Method of distributing encrypted portions of an audiovisual programme

• US 20050232418A1
• Filed: 07/18/2003
• Published: 10/20/2005
• Est. Priority Date: 07/24/2002
• Status: Abandoned Application

• Current Assignee: Thomson Licensing SA (Vantiva SA), Xellia Pharmaceuticals APS
• Original Assignee: Xellia Pharmaceuticals APS
• Inventors: Guillotel, Philippe, Francois, Edouard, Bordes, Philippe
• Application Number:
  US10/522,118
• Publication Number:
  US 20050232418A1
• Time in Patent Office: Days
• US Class Current: 380/200
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/2543 Billing , e.g. for subscription services payment schemes, architectures or protocols G06Q20/00; e-commerce G06Q30/00; arrangements for billing for the use of broadcast information or broadcast-related information H04H60/21
• CPC Class Codes: H04N 21/25875 involving end-user authentication restricting access to computer systems by authenticating users using a predetermined code G06F21/33; arrangements for secret or secure communication including means for verifying the identity or authority of a user of the system H04L9/32; networks authentication protocols H04L63/08; authentication in wireless network security H04W12/06
• 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 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• 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 21/6175 involving transmission via Internet broadcast-related systems characterised by the transmission system being the Internet H04H60/82
• CPC Class Codes: H04N 21/6187 involving transmission via a telephone network, e.g. POTS
• 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 7/165 Centralised control of user terminal subsequent to an upstream request signal H04N7/17345; Registering at central by two-way working H04N7/17309
• 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

The method of distributing encrypted portions of an audiovisual programme to user terminals, in which the successive portions of the programme are encrypted with the aid of different keys, consists, on initiation, from a user terminal, of a telephone communication with a call centre, in transmitting in sequence from this call centre and during the telephone communication the keys to the user terminal, doing so in a manner synchronized with the distribution of the successive encrypted portions of the programme.

Claims

1. Method of distributing encrypted portions of an audiovisual programme to user terminals, in which the successive portions of the programme are encrypted with the aid of different keys, wherein it consists, on initiation, from a user terminal, of a telephone communication with a call centre, in transmitting in sequence from this call centre and during the telephone communication the keys to the user terminal, doing so in a manner synchronized with the distribution of the successive encrypted portions of the programme.

2. Method according to claim 1, in which the telephone communication utilizes an Internet protocol.

3. Method according to claim 1, in which synchronization time codes are transmitted with the keys to the user terminal.

4. Method according to claim 1, in which, on completion of the telephone communication with a user terminal, a duration of telephone communication is determined in the call centre so as to draw up a bill corresponding to the reception of the programme by the user terminal.

5. Method according to claim 1, in which the call centre is a centre for receiving telephone calls of a telephone operator.

6. Decoder for receiver of audiovisual programmes, in which successive portions of a programme are decrypted with the aid of a succession of different keys, wherein it is designed to be connected up, by way of a telephone communication interface, to a call centre and to recover the successive keys in sequence during the communication with the call centre and to do so in a manner synchronized with the decryption of the successive portions of the programme,

the said decoder preferably being able to decrypt encrypted programme portions distributed according to a method in accordance with claim 1.

7. Decoder according to claim 6, designed to recover synchronization time codes from the call centre in association with the keys.

8. Decoder according to claim 6, in which the communication interface is a telephone modem.

9. Decoder according to claim 8, in which the communication interface is an ADSL modem.

10. Decoder according to claim 6, in which the communication interface utilizes an Internet protocol.

11. Method of decoding an audiovisual programme, according to which successive portions of the programme are decrypted with the aid of a succession of different keys, wherein it consists in connecting up, by way of a telephone communication interface, to a call centre so as to recover the successive keys in sequence during the communication with the call centre and to do so in a manner synchronized with the decryption of the successive portions of the programme

the said method preferably being intended to be implemented by means of a decoder in accordance with claim 6.

12. Decryption routine for decrypting successive portions of an audiovisual programme with the aid of a succession of different keys, wherein it is designed to set up a telephone communication with a call centre having a predefined call number and in that it is designed to recover the successive keys from the call centre during the telephone communication and to do so in a manner synchronized with the decryption of the successive portions of the programme,

the said routine preferably being intended to implement a decoding method in accordance with claim 11.