| 摘要 |
The present invention makes it possible, in encrypted text matching, to avoid information leakage with regard to an original plain text and to ensure security. In the present invention, a system comprises: a means for respectively generating first and second auxiliary data for verifying that a first encrypted text and a second encrypted text match using the Hamming distance of the plain texts, the first encrypted text being at least one data segment, among a plurality of data segments that are obtained by segmenting input data using a segmenting means, that has been encrypted and recorded in a storage device, and the second encrypted text being at least one data segment, among a plurality of data segments obtained by segmenting input data to be collated using a segmenting means, that has been encrypted; and a means for obtaining the difference between the first encrypted text and the second encrypted text and for using the first and the second auxiliary data to determine whether or not the Hamming distance of the plain texts corresponding to the difference between the first encrypted text and the second encrypted text is at or below a predetermined designated value. |
