Method and system for transmission/reception of encrypted digital signal.

摘要

A digital information signal transmitting/receiving method and system having a transmitter (100) for transmitting an encrypted digital information signal and a plurality of receivers (200) for receiving the encrypted digital information signal from the transmitter (100). The transmitter (100) simultaneously distributes a plurality of identification codes associated with the receivers (200) ahead of the digital information signal. Then, the digital information signal is distributed to the receivers. The receivers (200) detect particular, or their own, identification codes from the plurality of identification signals assigned to the receivers (200). The received encrypted digital information signal is decrypted into the original information on the basis of the particular identification codes associated with the corresponding receivers or the recorders (300). Either the receivers (200) or the recorders (300) generate an information request signal. The transmitter (100) is responsive to this information request signal to add to the digital information signal identification signals for identifying the receivers (200) or the recorders (300) which generated the information request signal. The recorders (300) control the received information signal to be recorded in response to the identification signals received by the receivers (200).