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. 21, 2009
Filed:
Jan. 08, 2002
Jeffrey Bruce Lotspiech, San Jose, CA (US);
Dalit Naor, Palo Alto, CA (US);
Sigfredo Ismael Nin, Morgan Hill, CA (US);
Florian Pestoni, Mountain View, CA (US);
Jeffrey Bruce Lotspiech, San Jose, CA (US);
Dalit Naor, Palo Alto, CA (US);
Sigfredo Ismael Nin, Morgan Hill, CA (US);
Florian Pestoni, Mountain View, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method for enforcing compliance in both the copy protect domain and service subscription domain for streamed multicast data. Each content is encrypted with a title key that itself is encrypted with a channel unique key which is a hash of a session key and a channel key. A compliant player is given the channel key upon registration for a subscription service (representing subscription protection) and is also given device keys upon activation (representing copy protection) for decrypting the session key. Consequently, the channel unique key can be obtained (and, hence, the content decrypted) only by a player that is compliant with both copy protection rules and subscription rules. The channel key can be refreshed periodically as subscriptions change or expire.