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:
Oct. 27, 2015
Filed:
Dec. 14, 2012
Thomson Licensing, Issy de Moulineaux, FR;
Jean-Marie Steyer, Cesson Sevigne, FR;
Didier Roustide, Cesson Sevigne, FR;
Thomson Licensing, Issy-les Moulineaux, FR;
Abstract
A receiver comprises a security processor and a first memory that stores software code or second stage authentication key and a signature for the software or the second stage key. The receiver also stores a plurality of verification keys (PUAK). When the receiver is switched on or reset, the software or second stage key and the signature are loaded from the first memory. The security processor then loads a PUAK and uses it to verify the signature. In case of successful verification, the software code or second stage key is used and the verification method ends; it is then possible to activate CA specific functions in the receiver. However, if the verification is unsuccessful, then it is verified if there are untried PUAKs. If there are no untried signatures, then the verification has failed and the software cannot be verified; the verification method ends. If there are untried signatures, then the next PUAK is loaded.