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. 03, 2011
Filed:
May. 07, 2007
Augustin J. Farrugia, Cupertino, CA (US);
Gianpaolo Fasoli, Palo Alto, CA (US);
Jean-francois Riendeau, Campbell, CA (US);
Rod Schultz, San Francisco, CA (US);
Augustin J. Farrugia, Cupertino, CA (US);
Gianpaolo Fasoli, Palo Alto, CA (US);
Jean-Francois Riendeau, Campbell, CA (US);
Rod Schultz, San Francisco, CA (US);
Apple Inc., Cupertino, CA (US);
Abstract
For digital rights management (DRM) of e.g. digitally delivered music or video, a technique to make the decryption keys more secure. The technique fragments a message (song or video or other) into a number of portions, and uses a different decryption key for each portion. Each of the various keys is a function of the preceding key, in one version. In another version, each key is a function of a seed value and of the particular portion of the material with which the key is associated.