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:
May. 23, 2017
Filed:
Oct. 14, 2011
Andrew Augustine Wajs, Hoofddorp, NL;
Arnoud Evert Van Foreest, Hoofddorp, NL;
Andrew Augustine Wajs, Hoofddorp, NL;
Arnoud Evert Van Foreest, Hoofddorp, NL;
IRDETO B.V., LS Hoofddorp, NL;
Abstract
The invention provides for a solution enabling obtaining a control word in the client. The client device has a unique binary identification. An input transformed control word is mapped from an input transform domain to an output transform domain to thereby obtain an output transformed control word by successively applying a transformation function to the input transformed control word using each compound of seeds from the set successively as an input to the successive transformation functions. Each of the successive transformation functions is one of a regular transformation function, a first special transformation function and a second special transformation function. The obtained control word can be used to decrypt one of two copies of a part of content data. The copy that can be decrypted contains a watermark representing either a binary '0' or a binary '1' and represents a bit of the unique binary identification of the client device.