| 摘要 |
PROBLEM TO BE SOLVED: To safely calculate elliptic addition.SOLUTION: A multi-party calculation system 1 includes at least three secret calculation devices 2. It is defined that "p" is a prime number larger than 3; Fis a finite field of order "p"; "c" and "d" are constant on the finite field F; cd(1-cd)≠0; E:x+y=c(1+dxy) is an elliptic curve defined on the finite F; and [ ]is a dispersion value of a value " " by secret dispersion on the finite field F. The three secret calculation devices 2 each include an elliptic addition unit 12 which receives a dispersion value [P]=([x],[y]) of a point P=(x,y) on an elliptic curve E and a dispersion value [Q]=([x],[y]) of a point Q=(x,y) on the elliptic curve E, and calculates a dispersion value [R]=([x],[y]) of a point R=(x,y) obtained by elliptic addition of the point P and point Q from the following expression in the figure. |
