System and method for copy protection for digital signals

• US 8,565,426 B2
• Filed: 10/18/2007
• Issued: 10/22/2013
• Est. Priority Date: 01/08/1998
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Chaney, Jack
• Primary Examiner(s): Shiferaw, Eleni
• Assistant Examiner(s): CALLAHAN, PAUL E
• Application Number:
  US11/874,791
• Publication Number:
  US 20080101603A1
• Time in Patent Office: 2,196 Days
• Field of Search: 380/203, 380/205, 380/210, 380/206, 725/31, 725/26, 726/26, 705/51, 705/57
• US Class Current: 380/203
• 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 20/00855 involving a step of exchanging information with a remote server
• CPC Class Codes: G11B 2020/10537 Audio or video recording
• CPC Class Codes: G11B 23/28 Indicating or preventing prior or unauthorised use, e.g. cassettes with sealing or locking means, write-protect devices for discs write-protect devices for tapes G11B23/042, G11B23/08714; dummy cassettes for locking in the drive G11B33/005
• CPC Class Codes: G11B 23/284 on the record carrier
• 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 21/4181 for conditional access
• CPC Class Codes: H04N 21/4367 Establishing a secure communication between the client and a peripheral device or smart card
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/4408 involving video stream encryption, e.g. re-encrypting a decrypted video stream for redistribution in a home network
• CPC Class Codes: H04N 21/8355 involving usage data, e.g. number of copies or viewings allowed
• CPC Class Codes: H04N 5/913 for scrambling ; for copy protection
• CPC Class Codes: H04N 7/163 by receiver means only
• 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

Embodiments of the present invention provide for the copy protection of distributed material after conditional access is applied, regardless of where the material is distributed. The solutions described provide the advantage of being sufficiently simple in implementation to qualify as “curb high” solutions. “Curb high” solutions provide a range of security from minimal security to a high level of security while requiring relatively fewer system resources to implement than prior approaches.

Claims

1. A method of copy protecting signals flowing from a security module to a receiver via an interface, the method comprising:

(a) receiving a digital signal in the receiver, the digital signal including a combined scrambled and copy protected signal;

(b) transmitting the digital signal from the receiver to a descrambler module of the security module via the-interface;

(c) receiving a combined descrambled and copy protected signal from the descrambler module; and

(d) reconverting the descrambled and copy protected signal to a non-copy protected descrambled signal in the receiver using a copy protection data signal obtained from the receiver,

wherein use of the digital signal is prevented without access to and use of the copy protection data signal at the receiver, and the copy protected signal is prevented from being used for playing audio-visual information without using the copy protection data signal at the receiver to remove the copy protection from the descrambled copy protected signal.

2. The method of claim 1, further comprising generating the copy protection data signal by utilizing a scheme that uses a random number generation in the receiver.

3. The method of claim 2, further comprising applying an inverse function in the receiver using the copy protection data signal to remove the copy protection from the descrambled copy protected signal, and decoding an unprotected signal.

4. The method of claim 2, further comprising descrambling the digital signal and converting the descrambled signal into the descrambled copy protected signal using the copy protection data signal.

5. The method of claim 1, wherein the digital signal in step (a) is encoded and scrambled.

6. The method of claim 1, wherein the security module comprises a PCMCIA card.

7. The method of claim 1, wherein the link comprises one or more communication media configured for carrying digital signals.

8. The method of claim 1, wherein the receiver and the descrambler module utilize IS679 compatible interfaces for communication via the link.

9. The method of claim 1, further comprising decoding the descrambled signal in the receiver after step (d).

10. A method of copy protecting signals flowing from a security module to a receiver via an interface, the method comprising:

(a) receiving a digital signal in the receiver, the digital signal including a scrambled signal;

(b) transmitting the digital signal from the receiver to a descrambler module of the security module via the interface;

(c) receiving a combined descrambled and copy protected signal, which has been descrambled and copy protected using a copy protection data signal obtained from the receiver, from the descrambler module; and

(d) reconverting the combined descrambled and copy protected signal to a descrambled signal in the receiver using the copy protection data signal,

wherein use of the digital signal is prevented without access to the copy protection data signal at the receiver, and the copy protected signal is prevented from being used for playing audio-visual information without using the copy protection data signal to remove the copy protection from the combined descrambled and copy protected signal.

11. The method of claim 10, wherein use of the digital signal is prevented without access to the copy protection data signal obtained from the receiver, and the combined descrambled and copy protected signal can still be copied even without the copy protection data, but that copy cannot be used without the copy protection data signal from the receiver in order to remove the copy protection from the copy.