Method and apparatus for distributed conditional access control on a serial communication network

• US 6,154,206 A
• Filed: 01/14/1999
• Issued: 11/28/2000
• Est. Priority Date: 05/06/1998
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation Of America (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Ludtke, Harold Aaron
• Primary Examiner(s): Kostak, Victor R.
• Application Number:
  US09/232,019
• Time in Patent Office: 684 Days
• Field of Search: 348/10, 348/11, 348/12, 348/13, 348/5.5, 455/4.2, 455/5.1, 455/6.1, 455/6.2, 455/6.3, 345/327, 380/10, 380/20, 709/217, 709/218
• US Class Current: 713/168
• CPC Class Codes: H04L 12/2805 Home Audio Video Interoperability [HAVI] networks
• CPC Class Codes: H04L 12/2838 Distribution of signals within a home automation network, e.g. involving splitting/multiplexing signals to/from different paths adaptations of television systems for transmission by electric cable for domestic distribution H04N7/106; hybrid transport H04L12/6418; home network arrangements specially adapted for distribution of digital video signals H04N7/24
• CPC Class Codes: H04L 12/40104 Security; Encryption; Content protection cryptographic protocols H04L9/00; protocols for network security H04L63/00
• CPC Class Codes: H04L 12/40117 Interconnection of audio or video/imaging devices home automation networks H04L12/2803; bitstream network arrangements specially adapted for distribution of digital video signals H04N7/24
• CPC Class Codes: H04N 21/43607 Interfacing a plurality of external cards, e.g. through a DVB Common Interface [DVB-CI]
• 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

A method and apparatus for distributed conditional access (CA) control on a serial communication network. An exemplary embodiment of the present invention includes a CA subsystem over a 1394 network, the CA subsystem comprising a receiver unit for receiving a digital broadcast signal (DBS) and OOB data from an external source, where the DBS and OOB data are transmitted from the external source to the receiver unit in different broadcast frequencies. The receiver unit comprises a main tuner subunit coupled to receive the DBS, which can be encrypted with respect to a first encryption scheme. The receiver unit also comprises an OOB tuner subunit coupled to receive the OOB data for decrypting the DBS with respect to the first encryption scheme. The CA subsystem also comprises a CA control unit coupled to the receiver unit, which in turn comprises a CA subunit coupled to receive the DBS and OOB data. If the DBS is encrypted with respect to the first encryption scheme, the CA subunit generates a descrambled signal from the DBS using the OOB data, such that said descrambled signal is no longer encrypted with respect to the first encryption scheme. Other embodiments of the present invention include the above and wherein the descrambled signal is encrypted with respect to a standard 1394 copy protection scheme, but not encrypted with respect to the first encryption scheme.

Claims

1. A communication network comprising:

a) a receiver unit configured to receive information from a service provider and coupled to a serial communication network, said receiver unit comprising;

a1) a first tuner configured to generate a first digital signal encoded under a first encryption format;

a2) a second tuner configured to generate out-of-band (OOB) data, wherein said first digital signal and said OOB data are transmitted on said serial communication network; and

b) a first conditional access (CA) unit coupled to said serial communication network configured to receive said first digital signal and said OOB data, said first CA unit configured to generate a first decrypted digital signal (DDS) based on said OOB data and said first encryption format, said first CA unit also configured to transmit said first DDS over said serial communication network.

2. The communication network as recited in claim 1 wherein said serial communication network is based on a version of the IEEE 1394 communication standard.

3. The communication network as recited in claim 1 wherein said first DDS is copy protected under a copy protection format wherein said copy protection format is different from said first encryption format.

4. The communication network as recited in claim 1 wherein said first digital signal is transmitted from said first tuner on said serial communication network to said first CA unit via a first isochronous channel, and said OOB data is transmitted from said second tuner on said serial communication network to said first CA unit via a second isochronous channel.

5. The communication network as recited in claim 1 wherein said first tuner is also configured to generate a second digital signal encoded under a second encryption format and further comprising a second CA unit coupled to said serial communication network to receive said OOB data and said second digital signal, said second CA unit configured to generate a second DDS based on said OOB data and said second encryption format, said second CA unit also configured to transmit said second DDS over said serial communication network.

6. The communication network as recited in claim 1 wherein said first DDS is copy protected under a copy protection format and further comprising a media device coupled to said serial communication network, said media device configured to apply said copy protection format to said first DDS to generate an unscrambled digital signal for viewing.

7. The communication network as recited in claim 1 wherein said first CA unit further comprises a panel subunit configured to provide on screen display (OSD) support for said first CA unit.

8. The communication network as recited in claim 1 further comprising a modem device configured to perform two-way communications between said serial communication network and an external device.

31. The communication network as recited in claim 1 wherein said first CA unit comprises a first input to receive said first digital signal and a second input to receive said OOB data.

9. A communication network comprising:

a) signal reception means for receiving information from a service provider and coupled to a serial communication network, said signal reception means comprising;

a1) first tuning means for generating a first digital signal encoded under a first encryption format;

a2) second tuning means for generating out-of-band (OOB) data, wherein said first digital signal and said OOB data are transmitted on said serial communication network; and

b) first control means coupled to said serial communication network to receive said first digital signal and said OOB data, said first control means for generating a first decrypted digital signal (DDS) based on said OOB data and said first encryption format, said first control means also for transmitting said first DDS over said serial communication network.

