Patent ID: 9292258
Filing Date: 2016-03-22
CPC Classification: G06F,H04L

Claim Text:
1. A secure sum-of-product computation method used for performing a sum-of-product computation of data strings A 0 =(a0 0 , . . . , a0 na0-1 ), A 1 =(a1 0 , . . . , a1 na1-1 ) and A 2 =(a2 0 , . . . a2 na2-1 ) and B 0 =(b0 0 , . . . , b0 nb0-1 ), B 1 =(b1 0 , . . . , b1 nb1-1 ) and B 2 =(b2 0 , . . . , b2 nb2-1 ) by cooperative computation by three computation apparatuses, which are a party X, a party Y and a party Z, the sum-of-product computation being expressed as where na0, na1, na2, nb0, nb1 and nb2 represent natural numbers, i0=0, . . . , na0-1, i1=0, . . . , na1-1, i2=0, . . . , na2-1, j0=0, . . . , nb0-1, j1=0, . . . , nb1-1, and j2=0, . . . , nb2-1, and e01 a party-X random number generation step in which the party X generates a number r a party-X first computation step in which the party X computes a value c and transmits the value to the party Z; a party-X second computation step in which the party X receives a number r and outputs the values; a party-Y random number generation step in which the party Y generates a number r a party-Y first computation step in which the party Y computes the value c and transmits the value to the party X; a party-Y second computation step in which the party Y receives the number r and outputs the values; a party-Z random number generation step in which the party Z generates the number r a party-Z first computation step in which the party Z computes the value c and transmits the value to the party Y; and a party-Z second computation step in which the party Z receives the number r and outputs the values.