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:
Apr. 12, 2011
Filed:
Apr. 02, 2008
Jeffrey Bruce Lotspiech, San Jose, CA (US);
Dalit Naor, Palo Alto, CA (US);
Simeon Naor, Palo Alto, CA (US);
Jeffrey Bruce Lotspiech, San Jose, CA (US);
Dalit Naor, Palo Alto, CA (US);
Simeon Naor, Palo Alto, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A tree is used to partition stateless receivers in a broadcast content encryption system into subsets. Two different methods of partitioning are disclosed. When a set of revoked receivers is identified, the revoked receivers define a relatively small cover of the non-revoked receivers by disjoint subsets. Subset keys associated with the subsets are then used to encrypt a session key that in turn is used to encrypt the broadcast content. Only non-revoked receivers can decrypt the session key and, hence, the content.