Signal tracing system and method

• US 7,233,670 B2
• Filed: 02/25/2002
• Issued: 06/19/2007
• Est. Priority Date: 02/26/2001
• Status: Expired due to Fees

• Current Assignee: Nagravision SA (Kudelski SA)
• Original Assignee: Nagravision SA (Kudelski SA)
• Inventors: Goeke, Maxime
• Primary Examiner(s): Barron, Gilberto
• Assistant Examiner(s): PERUNGAVOOR, VENKATANARAY
• Application Number:
  US10/469,039
• Publication Number:
  US 20040076297A1
• Time in Patent Office: 1,940 Days
• Field of Search: 380/209, 380/241, 380/226
• US Class Current: 380/241
• CPC Class Codes: H04H 20/103 Transmitter-side switching
• CPC Class Codes: H04H 60/23 using cryptography, e.g. encryption, authentication, key distribution
• CPC Class Codes: H04N 21/222 Secondary servers, e.g. proxy server, cable television Head-end provisioning of proxy services in data packet switching networks H04L67/56
• CPC Class Codes: H04N 21/2343 involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements video transcoding H04N19/40; media packet handling at the source H04L65/762
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/8358 involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467
• CPC Class Codes: H04N 7/165 Centralised control of user terminal subsequent to an upstream request signal H04N7/17345; Registering at central by two-way working H04N7/17309

Abstract

A system and a method are for determining the origin of a signal received by a pay television subscriber in a given region. A system includes an encryption device located at a main operator, a transmission device adapted to transmit an encrypted video signal towards at least one local operator, and a decryption device at the local operator. The decryption device includes an identification device for replacing all or part of the decrypted video signal with an identification signal characterising the decryption device.

Claims

1. System for identifying an origin of a signal broadcasted to a subscriber, comprising:

an encryption device located at a main operator;

a transmission device, adapted to transmit an encrypted video signal towards at least one local operator; and

a decryption device located at the at least one local operator, adapted to provide the local operator with a decrypted signal for broadcasting to subscribers, wherein the decryption device includes a substitution device, adapted to replace at least part of the decrypted video signal with an identification signal characterising the decryption device.

2. System for identifying the origin of signal according to claim 1, wherein the decryption device includes a decryption module and a security module.

3. System for identifying the origin of a signal according to claim 2, wherein the identification signal includes an identifier of the decryption module and an identifier of the security module.

4. System for identifying the origin of a signal according to claim 1, wherein the identification signal is placed in a randomly defined area on a screen.

5. System for identifying the origin of a signal according to claim 1, wherein the identification signal is overlaying a current image such as a background.

19. An apparatus according to claim 1, wherein the identification signal is overlaying the current image such as a background.

6. Method for identifying the origin of a signal broadcasted to a subscriber, the method comprising:

encrypting a video signal by a main operator;

transmitting the encrypted signal to several local operators;

decrypting the encrypted signal by a decryption module of an enabled local operator and disposing of the decrypted signal; and

,

broadcasting of the decrypted signal to subscribers of said local operator,

wherein;

at least part of the decrypted signal is substituted with an identification signal identifying the decryption module prior to broadcasting.

7. Method according to claim 6, wherein the identification signal replaces a part of an image formed by the decrypted signal in any region of the image.

8. Method according to claim 6, wherein the identification signal is overlaying a current image such as a background.

9. A method according to claim 6, wherein an identification command by the main operator is to at least one decryption module.

10. System for identifying an origin of a signal broadcasted to a subscriber, comprising:

transmission means for transmitting an encrypted video signal towards at least one local operator; and

decryption means, located at the at least one local operator, for providing the local operator with a decrypted signal for broadcasting to subscribers, wherein the decryption means includes substitution means for replacing at least part of the decrypted video signal with an identification signal characterising the decryption means.

11. System for identifying the origin of a signal according to claim 10, wherein the decryption means includes a decryption module and a security module.

12. System for identifying the origin of a signal according to claim 11, wherein the identification signal includes an identifier of the decryption module and an identifier of the security module.

13. System for identifying the origin of a signal according to claim 10, wherein the identification signal is placed in a randomly defined area on a screen.

14. System for identifying the origin of a signal according to claim 10, wherein the identification signal is overlaying a current image such as a background.

15. An apparatus, comprising:

a decryption device associated with a local operator, adapted to decrypt a previously encrypted video signal transmitted toward the local operator, to produce a decrypted signal for broadcasting to subscribers, wherein the decryption device includes a substitution device, adapted to replace at least part of the decrypted video signal with an identification signal characterising the decryption device.

16. An apparatus according to claim 15, wherein the decryption device includes a decryption module and a security module.

17. An apparatus according to claim 16, wherein the identification signal includes an identifier of the decryption module and an identifier of the security module.

18. An apparatus according to claim 15, wherein the identification signal is placed in a randomly defined area on a screen.

20. A method, comprising:

decrypting a received previously encrypted signal using a decryption module associated with an enabled local operator; and

broadcasting the decrypted signal to at least one subscriber of the local operator, wherein at least part of the decrypted signal is substituted with an identification signal identifying the decryption module prior to broadcasting.

21. A method according to claim 20, wherein the identification signal replaces a part of the image formed by the decrypted signal in any region of the image.

22. A method according to claim 20, wherein the identification signal is overlaying the current image such as a background.

23. A method according to claim 20, wherein an identification command by a main operator is to at lest one decryption module.