Method for managing copy protection information of recording medium

• US 20040213113A1
• 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:
  US10/831,172
• Publication Number:
  US 20040213113A1
• Time in Patent Office: Days
• US Class Current: 369/53.21
• CPC Class Codes: G06F 21/1011 to devices
• 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 20/00195 using a device identifier associated with the player or recorder, e.g. serial numbers of playback apparatuses or MAC addresses
• 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 20/00369 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 7/24082 Meandering

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 a drive ID are recorded together in a key locker of the optical disc. When a data stream of an optical disc is reproduced, reading and decryption of the copy protection information is selectively performed depending on whether the drive ID recorded in the key locker and a drive ID managed in an optical disc drive, into which the optical disc is inserted, are identical. This prevents contents such as broadcast programs recorded in an optical disc 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 and recording the data stream in a data area of a recording medium; and

recording a drive ID managed in a drive, which records the data stream, in a first specific area of the recording medium,

wherein said copy protection information is previously recorded in the first specific area, and a hidden code for decrypting the copy protection information is previously recorded in a second specific area of the recording medium.

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 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.

4. The method according to claim 1, wherein the data stream encrypted based on the copy protection information is a digital broadcast data stream that is prohibited from being duplicated.

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

a) comparing a drive ID read from a first specific area of a recording medium with a drive ID managed in a drive for reproducing the recording medium;

b) decrypting copy protection information recorded in the first specific area using a key read from a second specific area of the recording medium if the comparison result at said step a) is that the two drive IDs are identical; and

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

6. The method according to claim 5, wherein if the drive ID managed in the drive and the drive ID read from the recording medium are not identical, the decryption of the copy protection information at said step b) is stopped.

7. The method according to claim 5, wherein the key read from the second specific area is a hidden code recorded in the form of a wobble having a low frequency component that is not duplicated using a bit to bit copy.

8. A recording medium, comprising:

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

a first specific area in which the copy protection information and a unique ID of a drive for recording the data stream in the recording medium are recorded; and

a second specific area in which a hidden code for decrypting the copy protection information in the first specific area is recorded.

9. The medium according to claim 8, wherein the recording medium is a write once optical disc or a rewritable optical disc.

10. The medium according to claim 8, wherein the copy protection information and the hidden code are recorded when the recording medium is manufactured.

11. The medium 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.

12. The medium according to claim 8, wherein the data stream recorded in the data area is a digital broadcast data stream that is prohibited from being duplicated.

13. 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 storage unit for storing a unique ID of the apparatus,

wherein a hidden code for decrypting the copy protection information is recorded in a second specific area of the recording medium, a data stream encrypted using the copy protection information is recorded in a data area of the recording medium, and a unique ID of an apparatus for recording the data stream in the recording medium is additionally recorded in the first specific area.

14. The apparatus according to claim 13, wherein the copy protection information calculation unit includes:

a comparison portion for comparing an apparatus ID read from the first specific area with an apparatus ID stored in the storage unit; and

a decryption portion for decrypting the copy protection information read from the first specific area, using the hidden code read from the second specific area, if the two apparatus IDs are identical.

15. The apparatus according to claim 14, wherein if the apparatus ID read from the first specific area and the apparatus ID stored in the storage unit are not identical, the decryption portion stops the decryption of the copy protection information.

16. The apparatus according to claim 13, wherein the data stream recorded in the data area is a digital broadcast data stream that is prohibited from being duplicated.

17. The apparatus according to claim 13, wherein when a digital broadcast data stream prohibited from being duplicated is recorded in the data area, the unique ID stored in the storage unit is additionally recorded in the first specific area of the recording medium.

18. The apparatus according to claim 13, wherein the recording medium is a write once optical disc or a rewritable optical disc.

19. The apparatus according to claim 13, wherein the copy protection information and the hidden code are recorded when the recording medium is manufactured.