Abstract: A secure joining system is a secure joining system including a plurality of secure computing apparatuses. The plurality of secure computing apparatuses include a first vector joining unit, a first permutation calculation unit, a first vector generation unit, a second vector joining unit, a first permutation application unit, a second vector generation unit, a first inverse permutation application unit, a first vector extraction unit, a second permutation application unit, a third vector generation unit, a second inverse permutation application unit, a second vector extraction unit, a modified second table generation unit, a third permutation application unit, a fourth vector generation unit, a shifting unit, a third inverse permutation application unit, a bit inversion unit, a third vector extraction unit, a modified first table generation unit, a first table joining unit, and a first table formatting unit.

Abstract: A relay device transfers a plurality of original data fragments corresponding to a plurality of secret sharing values of original data to a plurality of secure computation devices, transfers, to each of the secure computation devices, a request to send a result fragment based on a secure computation result corresponding to any one of the original data fragments, and transfers the result fragment. The relay device controls timing with which the original data fragments are transferred and timing with which the request to send is transferred.

Abstract: A secure equijoin technique of generating one table from two tables while curbing the volume of communications traffic is provided. The technique includes: a first permutation generating means 110 that generates a permutation <?> from an element sequence which is generated from the first column of a table L and the first column of a table R; a first column generating means 120 that generates, for j=2, . . . , a, by using the permutation <?>, a prefix sum, and an inverse permutation <??1>, the j-th column of a table J from an element sequence which is generated from the to j-th column of the table L; a join-result element sequence generating means 130 that generates a join-result element sequence from an element sequence ([[1]], . . . , [[1]], [[0]], . . . , [[0]], [[?1]], . . . , [[?1]]) by using the permutation <?>, the prefix sum, and the inverse permutation <??1>; a second column generating means 140 that generates, for j=a+1, . . .

Abstract: A secure joining system is a secure joining system including a plurality of secure computing apparatuses. The plurality of secure computing apparatuses include a first vector joining unit, a first permutation calculation unit, a first vector generation unit, a second vector joining unit, a first permutation application unit, a second vector generation unit, a first inverse permutation application unit, a first vector extraction unit, a second permutation application unit, a third vector generation unit, a second inverse permutation application unit, a second vector extraction unit, a modified second table generation unit, a third permutation application unit, a fourth vector generation unit, a shifting unit, a third inverse permutation application unit, a bit inversion unit, a third vector extraction unit, a modified first table generation unit, a first table joining unit, and a first table formatting unit.

Abstract: A database system comprises a determining part 13 determining whether or not to conceal information to be registered in a database, a terminal device 1 that, if the determining part 13 determines that the information is to be concealed, generates N information fragments by secret-sharing the information and sends the N information fragments to a system management device 2, where N is a predetermined positive integer, the system management device 2 sending the N information fragments received from the terminal device 1 to N different database devices 3, and N database devices 3 each storing one of N information fragments received from the system management device 2.

Abstract: A vector generation unit generates a vector xn so that xn[i]?xn[j] if kn[i]=kn[j] at i?j. A set generation unit generates a set Bn,j so that individual elements correspond to combinations of the N?1 pieces of elements, which are individually selected from sets M0, . . . , MN?1 other than a set Mn, and xn[j] and the elements for all of the combinations are included. A matrix generation unit generates a matrix Tn? so that the matrix Tn? includes rows identical to Tn[j] in the number equal to the number of elements of the set Bn,j. A key generation unit generates a vector kn? so that elements of the matrix Tn? which correspond to a row identical to Tn[j] correspond to combinations of kn[j] and elements of the set Bn,j and further, the elements of the set Bn,j are different from each other when there are a plurality of rows identical to Tn[j].

Abstract: A secure equijoin technique of generating one table from two tables while curbing the volume of communications traffic is provided. The technique includes: a first permutation generating means 110 that generates a permutation <?> from an element sequence which is generated from the first column of a table L and the first column of a table R; a first column generating means 120 that generates, for j=2, . . . , a, by using the permutation <?>, a prefix sum, and an inverse permutation <??1>, the j-th column of a table J from an element sequence which is generated from the to j-th column of the table L; a join-result element sequence generating means 130 that generates a join-result element sequence from an element sequence ([[1]], . . . , [[1]], [[0]], . . . , [[0]], [[?1]], . . . , [[?1]]) by using the permutation <?>, the prefix sum, and the inverse permutation <??1 >; a second column generating means 140 that generates, for j=a+1, . . .

Abstract: Determination as to whether a nondecreasing sequence exists or not is efficiently made. A sorting part sorts elements of a set Pi in ascending order to generate vectors ti,i+1 and bi,i+1. A merging part generates vectors t0,m and b0,m by repeating the process of merging vectors (ti,j, bi,j) and (tj,k, bj,k) to generate (ti,k, bi,k). A stable-sorting part generates a vector e by coupling and stably sorting vectors bi,j and tj,k. A searching part searches for sets of (?, x, y) in which e[?] is bi,j[x] and e[?+1] is tj,k[y] and generates a set X including all x and a set Y including all y. An extracting part sorts ti,j[x] (x?X) in ascending order to generate a vector ti,k and sorts bj,k[y] (y?Y) in ascending order to generate a vector bi,k. If the length of a vector t0,m is 0, a determining part outputs a result of determination that indicates the absence of a nondecreasing sequence.

