公开(公告)号：US20240214213A1

公开(公告)日：2024-06-27

申请号：US18556931

申请日：2021-05-21

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Koki HAMADA ,  Koji CHIDA ,  Masanobu KII ,  Atsunori ICHIKAWA ,  Junichi TOMIDA

IPC: H04L9/32 ,  H04L9/06

CPC classification number: H04L9/3242 ,  H04L9/0618

Abstract: The secure join system includes the first and second information-processing-apparatuses respectively holding first and second data. The second information-processing-apparatus is configured to: create third and fourth vectors in which a hash-value related to a key-value of the first data in a first vector and a ciphertext of the first data corresponding to the key-value in a second vector are rearranged by permutation; and create a fifth vector having a hash-value related to a key-value of the second data. The first information-processing-apparatus is configured to: search for j in which a hash-value of an i-th element of the fifth vector matches a j-th element value of the third vector for each i and create encrypted data in which a ciphertext of a j-th element value of the fourth vector is set when j is found and a ciphertext of a dummy value is set when j is not found.

公开(公告)号：US20240176908A1

公开(公告)日：2024-05-30

申请号：US18552075

申请日：2021-04-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Atsunori ICHIKAWA ,  Koki HAMADA

IPC: G06F21/62 ,  G06F7/58

CPC classification number: G06F21/6245 ,  G06F7/582

Abstract: A secure computation system includes first, second, and third secure-computation-apparatuses each having a tripartite-share of a concealed input vector. The first secure-computation-apparatus converts its tripartite-share into a bipartite-share with the third secure-computation-apparatus; calculates a third vector obtained by subtracting a second permutation of a first vector and a second vector from its permutation of its bipartite-share; and transmits the third vector and the second permutation to the second secure-computation-apparatus. The third secure-computation-apparatus converts its tripartite-share into a bipartite-share with the first secure-computation-apparatus; calculates a fourth vector obtained by adding the first vector to a first permutation of its bipartite-share; transmits the fourth vector to the third secure-computation-apparatus: set the second vector as a bipartite-share with the second secure-computation-apparatus. The second secure-computation-apparatus sets a vector obtained by adding the second permutation of the fourth vector to the third vector, as a bipartite-share with the third secure-computation-apparatus.

公开(公告)号：US20230090900A1

公开(公告)日：2023-03-23

申请号：US17791833

申请日：2020-01-14

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ryo KIKUCHI ,  Gen TAKAHASHI ,  Koki HAMADA

IPC: G06F21/62 ,  G06F21/60

Abstract: The encrypted data analysis device includes a sorting unit that sorts by [Time Information] and then sorts by [User ID] an encrypted data set group including a plurality of encrypted data sets, each of the plurality of encrypted data sets including a [Location ID], the [User ID], and the [Time Information], an encoding unit that generates a [Flow], and encoding the [Location ID] extracted, and an equal sign determination unit that determines whether a [User ID] and another [User ID] adjacent to each other are equal, and when not equal, replaces a corresponding [Flow] with a [predetermined value that represents invalid].

公开(公告)号：US20220335104A1

公开(公告)日：2022-10-20

申请号：US17762740

申请日：2019-10-10

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Koki HAMADA

IPC: G06F17/17

Abstract: An approximate function calculation apparatus includes: a first error upper bound calculating unit which obtains an upper bound of a first error of an approximation of a function f(x) by the function gb(x) in a section [x0, b]; an expansion position calculating unit which obtains an expansion position b′ that represents a maximum b at which the upper bound of the first error; a second error upper bound calculating unit which obtains an upper bound of a second error of an approximation of the function f(x) by a function gb′(x) in a section [b′, x2]; a right end position calculating unit which calculates a right end position x2′ that represents a maximum x2 at which the upper bound of the second error; and a control unit which repeats processing of the respective units with a section [x2′, x1] as the section D.

公开(公告)号：US20220329408A1

公开(公告)日：2022-10-13

申请号：US17634237

申请日：2019-08-14

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ibuki MISHINA ,  Dai IKARASHI ,  Koki HAMADA

IPC: H04L9/06 ,  G06N3/08

Abstract: A calculation of a gradient descent method in secure computing is performed at high speed while maintaining accuracy. A secure gradient descent computation method calculates a gradient descent method while keeping a gradient and a parameter concealed. An initialization unit initializes concealed values [M], [V] of matrices M, V (S11). A gradient calculation unit determines concealed value [G] of a matrix G of a gradient g (S12). A parameter update unit calculates [M] β1 [M]+(1−β1) [G] (S13-1), calculates [V]←β2 [V]+(1−β2) [G]◯[G] (S13-2), calculates [M{circumflex over ( )}]←β{circumflex over ( )}1, t [M] (S13-3), calculates [V{circumflex over ( )}]←β{circumflex over ( )}2, t [V] (S13-4), calculates [G{circumflex over ( )}]←Adam ([V{circumflex over ( )}]) (S13-5), calculates [G{circumflex over ( )}]←[G{circumflex over ( )}]◯[M{circumflex over ( )}] (S13-6), and calculates [W]←[W]−[G{circumflex over ( )}] (S13-7).

