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:
Nov. 17, 2009
Filed:
Jun. 24, 2005
Koichi Kamijo, Yokohama, JP;
Koichi Kamijo, Yokohama, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
Reduces message length of encrypted message to be transmitted selectively to plurality of decrypting devices. An encrypting device includes a generating unit for generating node associating information configured to associate respective terminal nodes in a tree structure with each decrypting device in relation to a group of decrypting devices enabled for decryption, a extracting unit for extracting a decryption enabled node containing decrypting devices in descendant terminal nodes and not containing a decrypting device with decryption disabled in any of the descendant terminal nodes, and a unit for encrypting the message by use of a node encryption key for the decryption enabled node. Decrypting devices include specifying unit for specifying terminal node associated with decrypting device based on node associating information, and a decrypting unit for decrypting encrypted message using a node decryption key for any decryption enabled nodes ranging from terminal node to root node thereof.