Abstract: The positions in a text in which partial character strings in a pattern appear are efficiently detected. A partial-character-string position detecting device 1 takes inputs of a secret text [t] of a text t, a secrete text <p> of a pattern p, a secret text <c> of a vector c, and a secret text <E> of a matrix E and outputs a secret text <H> of a matrix H. A first matrix generating part 20 generates a secret text <F> of a matrix F, in which F[i][j]=E[i][j+i mod n+1] (where it is assumed that E[i][n]=¬c[i]). A second matrix generating part 30 generates a secret text <F?> of a matrix F?, in which F[i][j]=1 is set if c[i]=0 or if c[i]=1 and F[k][j]=1 for every k that is successively c[k]=1, otherwise F[i][j]=0 is set, where k=i, . . . , n?1. A third matrix generating part 40 computes <H[i][j]>=<F[i][j?i mod n+1]>?<c[i]>?¬<c[i?1]> to generate the secrete text <H>.

Abstract: Data processing is performed while personal information is kept concealed. A registrant terminal splits a registration input password and allocates the split pieces to secure computation servers. The secure computation servers verify whether the password matches. The registrant terminal splits target data and allocates the data shared values to the secure computation servers. The secure computation servers store the data shared values. A user terminal splits a utilization input password and allocates the split pieces to the secure computation servers. The secure computation servers verify whether the password matches. The user terminal sends a data processing request to the secure computation servers. The secure computation servers execute secure computation of the data shared values to generate processing result shared values. The user terminal recovers the processing result from the processing result shared values.

Abstract: A vector generation unit generates a vector x so that xn[i]?xn[j] if kn[i]=k[j] at i?j. A set generation unit generates a set Bn,j so that individual elements correspond to combinations of the N?1 pieces of elements, which are individually selected from sets M0, . . . , MN?1 other than a set Mn, and xn[j] and the elements for all of the combinations are included. A matrix generation unit generates a matrix Tn? so that the matrix Tn? includes rows identical to Tn[j] in the number equal to the number of elements of the set Bn,j. A key generation unit generates a vector kn? so that elements of the matrix Tn? which correspond to a row identical to Tn[j] correspond to combinations of kn[j] and elements of the set Bn,j and further, the elements of the set Bn,j are different from each other when there are a plurality of rows identical to Tn[j].

Abstract: A database system comprises a determining part 13 determining whether or not to conceal information to be registered in a database, a terminal device 1 that, if the determining part 13 determines that the information is to be concealed, generates N information fragments by secret-sharing the information and sends the N information fragments to a system management device 2, where N is a predetermined positive integer, the system management device 2 sending the N information fragments received from the terminal device 1 to N different database devices 3, and N database devices 3 each storing one of N information fragments received from the system management device 2.

Abstract: A relay device transfers a plurality of original data fragments corresponding to a plurality of secret sharing values of original data to a plurality of secure computation devices, transfers, to each of the secure computation devices, a request to send a result fragment based on a secure computation result corresponding to any one of the original data fragments, and transfers the result fragment. The relay device controls timing with which the original data fragments are transferred and timing with which the request to send is transferred.

Abstract: Determination as to whether a nondecreasing sequence exists or not is efficiently made. A sorting part sorts elements of a set Pi in ascending order to generate vectors ti,i+1 and A merging part generates vectors t0,m and b0,m by repeating the process of merging vectors (ti,j, bi,j) and (ti,k, bi,k) to generate (ti,k, bi,k). A stable-sorting part generates a vector e by coupling and stably sorting vectors bi,j and ti,k. A searching part searches for sets of (?, x, y) in which e[?] is bi j[x] and e[?+1] is ti,k[y] and generates a set ? including all x and a set Y including all y. An extracting part sorts ti,j[x] (x?X) in ascending order to generate a vector ti,k and sorts bj,k[y] (y?Y) in ascending order to generate a vector bi,k. If the length of a vector t0,m is 0, a determining part outputs a result of determination that indicates the absence of a nondecreasing sequence.

Abstract: The positions in a text in which partial character strings in a pattern appear are efficiently detected. A partial-character-string position detecting device 1 takes inputs of a secret text [t] of a text t, a secrete text <p> of a pattern p, a secret text <c> of a vector c, and a secret text <E> of a matrix E and outputs a secret text <H> of a matrix H. A first matrix generating part 20 generates a secret text <F> of a matrix F, in which F[i][j]=E[i][j+i mod n+1] (where it is assumed that E[i][n]=c[i]). A second matrix generating part 30 generates a secret text <F?> of a matrix F?, in which F[i][j]=1 is set if c[i]=0 or if c[i]=1 and F[k][j]=1 for every k that is successively c[k]=1, otherwise F[i][j]=0 is set, where k=i, . . . , n?1. A third matrix generating part 40 computes <H[i][j]>=<F[i][j?i mod n+1]><c[i]>> to generate the secrete text <H>.

Abstract: Data processing is performed while personal information is kept concealed. A registrant terminal splits a registration input password and allocates the split pieces to secure computation servers. The secure computation servers verify whether the password matches. The registrant terminal splits target data and allocates the data shared values to the secure computation servers. The secure computation servers store the data shared values. A user terminal splits a utilization input password and allocates the split pieces to the secure computation servers. The secure computation servers verify whether the password matches. The user terminal sends a data processing request to the secure computation servers. The secure computation servers execute secure computation of the data shared values to generate processing result shared values. The user terminal recovers the processing result from the processing result shared values.