公开(公告)号：US20220114110A1

公开(公告)日：2022-04-14

申请号：US17414318

申请日：2020-01-09

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Koki HAMADA ,  Atsunori ICHIKAWA

IPC: G06F12/14 ,  G06F21/62

Abstract: Access to an array is efficiently performed without reveling an accessed position. A storage 10 stores an array of concealed values [x′→] of an array x′→ and an array of addresses a′→ corresponding to respective elements of the array of concealed values [x′→]. A refresh unit 11 determines a concealed value [F] of a random parameter F, an array of concealed values [x→] of an array x→ generated by permutating the array x′→ with random permutation ρ, and an array of public tags b→ calculated from respective elements of the array of addresses a→ with the function TagF. An access unit 12 performs a desired access to an element of the array of concealed values [x→] corresponding to a tag that is calculated from a concealed value [j] of an access position j with the function Tag and the concealed value [F] of the parameter.

公开(公告)号：US20200218833A1

公开(公告)日：2020-07-09

申请号：US16648436

申请日：2018-09-11

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Koki HAMADA

IPC: G06F21/72 ,  G09C1/00

Abstract: Data is efficiently read from a sequence without a read position being revealed. A secure reading apparatus 1 receives a secret text sequence and a secret text of a read position as input, and outputs an element at the read position of the secret text sequence. A vector creating part (12) creates a vector expressing the read position. A compression computing part (13) repeatedly generates a new secret text sequence in which an inner product of a vector based on the secret text sequence and a vector expressing the read position is set as an element. The reading part (14) outputs the new secret text sequence having the number of elements of one as the element at the read position of the secret text sequence.

公开(公告)号：US20190340215A1

公开(公告)日：2019-11-07

申请号：US16311395

申请日：2017-06-30

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION ,  TOHOKU UNIVERSITY

Inventor： Koji CHIDA ,  Satoshi HASEGAWA ,  Koki HAMADA ,  Masao NAGASAKI ,  Kazuharu MISAWA

IPC: G06F17/18 ,  G06F16/901 ,  G16B40/00

Abstract: A Fisher's exact test calculation apparatus includes: a condition storage 1 that has stored therein a condition for determining whether a result of Fisher's exact test corresponding to input is significant or not, the input being frequencies in a summary table; and a calculation unit 2 that obtains the result of Fisher's exact test corresponding to the frequencies in the summary table by inputting the frequencies in the summary table to the condition read from the condition storage 1.

公开(公告)号：US20190228010A1

公开(公告)日：2019-07-25

申请号：US16330212

申请日：2017-09-14

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Dai IKARASHI ,  Naoto KIRIBUCHI ,  Koki HAMADA ,  Gembu MOROHASHI

IPC: G06F16/2455 ,  H04L9/06 ,  H04L9/08 ,  G06F7/76 ,  G06F7/24

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 , 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 ; a second column generating means 140 that generates, for j=a+1, . . . , a+b−1, the j-th column of the table J by using the join-result element sequence and the j−a+1-th column of the table R; and a third column generating means 150 that generates the first column of the table J by using the join-result element sequence and the first column of the table R.

公开(公告)号：US20220318338A1

公开(公告)日：2022-10-06

申请号：US17616192

申请日：2019-06-07

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Koki HAMADA

IPC: G06F17/12 ,  G06F17/16

Abstract: An initialization unit generates secret values of vectors p{right arrow over ( )}0 and r{right arrow over ( )}0 and a value ρ0. A first computation unit generates a secret value of a D-fold value of a vector a{right arrow over ( )}i−1. A second computation unit generates a secret value of a D-fold value of a value γi−1. A third computation unit generates a secret value of a value αi−1. A fourth computation unit generates a secret value of a D-fold value of a vector d{right arrow over ( )}i. A fifth computation unit generates a secret value of a vector x{right arrow over ( )}i. A sixth computation unit the generates a secret value of a vector r{right arrow over ( )}i. A seventh computation unit generates a secret value of a D-fold value of a value ρi. An eighth computation unit generates a secret value of a value βi. A ninth computation unit generates a secret value of a vector p{right arrow over ( )}i.