Abstract: A method of authenticating data transmitted in a digital transmission system, in which the method comprises the steps, prior to transmission, of determining at least two encrypted values for at least some of the data, each encrypted value being determined using a key of a respective encryption algorithm, and outputting said at least two encrypted values with said data.

Abstract: A method of authenticating data transmitted in a digital transmission system, in which the method comprises the steps, prior to transmission, of determining at least two encrypted values for at least some of the data, each encrypted value being determined using a key of a respective encryption algorithm, and outputting said at least two encrypted values with said data.

Abstract: A method of authenticating data transmitted in a digital transmission system, in which the method comprises the steps, prior to transmission, of determining at least two encrypted values for at least some of the data, each encrypted value being determined using a key of a respective encryption algorithm, and outputting said at least two encrypted values with said data.

Abstract: A method of authenticating data transmitted in a digital transmission system, in which the method comprises the steps, prior to transmission, of determining at least two encrypted values for at least some of the data, each encrypted value being determined using a key of a respective encryption algorithm, and outputting said at least two encrypted values with said data.

Abstract: A method of authenticating data transmitted in a digital transmission system, in which the method comprises the steps, prior to transmission, of determining at least two encrypted values for at least some of the data, each encrypted value being determined using a key of a respective encryption algorithm, and outputting said at least two encrypted values with said data.

Abstract: A method of authentification of data sent in a digital transmission characterized by the organization and authentification of the data prior to transmission into a hierarchy of at least one root directory unit (75), subdirectory unit (76) and file unit (77), data in a file (77) being acted upon by an authentification algorithm and an associated file authentification value (82) stored in the referring subdirectory unit (77), this file authentification value (82) being in turn acted upon by an authentification algorithm and an associated subdirectory authentification value (79) stored in the referring root directory. Other aspects of the invention relate to the authentification of a second root directory (78) by generation of a second authentification value (83) and the authentification of data before encapsulation in tables or sections of a transport stream.

Abstract: A method of authentification of data sent in a digital transmission characterised by the organisation and authentification of the data prior to transmission into a hierarchy of at least one root directory unit (75), subdirectory unit (76) and file unit (77), data in a file (77) being acted upon by an authentification algorithm and an associated file authentification value (82) stored in the referring subdirectory unit (77), this file authentification value (82) being in turn acted upon by an authentification algorithm and an associated subdirectory authentification value (79) stored in the referring root directory. Other aspects of the invention relate to the authentification of a second root directory (78) by generation of a second authentification value (83) and the authentification of data before encapsulation in tables or sections of a transport stream.

Abstract: A method of authenticating data transmitted in a digital transmission system, in which the method comprises the steps, prior to transmission, of determining at least two encrypted values for at least some of the data, each encrypted value being determined using a key of a respective encryption algorithm, and outputting said at least two encrypted values with said data.

Abstract: A combined computer and decoder system for receiving broadcast digital data transmissions, characterized in that the decoder (2020) comprises a routing means (2032), broadcast digital data received at the decoder (2020) and destined for the computer (2027) being identified and routed to applications within the computer by said routing means. The computer (2027) may further include control means (2038) for controlling the configuration of the decoder, such as the selected channel frequency of the decoder.