restriction
• CPC Class Codes: G11B 20/00753 wherein the usage restriction limits the number of copies that can be made, e.g. CGMS, SCMS, or CCI flags
• CPC Class Codes: G11B 20/0084 wherein the usage restriction can be expressed as a specific time or date
• CPC Class Codes: G11B 20/00869 wherein the remote server can deliver the content to a receiving device
• CPC Class Codes: G11B 2020/10537 Audio or video recording
• CPC Class Codes: G11B 2220/2541 Blu-ray discs; Blue laser DVR discs
• CPC Class Codes: H04N 2005/91364 the video signal being scrambled
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/44204 Monitoring of content usage, e.g. the number of times a movie has been viewed, copied or the amount which has been watched monitoring of user activities for profile generation for accessing a video database G06F16/739; protecting generic digital content where the protection is independent of the precise nature of the content G06F21/10; arrangements for monitoring the use made of the broadcast services in broadcast systems H04H60/31
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/8355 involving usage data, e.g. number of copies or viewings allowed
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection

Abstract

A method for managing copy protection information of a recording medium is disclosed. A data stream encrypted using copy protection information is recorded in a data area of an optical disc such as a write once optical disc or a rewritable optical disc, while the copy protection information and Digital Rights Management (DRM) information set by a content provider are recorded together in a key locker of the optical disc. When a data stream of an optical disc is reproduced, the operation of reproducing or copying the encrypted data stream is controlled according to information of allowed playback time, the number of copy times and copy permission/prohibition information, which is included in the Digital Rights Management information. This effectively prevents contents such as data files transmitted over the Internet from being illegally duplicated.

Claims

1. A method for managing copy protection information of a recording medium, the method comprising:

encrypting a data stream based on copy protection information recorded in a first specific area of a recording medium, and recording the encrypted data stream in a data area of the recording medium; and

recording Digital Rights Management information for the data stream in the first specific area.

2. The method according to claim 1, wherein the recording medium is a write once optical disc or a rewritable optical disc.

3. The method according to claim 1, wherein the Digital Rights Management information is used to control copying or playback of the data stream.

4. The method according to claim 3, wherein the Digital Rights Management information includes an allowed playback time of the data stream, the number of copy times thereof, and information as to whether copying thereof is allowed or not.

5. The method according to claim 1, wherein the data stream is a data file received over a network.

6. The method according to claim 5, wherein the Digital Rights Management information is read from header information of the data file.

7. The method according to claim 5, wherein the Digital Rights Management information is recorded while being divided according to data files.

8. The method according to claim 1, wherein a hidden code for decrypting the copy protection information and the Digital Rights Management information is recorded in a second specific area of the recording medium.

9. The method according to claim 8, wherein the hidden code is recorded in the form of a wobble having a low frequency component that is not duplicated using a bit to bit copy.

10. A method for managing copy protection information of a recording medium, the method comprising the steps of:

a) confirming Digital Rights Management information recorded in a first specific area of a recording medium; and

b) decrypting the copy protection information recorded in the first specific area according to the confirmed Digital Rights Management information; and

c) decrypting a data stream, encrypted and recorded in a data area of the recording medium, using the decrypted copy protection information.

11. The method according to claim 10, wherein the Digital Rights Management information is used to control copying or playback of the data stream.

12. The method according to claim 11, wherein the Digital Rights Management information is managed while being divided according to data files corresponding to the data stream.

13. The method according to claim 12, wherein the copy protection information is decrypted only if information of a data file to be reproduced or copied, said information being included in the confirmed Digital Rights Management information, satisfies a playback or copying condition of the data file.

14. The method according to claim 12, further comprising the step of, if playback or copying of a data file is performed, updating information regarding the performed playback or copying, included in Digital Rights Management information of the data file, and recording the updated information in the first specific area, overwriting with the updated information.

15. The method according to claim 10, wherein the copy protection information and the Digital Rights Management information are decrypted using a hidden code recorded in a second specific area of the recording medium, said hidden code being recorded in the form of a wobble having a low frequency component that is not duplicated using a bit to bit copy.

16. A recording medium, comprising:

a data area in which a data stream encrypted using copy protection information is recorded; and

a first specific area in which the copy protection information and Digital Rights Management information of the data stream are recorded.

17. The medium according to claim 16, wherein the recording medium is a write once optical disc or a rewritable optical disc.

18. The medium according to claim 16, wherein the Digital Rights Management information is used to control copying or playback of the data stream.

19. The medium according to claim 16, wherein the Digital Rights Management information is recorded while being divided according to data files corresponding to the data stream.

20. The medium according to claim 16, further comprising a second specific area in which a hidden code for decrypting the copy protection information and the Digital Rights Management information is recorded.

21. The medium according to claim 20, wherein the copy protection information and the hidden code are recorded in the recording medium when the recording medium is manufactured.

22. The medium according to claim 20, wherein the hidden code is recorded in the form of a wobble having a low frequency component that is not duplicated using a bit to bit copy.

23. An apparatus for recording and reproducing data in a recording medium, the apparatus comprising:

a pickup unit for recording data in the recording medium or reading data from the recording medium;

a copy protection information calculation unit for decrypting copy protection information encrypted and recorded in a first specific area of the recording medium;

a data processing unit for decrypting data read from the recording medium or encrypting data to be recorded in the recording medium, using the copy protection information; and

a Digital Rights Management information module for analyzing and updating Digital Rights Management information of the data, and controlling the decryption of the copy protection information, based on the Digital Rights Management information,

wherein a data stream encrypted using the copy protection information is recorded in a data area of the recording medium, and Digital Rights Management information of the data stream is recorded in the first specific area.

24. The apparatus according to claim 23, wherein the Digital Rights Management information is used to control copying or playback of the data stream.

25. The apparatus according to claim 24, wherein the Digital Rights Management information is recorded while being divided according to data files corresponding to the data stream.

26. The apparatus according to claim 23, wherein when a data stream containing Digital Rights Management information is encrypted and recorded in the data area, the Digital Rights Management information module separates the Digital Rights Management information from the data stream and updates the Digital Rights Management information, and the pickup unit additionally records the updated Digital Rights Management information in the first specific area of the recording medium.

27. The apparatus according to claim 26, wherein the data stream containing the Digital Rights Management information is a data file received over a network, and the Digital Rights Management information is read from header information of the data file.

28. The apparatus according to claim 23, wherein when a data file corresponding to the data stream recorded in the recording medium is reproduced or copied, the pickup unit reads Digital Rights Management information of the data file from the first specific area;

the Digital Rights Management information module analyzes the read Digital Rights Management information to confirm whether a playback or copying condition of the data file is satisfied;

the copy protection information calculation unit decrypts copy protection information only if the playback or copying condition of the data file is satisfied; and

the data processing unit decrypts the data stream read from the data area of the recording medium using the decrypted copy protection information.

29. The apparatus according to claim 28, wherein when playback or copying of a data file is performed, the Digital Rights Management information module updates information regarding the performed playback or copying, included in Digital Rights Management information of the data file, and the pickup unit records the updated information in the first specific area, overwriting with the updated information.

30. The apparatus according to claim 23, wherein the copy protection information calculation unit decrypts the copy protection information and the Digital Rights Management information using a hidden code recorded in a second specific area of the recording medium, said hidden code being recorded in the form of a wobble having a low frequency component that is not duplicated using a bit to bit copy.