International Business Machines Corporation

Ting Zhao

Richard L Spagna

Marco M Hurtado

Paul R Rettig

Kenneth Louis Milsted

Kenneth Carlin Nelson

James Christopher Mahlbacher

Douglas R Geisler

Christopher T Lehman

Qing Lu

A computer-based method with multilevel hashing for lookup of a complex nested object (such as access control list) which has a plurality of nesting levels and each level has at least one element. Method stores representatives of a complex nested object in a data structure at locations determined by recursive multilevel hashing of the complex nested object elements. When needed, a match for an inputted complex nested object is determined by applying the same recursive multilevel hashing to the inputted complex nested object, as used during the storing of the complex nested object, and performing integer comparisons with hash values of the stored complex nested object.

Matching of complex nested objects by multilevel hashing

A method on an end user system for creating additional copies onto at least one computer readable medium such as CDs, DVDs, ZipDisks&#x2122;, tape, Flash memory, and RAM. The method comprising the steps of: receiving encrypted content with associated usage conditions and a first hash value; receiving a selection from an end user to create at least one copy of the encrypted content onto at least one computer readable medium; sending a request to an online electronic store of the encrypted content selected to be copied; receiving from the electronic store a description of the content selected to be copied along with a second hash value; and determining if the first hash value received is identical to the second hash value and if the first hash and the second hash value is identical authorizing the creating additional copies onto at least one computer readable medium.

Updating usage conditions in lieu of download digital rights management protected content

A method and system for forming a data table in memory on an end user system. The data table forming a library index of storage locations to electronic digital content in memory. The method consists of retrieving an encrypted file from storage. The file has a beginning, an end and a trailer section located just prior to the end. The file is read from the end a predetermined distance to verify if an identifier is present. Reading and decrypting the trailer section from the file read. Determining if there are any updates in the trailer section. In the case there are no updates in the trailer section then decrypting the reference table containing one or more data table location indicators for data items with the first decrypting key. Next, decrypting one or data items with the first decrypting key. Populating the data table with data items at locations specified in the reference table.

Method and system for securing local database file of local content stored on end-user system

Growing community of inventors

Coral Springs, FL, United States of America

Ting Zhao