Confidential computing device, comparison method, comparison program and secret calculation system

摘要

Problem to be solved: to provide a secret computing apparatus for calculating the comparison operation of two integers without and / XOR.The secret computing apparatus compares the first integer a with the second integer B when the first integer a and the second integer B are ring dispersed while 0 is greater than or equal to 2 ^ k (k is an integer greater than 1).The secret calculation apparatus comprises an addition / subtraction circuit section, a bit decomposing circuit section, and a bit extraction circuit section.The addition / subtraction circuit performs predetermined addition / subtraction in ring dispersion using first integer a and second integer B and 2 ^ k, and outputs the addition / subtraction result.The bit decomposing circuit converts the addition and subtraction result into bit dispersion and outputs a bit dispersion result.The bit extraction circuit part extracts the bit dispersion result K + 1 bit and outputs the extracted result.