Encrypted message search method, message transmission/reception system, server, terminal and program
US11223472B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 2017 |
| Grant date | Jan 11, 2022 |
| Priority date | — |
| Expiry date | Aug 1, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L63/0428
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
There is provided an encrypted message search technique making it difficult to, at the time of searching for a message in a state of being encrypted, guess content of the search and a result of the search. There are included: an encrypted search secret key transmission step of a terminal generating an encrypted search secret key from a search secret key generated each time an update interval set in advance elapses and transmitting the encrypted search secret key to a server; a search secret key decryption step of the terminal decrypting the encrypted search secret key acquired from the server to obtain the search secret key; an encrypted message transmission step of the terminal transmitting an index set generated using information related to a message and a newest search secret key, and an encrypted message to the server; a query transmission step of the terminal transmitting a query set generated using a message search character string and the search secret key; and an encrypted message returning step of the server transmitting an encrypted message including elements of an index set corresponding to an element of the query set.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.