US 11,902,418 B2
Registration device, search operation device, and data management device
Takato Hirano, Tokyo (JP); Yutaka Kawai, Tokyo (JP); Yoshihiro Koseki, Tokyo (JP); and Satoshi Yasuda, Tokyo (JP)
Assigned to Mitsubishi Electric Corporation, Tokyo (JP)
Filed by MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Filed on May 23, 2022, as Appl. No. 17/750,902.
Application 17/750,902 is a continuation of application No. PCT/JP2020/000894, filed on Jan. 14, 2020.
Prior Publication US 2022/0286271 A1, Sep. 8, 2022
Int. Cl. H04L 29/06 (2006.01); H04L 9/06 (2006.01); H04L 9/08 (2006.01); G06F 21/00 (2013.01)
CPC H04L 9/0618 (2013.01) [H04L 9/065 (2013.01); H04L 9/0819 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A search operation device comprising:
processing circuitry configured to:
accept a search keyword and a user key; and
generate a search query by using the search keyword and a user tag key included in the user key, wherein
the user tag key has a plurality of flag values based on a plurality of attribute values which identify a plurality of attributes of a user and one or more tag attribute keys based on one or more aggregate values generated by aggregating the plurality of attribute values, and
the processing circuitry further configured to:
generate a search-purpose aggregate flag indicating one or more aggregate values each configured of one or more flag values, by aggregating the plurality of flag values included in the user tag key,
generate, by using the search-purpose aggregate flag, search position information which identifies one or more attribute elements for use in searching among a plurality of attribute elements included in an encrypted tag registered together with ciphertext data in a database, and
generate the search query by using the search keyword, the one or more tag attribute keys included in the user tag key, and the search position information.