10. The communication network as recited in claim 9 wherein said serial communication network is based on a version of the IEEE 1394 communication standard.

11. The communication network as recited in claim 9 wherein said first DDS is copy protected under a copy protection format wherein said copy protection format is different from said first encryption format.

12. The communication network as recited in claim 9 wherein said first digital signal is transmitted from said first tuning means on said serial communication network to said first control means via a first isochronous channel, and said OOB data is transmitted from said second tuning means on said serial communication network to said first control means via a second isochronous channel.

13. The communication network as recited in claim 9 wherein said first tuning means is also for generating a second digital signal encoded under a second encryption format and further comprising second control means coupled to said serial communication network to receive said OOB data and said second digital signal, said second control means for generating a second DDS based on said OOB data and said second encryption format, said second control means also for transmitting said second DDS over said serial communication network.

14. The communication network as recited in claim 9 wherein said first DDS is copy protected under a copy protection format and further comprising media means coupled to said serial communication network, said media means for applying said copy protection format to said first DDS to generate an unscrambled digital signal for viewing.

15. The communication network as recited in claim 9 wherein said first control means further comprises display interface means for providing on screen display (OSD) support for said first control means.

16. The communication network as recited in claim 9 further comprising communication means for performing two-way communications between said serial communication network and an external device.

32. The communication network as recited in claim 9 wherein said first control means comprises a first input means for receiving said first digital signal and a second input means for receiving said OOB data.

17. In a digital broadcasting environment, a method for implementing distributed conditional access (CA) over a serial communication network, said method comprising the steps of:

a) receiving information from a service provider using a receiver coupled to said serial communication network, said information being broadcasted in two different frequencies;

b) generating a first digital signal encoded under a first encryption format and out-of-band (OOB) data from said information using said receiver;

c) transmitting said first digital signal and said OOB data from said receiver over said serial communication network to a first control device, said first control device being a different network node than said receiver;

d) generating a first decrypted digital signal (DDS) from said first digital signal and said OOB data using said first control device, such that said first DDS is not encrypted under said first encryption format; and

e) transmitting said first DDS over said serial communication network to a first media device for rendering thereon.

18. The method as recited in claim 17 wherein said serial communication network is based on a version of the IEEE 1394 communication standard.

19. The method as recited in claim 17 further comprising the step f) of copy protecting said first DDS under a copy protection format wherein said copy protection format is different from said first encryption format.

20. The method as recited in claim 17 further comprising the steps of:

g) generating a second digital signal encoded under a second encryption format using said receiver;

h) transmitting said second digital signal from said receiver over said serial communication network to a second control device, said second control device being a different network node than said receiver and said first control device;

i) generating a second DDS from said second digital signal and said OOB data using said second control device, such that said second DDS is not encrypted under said second encryption format; and

j) transmitting said second DDS over said serial communication network to a second media device for rendering thereon.

21. A communication network comprising:

a) a first receiver decoder device configured to receive information from a service provider and coupled to a serial communication network, said first receiver decoder device also configured to generate a first digital signal encoded under a first encryption format;

b) a second receiver decoder device configured to receive information from a service provider and coupled to a serial communication network, said second receiver decoder device also configured to generate out-of-band (OOB) data, wherein said first digital signal and said OOB data are transmitted on said serial communication network; and

c) a first conditional access (CA) unit coupled to said serial communication network configured to receive said first digital signal and said OOB data, said first CA unit configured to generate a first decrypted digital signal (DDS) based on said OOB data and said first encryption format, said first CA unit also configured to transmit said first DDS over said serial communication network.

22. The communication network as recited in claim 21 wherein said serial communication network is based on a version of the IEEE 1394 communication standard.

23. The communication network as recited in claim 21 wherein said first DDS is copy protected under a copy protection format wherein said copy protection format is different from said first encryption format.

24. The communication network as recited in claim 21 wherein said first digital signal is transmitted from said first receiver decoder device on said serial communication network to said first CA unit via a first isochronous channel, and said OOB data is transmitted from said second receiver decoder device on said serial communication network to said first CA unit via a second isochronous channel.

25. The communication network as recited in claim 21 wherein said first digital signal is transmitted from said first receiver decoder device on said serial communication network to said first CA unit via a first asynchronous channel, and said OOB data is transmitted from said second receiver decoder device on said serial communication network to said first CA unit via a second asynchronous channel.

26. The communication network as recited in claim 21 wherein said first receiver decoder device is also configured to generate a second digital signal encoded under a second encryption format and further comprising a second CA unit coupled to said serial communication network to receive said OOB data and said second digital signal, said second CA unit configured to generate a second DDS based on said OOB data and said second encryption format, said second CA unit also configured to transmit said second DDS over said serial communication network.

27. The communication network as recited in claim 21 wherein said first DDS is copy protected under a copy protection format and further comprising a media device coupled to said serial communication network, said media device configured to apply said copy protection format to said first DDS to generate an unscrambled digital signal for viewing.

28. The communication network as recited in claim 21 wherein said first CA unit further comprises a panel subunit configured to provide on screen display (OSD) support for said first CA unit.

29. The communication network as recited in claim 21 further comprising a modem device configured to perform two-way communications between said serial communication network and an external device.

30. The communication network as recited in claim 21 wherein said first digital signal and said OOB data are first combined into a single stream before they are received by said CA unit and wherein said CA unit is configured to demultiplex said single stream.