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:
Jul. 22, 2008
Filed:
Dec. 19, 2001
Bartholomeus Johannes Van Rijnsoever, Eindhoven, NL;
Johan Cornelis Talstra, Eindhoven, NL;
Antonius Adriaan Maria Staring, Eindhoven, NL;
Bartholomeus Johannes Van Rijnsoever, Eindhoven, NL;
Johan Cornelis Talstra, Eindhoven, NL;
Antonius Adriaan Maria Staring, Eindhoven, NL;
Irdeto Eindhoven B.V., Eindhoven, NL;
Abstract
A transmitter provides receivers conditional access to data transmitted via a network. A content encryptor is used to encrypt the data under control of a same authorization key before it is transmitted to all receivers. The transmitter has a storage with a plurality of device keys. A further encryptor is used for producing a key block with a plurality of entries, where each entry is associated with a respective one of the device keys. At least some of the entries contain a representation of the authorization key encrypted with the associated device key. The transmitter transmits the same key block to all receivers. The receiver has a subset of the device keys. A first decryptor is used to retrieve the authorization key by decrypting at least one entry of the key block that is associated with one of the device keys of the receiver. A second decryptor is used for decrypting the data under control of the authorization key.