Method and apparatus for geographically limiting service in a conditional access system

• US 6,744,892 B2
• Filed: 03/03/2003
• Issued: 06/01/2004
• Est. Priority Date: 04/03/1995
• Status: Expired due to Fees

• Current Assignee: Tech 5 SAS
• Original Assignee: Scientific-Atlanta Incorporated (Cisco Systems, Inc.)
• Inventors: Pinder, Howard G., Akins, Glendon L. III, Wasilewski, Anthony J.
• Primary Examiner(s): Smithers, Matthew
• Application Number:
  US10/377,416
• Publication Number:
  US 20030169879A1
• Time in Patent Office: 456 Days
• Field of Search: 380/239, 380/240, 380/241, 380/242, 380/210
• US Class Current: 380/241
• CPC Class Codes: H04J 2203/008 Support of video
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management
• CPC Class Codes: H04L 63/04 for providing a confidential data exchange among entities communicating through data packet networks
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/045 wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption cryptographic mechanisms or cryptographic arrangements using a plurality of keys or algorithms H04L9/14
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04N 21/2265 Server identification by a unique number or address, e.g. serial number network arrangements, protocols or services for addressing or naming H04L61/00
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/26606 for generating or managing entitlement messages, e.g. Entitlement Control Message [ECM] or Entitlement Management Message [EMM] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/4524 involving the geographical location of the client retrieval from the Internet by querying based on geographical locations G06F16/9537; systems specially adapted for using geographical information in broadcast systems H04H60/70; protocols in which the network application is adapted for the location of the user terminal in communication control or processing H04L67/52; services making use of the location of users or terminals in wireless networks H04W4/02; locating users or terminals in wireless networks H04W64/00
• CPC Class Codes: H04N 21/63345 by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 7/162 Authorising the user terminal, e.g. by paying; Registering the use of a subscription channel, e.g. billing
• 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
• CPC Class Codes: H04N 7/17354 : in an intermediate station common to a plurality of user terminals

Abstract

A cable television system provides conditional access to services. The cable television system includes a headend from which service “instances”, or programs, are broadcast and a plurality of set top units for receiving the instances and selectively decrypting the instances for display to system subscribers. The service instances are encrypted using public and/or private keys provided by service providers or central authorization agents. Keys used by the set tops for selective decryption may also be public or private in nature, and such keys may be reassigned at different times to provide a cable television system in which piracy concerns are minimized.

Claims

1. A receiver located at a geographic location for receiving and selectively displaying a service instance, the receiver comprising:

a port for receiving an encrypted service instance and entitlement information associated therewith, wherein at least a portion of the entitlement information includes geographic reception information;

a first microprocessor for activating display of the service instance;

a secure element coupled to the first microprocessor, the secure element comprising;

a memory for storing a geographic location indicator indicative of the geographic location of the receiver; and

a second microprocessor for processing the geographic reception information and for using the processed geographic reception information with the geographic location indicator to determine whether the receiver is entitled to the service instance; and

wherein the first microprocessor activates display of the service instance when the secure element determines that the receiver is entitled to the service instance.

2. The receiver of claim 1, wherein in response to determining that the receiver is not entitled to the received encrypted service instance, the service instance is not decrypted for display.

3. The receiver of claim 1, wherein the memory of the secure element is accessible only to the second microprocessor.

4. The receiver of claim 1, wherein the geographic reception information comprises a blackout/spotlight field indicative of how the geographic reception information is to be used by the receiver.

5. The receiver of claim 4, wherein the blackout/spotlight field indicates whether the service instance is geographically limited, and, if so, whether the service instance is limited to within a particular geographic region or to without the particular geographic region.

6. The receiver of claim 1, wherein:

the geographic reception information is indicative of a geographic region; and

the receiver further includes a decryptor for decrypting the service instance when the geographic location indicator is within the geographic region indicated by the geographic reception information.

7. The receiver of claim 1, wherein:

the geographic reception information is indicative of a geographic region; and

the receiver further includes a decryptor for decrypting the service instance when the geographic location indicator is not within the geographic region indicated by the geographic reception information.

8. The receiver of claim 1, wherein the geographic location indicator includes x and y coordinates of a coordinate system.

9. The receiver of claim 8, wherein the geographic reception information comprises an x centroid, a y centroid, and a radius value, and wherein the x centroid, the y centroid, and the radius define a square geographic region within the coordinate system.

10. The receiver of claim 9, further comprising:

a decryptor for decrypting the service instance when the geographic location indicator is within the square geographic region.

11. The receiver of claim 9, further comprising:

a decryptor for decrypting the service instance when the geographic location indicator is not within the square geographic region.

12. A conditional access system for selectively providing service instances to viewers, the conditional access system comprising:

a plurality of set top terminals located at geographic locations for selectively providing for display of the service instances, each of the set top terminals comprising;

a port for receiving an encrypted service instance and entitlement information associated therewith, wherein at least a portion of the entitlement information includes a geographic reception information;

a first microprocessor for activating display of the service instance;

a secure element coupled to the first microprocessor, the secure element comprising;

a memory for storing a geographic location indicator indicative of a location of a given terminal; and

a second microprocessor for processing at least a portion of the entitlement information and for using the processed entitlement information with the geographic location indicator to determine whether the given terminal is entitled to the service instance;

wherein the first microprocessor activates display of the service instance when the secure element determines that the given terminal is entitled to the service instance; and

an entitlement agent coupled to the plurality of receivers for providing the encrypted service instance and the entitlement information.

