Secure equijoin system, secure equijoin device, secure equijoin method, and program
US11250004B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 2017 |
| Grant date | Feb 15, 2022 |
| Priority date | — |
| Expiry date | Oct 25, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/46
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A secure equijoin technique of generating one table from two tables while curbing the volume of communications traffic is provided. The technique includes: a first permutation generating means 110 that generates a permutation <σ> from an element sequence which is generated from the first column of a table L and the first column of a table R; a first column generating means 120 that generates, for j=2, . . . , a, by using the permutation <σ>, a prefix sum, and an inverse permutation <σ−1>, the j-th column of a table J from an element sequence which is generated from the to j-th column of the table L; a join-result element sequence generating means 130 that generates a join-result element sequence from an element sequence ([[1]], . . . , [[1]], [[0]], . . . , [[0]], [[−1]], . . . , [[−1]]) by using the permutation <σ>, the prefix sum, and the inverse permutation <σ−1>; a second column generating means 140 that generates, for j=a+1, . . . , a+b−1, the j-th column of the table J by using the join-result element sequence and the j−a+1-th column of the table R; and a third column generating means 150 that generates the first column of the table J by using the join-result element sequence…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.