| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for safely bringing out to outside, file data which is held in a computer.SOLUTION: The method includes: a step of dividing the file data into a plurality of fragmented files by using a threshold secret sharing method in a computer; a step of transmitting a plurality of divided fragmented files to a plurality of net storage services to hold the files; and a step of obtaining at least two of the fragmented files held in the net storage services in a computer using the file data, to restore the original file data. |
