Encrypted data analysis device, encrypted data analysis method, and program

Patent metadata

Field	Value
Publication number	US-12189807-B2
Application number	US-202017791833-A
Country	US
Kind code	B2
Filing date	Jan 14, 2020
Priority date	Jan 14, 2020
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

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].

First claim

The invention claimed is:

1. An encrypted data analysis device comprising:
wherein an [x] represents encrypted data of an x,
processing circuitry configured to
sort by [Time Information] and then sort 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] obtained by having encrypted analysis target data of an analysis target data set of a Location ID, a User ID, and Time Information respectively by another device, wherein the analytical target data of the analysis target data set represents unencrypted data that indicate a certain user stays at a certain location at certain time;
generate a [Flow] by extracting the [Location ID] according to the number of hops in a sorted order, the number of hops corresponding to the number of transitions between preset locations, and by further encoding the extracted [Location ID], wherein the [Flow] represents encoded flow information that is generated by without decrypting the encrypted data set group;
storing the [Flow] in a memory device;
determine whether a [User ID] and another [User ID] adjacent to each other are equal, and when not equal, replace a corresponding [Flow] with a [predetermined value that represents invalid] in the memory device;
modifying the [Flow] stored in the memory device as valid data by deleting the [predetermined value that represents invalid] from the [Flow].

2. The encrypted data analysis device according to claim 1 , comprising
processing circuitry configured to
replace a corresponding [Flow] with the [predetermined value that represents invalid] in a case where two pairs of a [Flow] and a [User ID] adjacent to each other are equal.

3. The encrypted data analysis device according to claim 2 , comprising
processing circuitry configured to
generate a [Count] corresponding to a result of tabulating the number of [Flows] whose decryption result is identical.

4. A non-transitory computer readable medium that stores a program for causing a computer to operate as the encrypted data analysis device according to claim 2 .

5. The encrypted data analysis device according to claim 1 , comprising
processing circuitry configured to
generate a [Count] corresponding to a result of tabulating the number of [Flows] whose decryption result is identical.

6. The encrypted data analysis device according to claim 3 , comprising
in a case where the [Count] is less than or equal to a predetermined threshold value or less than a predetermined threshold value, processing circuitry configured to replace a corresponding [Flow] with the [predetermined value that represents invalid] and replace a corresponding [Count] with [0].

7. The encrypted data analysis device according to claim 6 , comprising
in a case where the [Count] is less than or equal to a predetermined threshold value or less than a predetermined threshold value, processing circuitry configured to replace a corresponding [Flow] with the [predetermined value that represents invalid] and replace a corresponding [Count] with [0].

8. A non-transitory computer readable medium that stores a program for causing a computer to operate as the encrypted data analysis device according to claim 6 .

9. A non-transitory computer readable medium that stores a program for causing a computer to operate as the encrypted data analysis device according to claim 5 .

10. A non-transitory computer readable medium that stores a program for causing a computer to operate as the encrypted data analysis device according to claim 1 .

11. An encrypted data analysis method comprising a plurality of steps of a process executed by a processor, the encrypted data analysis method comprising:
wherein an [x] represents encrypted data of an x,
sorting by [Time Information] and then sort 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] obtained by having encrypted analysis target data of an analysis target data set of a Location ID, a User ID, and Time Information respectively by another device, wherein the analytical target data of the analysis target data set represents unencrypted data that indicate certain user stays at a certain location at certain time;
generating a [Flow] by extracting the [Location ID] according to the number of hops in a sorted order, the number of hops corresponding to the number of transitions between preset locations, and by further encoding the extracted [Location ID], wherein the [Flow] represents encoded flow information that is generated by without decrypting the encrypted data set group;
storing the [Flow] in a memory device;
determining whether a [User ID] and another [User ID] adjacent to each other are equal, and when not equal, replacing a corresponding [Flow] with a [predetermined value that represents invalid] in the memory device;
modifying the [Flow] stored in the memory device as valid data by deleting the [predetermined value that represents invalid] from the [Flow];
transmitting the [Flow] over a network; and
decrypting, by said another processor, the [Flow], subsequent to receiving the [Flow] from the encrypted data analysis device over the network.

12. The encrypted data analysis method according to claim 11 , comprising
replacing a corresponding [Flow] with the [predetermined value that represents invalid] in a case where two pairs of a [Flow] and a [User ID] adjacent to each other are equal.

13. The encrypted data analysis method according to claim 12 , comprising
generating a [Count] corresponding to a result of tabulating the number of [Flows] whose decryption result is identical.

14. A non-transitory computer readable medium that stores a program for causing a computer to operate as an encrypted data analysis device comprising a processor executing the encrypted data analysis method according to claim 12 .

15. The encrypted data analysis method according to claim 11 , comprising
generating a [Count] corresponding to a result of tabulating the number of [Flows] whose decryption result is identical.

16. A non-transitory computer readable medium that stores a program for causing a computer to operate as an encrypted data analysis device comprising a processor executing the encrypted data analysis method according to claim 11 .

Assignees

• Nippon Telegraph & Telephone

Inventors

• Kikuchi Ryo
• Takahashi Gen
• Hamada Koki

Classifications

• G06F21/602

  Providing cryptographic facilities or services · CPC title

• G06F2221/2151

  Time stamp · CPC title

• G06F2221/2111

  Location-sensitive, e.g. geographical location, GPS · CPC title

• G09C1/00

  Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system (cryptographic typewriters G09C3/00) · CPC title

• G06F21/6227 Primary

  where protection concerns the structure of data, e.g. records, types, queries · CPC title