Nippon Telegraph and Telephone Corporation

Ntt Corporation

Hiroki Sudo

Dai Ikarashi

Ryo Kikuchi

Koki Hamada

Atsunori Ichikawa

Ibuki Mishina

By using [x], . . . , [x], . . . , [x], . . . , [x] obtained by concealing L sets X={x, . . . , x}, . . . , X={x, . . . , x}, [c], . . . , [c] obtained by concealing the number cof elements representing kamong x, . . . , x, . . . , x, . . . , xfor p=0, . . . , m−1 are obtained, [eq], . . . , [eq] obtained by concealing eq=T when cis L and eq=F when cis not L for p=0, . . . , m−1 are obtained, and a data structure including [k] and [eq] associated with each other is output as a concealed operation result of a product set of X, . . . , X.

Secure computation apparatus, secure computation system, secure computation method, and program

A secure computation deviceof a secure computation system according to an aspect of this invention includes a first calculation unit, a second calculation unit, a third calculation unit, a fourth calculation unit, a fifth calculation unit, a sixth calculation unit, a seventh calculation unit, and an output unit. By calculation being performed in cooperation of these, a group by count operation can be performed on a table to which a flag is added.

Secret calculation system, apparatus, method and program

A concealed operation result indicating concealed information of an Intersect operation result of X and Y is obtained while X={{x, . . . , x}} and Y={{y, . . . , y}} are concealed. A secure computation device obtains a sequence ([s], [M]) including [s] including n [B] and m [B] and [M] including [x], . . . , [x] and [y], . . . , [y], performs stable sorting on the sequence ([s], [M]) according to an order relationship of content represented by each of the elements M, . . . , Mto obtain a sequence ([s'], [M′]), obtain [eq] where eq=T when M′=M′and eq=F otherwise and [seq] where seq=T when s′=s′and seq=F otherwise, obtain [f] where f=Dwhen eq=T and seq=F and f=Dotherwise, and outputs [f] and [M′]. Where, [α] is concealed information of α.

The present invention provides techniques to calculate the number of surviving and the number of deaths while still concealing survival time data. The present invention includes: a group data position calculation means configured to calculate a share [[g]] of a sequence gand a share [[g]] of a sequence grepresented by predetermined equations from a share [[g]] of a sequence g of values of group of survival time data included in a survival time data set D; a group data number calculation means configured to calculate a share [[s]] and a share [[s]] from a share [[t]] of a sequence t of values of time of survival time data included in the survival time data set D, the share [[g]], and the share [[g]], by [[s]]=GroupSum ([[g]], [[t]]), [[s]]=GroupSum ([[g]], [[t]]); and a survival number calculation means.

Growing community of inventors

Musashino, Japan

Hiroki Sudo