MANAGEMENT METHOD OF RIGHTS OF A CONTENT ENCRYPTED AND STORED IN A PERSONAL DIGITAL RECORDER

摘要

THE AIM OF THE PRESENT INVENTION IS TO PROPOSE A STORAGE METHOD OF AN EVENT ENCRYPTED BY CONTROL WORDS (CW) THAT GUARANTEES THE ACCESS TO THIS EVENT WHICHEVER THE MOMENT IS DESIRED, EVEN IF CERTAIN MODIFICATIONS IN THE DESIGNATION OF THE IDENTIFIERS OF THESE EVENTS OCCUR BETWEEN THE MOMENT OF STORAGE AND THE MOMENT OF VIEWING. THIS AIM IS ACHIEVED BY A STORAGE METHOD OF SUCH AN EVENT IN THE RECEPTION AND DECRYPTION UNIT (STB) CONNECTED TO A SECURITY UNIT (SC), SAID CONTROL WORDS (CW) AND THE NECESSARY RIGHTS BEING CONTAINED IN CONTROL MESSAGE (ECM), CHARACTERIZED IN THAT IT COMPRISES THE FOLLOWING STAGES: - STORING THE ENCRYPTED EVENT AS WELL AS THE CONTROL MESSAGE (ECM) IN THE STORAGE UNIT, - TRANSMITTING THE CONTROL MESSAGE (ECM) TO THE SECURITY UNIT (SC), - VERIFYING IF THE ACCESS RIGHTS TO THIS EVENT ARE CONTAINED IN THE SECURITY UNIT (SC), - IF THIS IS THE CASE, DETERMINING A RECEIPT (Q) OF ALL OR PART OF THE CONTROL MESSAGE (ECM) THANKS TO A SECRET KEY (K) CONTAINED IN THE SECURITY UNIT (SC) AND SPECIFIC TO EACH SECURITY UNIT (SC), - STORING THIS RECEIPT (Q) IN THE STORAGE UNIT. FIG. 1