Process for the broadcasting of conditional access programs permitting a progressive access to such programs

• US 5,442,701 A
• Filed: 12/27/1993
• Issued: 08/15/1995
• Est. Priority Date: 12/29/1992
• Status: Expired due to Term

• Current Assignee: France Telecom SA (Orange S.A.), Telediffusion De France SA
• Original Assignee: France Telecom SA (Orange S.A.), Telediffusion De France SA
• Inventors: Giachetti, Jean-Luc, Guillou, Louis, Gelly, Alain
• Primary Examiner(s): Cain, David C.
• Application Number:
  US08/172,817
• Time in Patent Office: 596 Days
• Field of Search: 380/9, 380/10, 380/20, 380/19
• US Class Current: 380/242
• CPC Class Codes: H04N 21/2541 Rights Management protecting software against unauthorised usage in a vending or licensing environment G06F21/10; security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/26613 for generating or managing keys in general key distribution for secret or secure communication involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP] H04L9/083; network support of key management H04L63/06; key management for network security in communication control or processing H04W12/04
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/4623 Processing of entitlement messages, e.g. ECM [Entitlement Control Message] or EMM [Entitlement Management Message] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/8453 by locking or enabling a set of features, e.g. optional functionalities in an executable program
• CPC Class Codes: H04N 21/8549 Creating video summaries, e.g. movie trailer retrieval in video databases by using presentations in form of a video summary G06F16/739
• 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 process for broadcasting conditional access programs which permits a progressive access. Scrambled program data is transmitted along with partial access checking messages and complete access checking messages such that subscribers having a partial access right may descramble portions of the scrambled data corresponding to information regarding only the identity of the conditional access programs, and subscribers having a complete access right may descramble the remainder of the scrambled data and view the conditional access programs. The conditional access programs may be television pictures, radio programs, or data broadcasts.

Claims

1. A method of broadcasting conditional access programs, comprising the steps of:

(a) scrambling data representing a content of at least conditional access program; and

(b) transmitting such scrambled data along with partial access checking messages and complete access checking messages to subscribers, said partial access checking messages permitting said subscribers to descramble portions of said scrambled data corresponding to information regarding only the identity of said at least one conditional access program, and said complete access checking messages permitting authorized subscribers to descramble a remainder of said scrambled data and view said at least one conditional access program.

2. The method according to claim 1, wherein said at least one conditional access program is a television program, and a video component of television signals is scrambled in step (a) and transmitted in step (b).

3. The method according to claim 2, wherein each television picture to be scrambled is horizontally subdivided into bands of a plurality of consecutive lines, and said scrambled data is derived from a first part of said bands while said partial access checking messages and said complete access checking messages are derived from a second part of said bands.

4. The method according to claim 2, wherein said television signals are subdivided into time periods, and said scrambled data is derived from information present in one part of each time period while said partial access checking messages and said complete access checking messages are derived from information present in a remainder of each of said time periods.

5. The method according to claim 1, wherein said partial access checking messages and said complete access checking messages are separately scrambled using first and second check word sequences, respectively, such that subscribers having a complete access right have access to both said first and second check word sequences, while subscribers having a partial access right only have access to said first check word sequence.

6. The method according to claim 1, wherein said partial access checking messages and said complete access checking messages are scrambled with a single check word sequence having a finite duration, such that subscribers having a complete access right have access to said check word sequence throughout its duration while subscribers having only a partial access right only have access to said check word sequence during a limited portion of its duration.

7. The method according to claim 1, wherein said at least one conditional access program is a television program, and an audio component of television signals is scrambled in step (a) and transmitted in step (b).

8. A method according to claim 1, wherein said at Least one conditional access program is a radio program.

9. A method according to claim 1, wherein said at least one conditional access program is a data broadcasting program.