Hitachi, Ltd.

Yumiko Yokohari

Yoshinori Sato

Keisei Fujiwara

Takayuki Suzuki

Michio Oikawa

Masayuki Yoshino

Kunihiko Harada

Tatsuya Nakae

A database system including: a database server for storing registration information including encrypted data encrypted using a probabilistic encryption method; and a terminal. The terminal includes: an encryption unit; a decryption unit; an encrypted search query generating unit for generating an encrypted search query obtained by encrypting a search query used for retrieving the encrypted data; and an additional processing unit for encrypting a search condition of a plaintext and transmitting a data acquisition request including the encrypted search condition. The database server holds database operation command definition information and search additional information. The database server includes: a database operation command generating unit for generating a database operation command by converting the data acquisition request on the basis of the database operation command definition information; and a database control unit for acquiring encrypted data satisfying the search condition by using the database operation command and the search additional information.

Database system and data retrieval method

An information providing apparatus for collecting data including personal information and distributing the data to a user terminal performs anonymization processing for converting data, which an individual who is an owner of personal information allows to use, into data with which the individual cannot be identified using multiple parameters, thus generating multiple anonymized data protecting the, privacy of the individual. Since each of the anonymized data is anonymized using a different parameter, the amount of information of each of the anonymized data is different. Then, when a request is received from a user terminal, anonymized data that can be provided to the user are identified from among multiple generated anonymized data on the basis of the reliability of the user who uses the user terminal.

Privacy protection-type data providing system

Growing community of inventors

Tokyo, Japan

Yumiko Yokohari