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:
Sep. 11, 2018
Filed:
Jul. 04, 2014
Nagravision S.a., Cheseaux-sur-Lausanne, CH;
Marco Macchetti, Casnate con Bernate, IT;
Jerome Perrine, Romanel sur Morges, CH;
Patrick Servet, Cheseaux-sur-Lausanne, CH;
Didier Hunacek, Blonay, CH;
Nagravision S.A., Cheseaux-sur-Lausanne, CH;
Abstract
Method for securing control words within a decoder in charge of descrambling digital content protected by these control words, comprising the following steps: for each descrambling unit of this decoder, loading in a directory a pairing key referenced by an identifier associating said key to a descrambling unit; receiving at least one encrypted control word referenced by an indication allowing to identify the descrambling unit for which it is intended; decrypting the control word by using a first key shared with a security module; identifying in the directory the pairing key whose identifier corresponds to the indication of destination associated to the control word; encrypting this control word by using this pairing key; and storing in a register the control word in a chronological and referenced way.