Patent ID: 8798269
Filing Date: 2014-08-05
Classification: H04N

Abstract:
1. A method for secured broadcasting of a digital data flow between a technical platform and at least one terminal, the method comprising: transmitting a scrambled and multiplexed digital data flow with at least one message (ECM) including a control key (CW) encrypted with a channel key (CC); descrambling in a secured memory area of the terminal, the scrambled digital data flow from the control key (CW) obtained according to the following substeps: sending to the technical platform a request including the identifier (IUi) of the terminal; generating a first secret key (CSk) from a cryptographic mechanism using a unique ciphering key (BSKn) and the identifier (IUi) of the terminal, and ciphering said channel key (CC) with the first secret key (CSk) to obtain a ciphered message (eCCk); transmitting the ciphered message (eCCk) to the terminal; deciphering the ciphered message (eCCk) received by the terminal using a second secret key stored in the terminal during a production phrase of the terminal to obtain the channel key (CC), and obtaining the control key (CW) resulting from the deciphering of the message (ECM) from the channel key (CC); wherein the generating step comprises a substep for identifying a ciphering key index associated with the identifier (IUi) of the terminal and stored within a server for managing rights relating to the contents of the digital data flow; and determining the ciphering key (BSKn) from a plurality of ciphering keys archived in another server for generating secret keys (CSk), corresponding to the index.