The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 02, 2004
Filed:
Mar. 24, 2000
Christian Benardeau, Bussy Saint Georges, FR;
Canal+ Societe Anonyme, Paris, FR;
Abstract
A method of restricting access to recorded digital data on a digital support medium ( ) using an integrated circuit e.g. on a smart card ( ) containing a first decryption key (Kf) characterized in encrypting with a corresponding encryption key (Kf) one or more elements of the volume descripter (V) of the support medium ( ), recording the encrypted elements of the volume descripter together with non-encrypted data on the support medium and, when accessing the support medium ( ), using the integrated circuit decryption key (Kf) to decrypt the encrypted elements of the volume descripter (V) and to supply a reader ( ) with these elements so as to permit the reading and/or writing of non-encrypted data on the support medium ( ).