Abstract: The invention provides a headend system, a receiver, a smartcard and a conditional access system enabling distribution of multiple variants of a part of a digital signal, such as multiple variants of an audio part or a video part of a data stream, without requiring receivers to be updated. The digital signal generated by the headend system enables a receiver to receive and process the digital signal without requiring identification of the copies in the second digital signal. Error handling capabilities of the receiver ensure that only one copy is used in the output of the receiver. The error handling capabilities are triggered by having the receiver use one decryption key for descrambling all copies, resulting in one copy being descrambled correctly and the other copies being descrambled incorrectly.

Abstract: A method and a system for generating a scrambled data stream is described, wherein the method comprises: providing a code book comprising code information for scrambling data in data stream comprising one or more service streams; generating a control word request associated with at least one crypto period in at least one of said service streams; in response to said control word request, generating on the basis of said code information at least one control word associated with said crypto period in said service stream; and, scrambling data associated with at least one of said service streams using said control word.

Abstract: The invention provides for a method and a device for the detection of a watermark in a signal. A first signal is compared with two or more second signals. The second signal with the closest match contains the same watermark as in the first signal. Data indicative for the second signal with the closest match is output as an indication of the watermark in the first signal. The invention further provides for a head-end system that provides watermarked content from which the watermarks are detectable by the watermark detection device.

Abstract: A method and a system of transmitting one or more control words to a receiver system is described, wherein the one or more control words are generated by a scrambling system for scrambling during a crypto period data packets in a service stream. The method involves transmission of at least one service stream and a stream of entitlement control messages associated with said service stream to the receiver system, each entitlement control message comprising at least one encrypted control word; and controlling the processing load of the receiver system by modifying the duration of said crypto period.

Abstract: A method and a system for generating a scrambled data stream is described, wherein the method comprises: providing a code book comprising code information for scrambling data in data stream comprising one or more service streams; generating a control word request associated with at least one crypto period in at least one of said service streams; in response to said control word request, generating on the basis of said code information at least one control word associated with said crypto period in said service stream; and, scrambling data associated with at least one of said service streams using said control word.

Abstract: A method and a system for providing control words to at least one a receiver are described wherein said receiver is associated with a secure module. The method comprises the steps of receiving at least part of a code book comprising code information for descrambling one or more service streams in a scrambled data stream sent to said receiver; providing a control word request associated with at least one crypto period in at least one of said service streams; and, in response to said control word request, generating on the basis of said code information at least one control word for descrambling data in said service stream and associated with said crypto period.

Abstract: The invention provides a headend system, a receiver, a smartcard and a conditional access system enabling distribution of multiple variants of a part of a digital signal, such as multiple variants of an audio part or a video part of a data stream, without requiring receivers to be updated. The digital signal generated by the headend system enables a receiver to receive and process the digital signal without requiring identification of the copies in the second digital signal. Error handling capabilities of the receiver ensure that only one copy is used in the output of the receiver. The error handling capabilities are triggered by having the receiver use one decryption key for descrambling all copies, resulting in one copy being descrambled correctly and the other copies being descrambled incorrectly.

Abstract: Various embodiments of the invention provide a method, a smartcard, a conditional access module (CAM) of a receiver and a receiver, such as e.g. a set-top box, for securely providing a control word from the smartcard to the CAM. In various embodiments, diversification data from the smartcard and the CAM is used to make the encryption key and decryption key to encrypt and decrypt the control word in the smartcard and CAM, respectively, dependent on a user interaction with the receiver, such as e.g. selecting a service in the set-top box.