13. The conditional access system of claim 12, wherein in response to determining that the terminal is not entitled to the received encrypted service instance, the service instance is not decrypted for display.

14. The conditional access system of claim 12, wherein the geographic reception information comprises a blackout/spotlight field indicative of how the geographic reception information is to be used by the terminal.

15. The conditional access system of claim 14, wherein the blackout/spotlight field indicates whether the service instance is geographically limited and, if so, whether the service instance is limited to within a particular geographic region or to without the particular geographic region.

16. The conditional access system of claim 12, wherein the memory of the secure element is accessible only to the microprocessor of the secure element.

17. The conditional access system of claim 12, wherein the entitlement information includes the geographic reception information in the form of an x centroid, a y centroid, and a radius value for defining an entitlement region.

18. The conditional access system of claim 17, further comprising additional entitlement agents for sending additional entitlement information that can be different for each entitlement agent and different for each service instance.

19. The conditional access system of claim 17, wherein a given receiver is entitled to an instance of service when the geographic indicator of the given receiver is within the entitlement region.

35. The conditional access system of claim 17, wherein a given receiver is entitled to an instance of service when the geographic location indicator of the given receiver is without the entitlement region.

36. The conditional access system of claim 12, wherein a given receiver is entitled to an instance of service when the geographic indicator of the given receiver is within the entitlement region.

37. The conditional access system of claim 12, wherein a given receiver is entitled to an instance of service when the geographic indicator of the given receiver is without the entitlement region.

20. A method for providing selective viewing of a service instance in a conditional access system comprising a receiver for selectively activating display of the service instance and an entitlement agent coupled to the receiver for selectively entitling the receiver to display the service instance based on a geographic location of the receiver, the method comprising, in the receiver, the steps of:

receiving an encrypted service instance and entitlement information from the entitlement agent;

decoding geographic reception information from the entitlement information;

determining from the decoded geographic reception information a geographic region;

determining from the geographic region and a geographic location indicator whether the receiver is entitled to display the service instance; and

decrypting, when the receiver is entitled to display the service instance, the encrypted service instance.

21. The method of claim 20, wherein:

the geographic reception information represents an entitled geographic region; and

the determining step comprises the step of determining that the receiver is entitled when the geographic location indicator is within the represented entitled geographic region.

22. The method of claim 20, wherein:

the geographic reception information represents an unentitled geographic region; and

the determining step comprises the step of determining that the receiver is entitled when the geographic location indicator is not within the represented unentitled geographic region.

23. The method of claim 20, further comprising, in the receiver, the step of:

processing the geographic reception information to recover therefrom an x centroid, a y centroid, and a radius, all of which define the geographic region.

24. The method of claim 23, wherein when the geographic location information intersects the geographic region then the receiver is entitled to the instance of service.

25. The method of claim 23, wherein when the geographic location information does not intersect the geographic region then the receiver is not entitled to the instance of service.

38. The method of claim 20, wherein the geographic location indicator is stored in a memory at the receiver.

26. A method for providing selective viewing of a service instance in a conditional access system comprising a receiver for selectively activating display of the service instance and an entitlement agent for selectively entitling the receiver to display the service instance, the method comprising the steps of:

representing a two dimensional grid, wherein the two dimensional grid represents entitlements granted by the entitlement agent for an instance of service; and

determining whether the receiver is entitled to the instance of service by using the two dimensional grid and a receiver entitlement indicator, the receiver entitlement indicator associated with a point in the two dimensional grid.

27. The method of claim 26, wherein the determining step further includes:

determining a subportion of the represented two dimensional grid, the subportion being a blackout/spotlight field.

28. The method of claim 27, wherein the receiver is entitled to the instance of service when the receiver entitlement indicator is within the spotlight field or without the blackout field.

29. The method of claim 27, wherein the receiver is not entitled to the instance of service when the receiver entitlement indicator is without the spotlight field or within the blackout field.

30. The method of claim 26, further including the step:

prior to the determining step, receiving at the receiver a message having at least one subportion indicator.

31. The method of claim 30, wherein the at least one subportion indicator includes an x centroid, a y centroid, defining a given point in the two dimensional grid, and an area indicator for defining a blackout/spotlight area around the given point.

32. The method of claim 31, wherein the blackout/spotlight area defines a subportion of the represented two dimensional grid having a subportion x min, a subportion x max, a subportion y min, and a subportion y max.

33. The method of claim 32, wherein the receiver is entitled to the instance of service when the receiver entitlement indicator is within the spotlight area or without the blackout area.

34. The method of claim 32, wherein the receiver is not entitled to the instance of service when the receiver entitlement indicator is without the spotlight area or within the blackout area.