Management device, control method for management device, and program

Abstract

A management device for managing an electronic signature for electronic content is provided with: an acquisition unit for acquiring an instruction to perform a signature; a signature generation unit that generates an electronic signature; an assigning unit that assigns the electronic content to the electronic signature; an electronic certificate generation unit that generates an electronic certificate; an electronic certificate information storage unit that executes a process for storing the electronic certificate information in each of the plurality of ledger systems; an answer acquisition unit that acquires a plurality of answers to the requested electronic certificate information; a sum value calculation unit that calculates a sum value for each of the same answers by summing coefficients associated with the ledger system for each of the same answers included in the plurality of answers; a specifying unit that specifies the one answer as an answer that matches the electronic certificate information on the basis of the summation value; and an output unit that outputs one answer.

Description

Technical Field

[0001] This disclosure relates to a management device, a method for controlling the management device, and a procedure for doing so. Background Technology

[0002] In the past, electronic signatures have been used to ensure the authenticity of electronic content data such as electronic documents. For example, Patent Document 1 discloses an electronic signature management system for electronically signing data of the signatory. In addition, Patent Document 2, as a method for identity authentication using blockchain as a distributed ledger system, proposes a method for storing the hash value of the identity information of the person who has implemented electronic signature in the blockchain.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-067807

[0006] Patent Document 2: Japanese Patent Application Publication No. 2024-077561

[0007] It has been considered to store certificates used to prove matters related to electronic signatures (electronic certificates) in ledger systems such as blockchains, but since the information stored in the ledger system itself may be tampered with, it is desirable to further improve the reliability of electronic signatures. Summary of the Invention

[0008] Therefore, the present invention was made in view of the above-mentioned prior circumstances, and its purpose is to improve the reliability of electronic signatures.

[0009] The management apparatus according to embodiments of the present invention is a management apparatus for managing electronic signatures on electronic content, comprising: an acquisition unit for acquiring an instruction to sign electronic content; an signature generation unit for generating an electronic signature in response to the instruction; an assignment unit for assigning the generated electronic signature to the electronic content; an electronic certificate generation unit for generating an electronic certificate associated with the electronic signature; an electronic certificate information storage unit for performing processing for storing electronic certificate information, which is information contained in the electronic certificate, in each of a plurality of ledger systems; a response acquisition unit for acquiring a plurality of responses to the request, which are outputs from each of the plurality of ledger systems, by sending a request to each of the plurality of ledger systems to store the electronic certificate information in each ledger system; a total value calculation unit for calculating a total value for each identical response included in the plurality of responses by summing coefficients associated with the ledger system that output the response; a determination unit for determining one of the plurality of responses as the response consistent with the electronic certificate information based on the total value; and an output unit for outputting a response.

[0010] Therefore, electronic certificate information, which is at least part of an electronic certificate associated with electronic signature, is stored in each of multiple ledger systems. Then, responses to requests for electronic certificate information are retrieved from each of these ledger systems. For each identical response, a total value is calculated by summing coefficients associated with the ledger system that output the response. Based on this total value, one of the responses is identified as the one consistent with the electronic certificate information and is output. Thus, the possibility of tampering with electronic certificate information is reduced, thereby improving the reliability of electronic signature.

[0011] Invention Effects

[0012] According to the present invention, the reliability of electronic signatures can be improved. Attached Figure Description

[0013] Figure 1 This is a schematic diagram showing the outline of the electronic signature management system 100 using the management device 1 involved in the implementation.

[0014] Figure 2 It is a schematic diagram representing an electronic document D labeled with the electronic signature S generated by the management device 1 involved in the implementation method.

[0015] Figure 3 This is a block diagram illustrating the configuration of the management device 1 according to the implementation method.

[0016] Figure 4 This is a schematic diagram illustrating an example of the data structure of an electronic certificate involved in the implementation method.

[0017] Figure 5 This is a schematic diagram illustrating an example of the data construction of a ledger system table in an implementation method.

[0018] Figure 6 This is a block diagram illustrating the configuration of the user terminal 4 involved in the implementation method.

[0019] Figure 7 This is a timing diagram illustrating an example of the work processes performed by the electronic signature management system 100 according to the implementation method, such as generating electronic signatures and electronic certificates.

[0020] Figure 8 This is a flowchart illustrating an example of the query processing of electronic certificate information performed by the management device 1 involved in the implementation.

[0021] Explanation of reference numerals in the attached figures

[0022] 1…Management device, 2…Electronic content database, 3A, 3B, 3C…Ledger system, 4, 4A, 4B, 4C, 4D…User terminal, 11…Document management department, 12…Instruction acquisition department, 13…User information acquisition department, 14…Signature generation department, 15…Assignment department, 16…Electronic certificate generation department, 17…Electronic certificate information storage department, 18…Response acquisition department, 19…Total value calculation department, 20…Determination department, 21…Transfer and receive department, 41…Camera department, 42…Identifier acquisition department, 43…Hash value calculation department, 44…Consistency confirmation department, 45…Output department, 46…Operation receiving department, 47…Transfer and receive department, N…Communication network, S…Electronic signature, D…Electronic content, D0, D1, D2…Electronic document. Detailed Implementation

[0023] Suitable embodiments of the present invention will be described with reference to the accompanying drawings. (Furthermore, in each drawing, portions labeled with the same reference numerals have the same or identical configuration.)

[0024] (1) Summary

[0025] Figure 1 This is a schematic diagram showing the outline of the electronic signature management system 100 using the management device 1 involved in the implementation.

[0026] like Figure 1 As shown, the electronic signature management system 100 includes, for example, a management device 1, an electronic content database 2, multiple ledger systems 3, and multiple user terminals 4. Figure 1In the example shown, the ledger system 3 includes a first ledger system 3A, a second ledger system 3B, and a third ledger system 3C. Furthermore, the ledger system 3 involved in the implementation is not limited to three; it may include two or more ledger systems 3. The management device 1 is connected to the electronic content database 2 and the ledger system 3 respectively in a manner capable of managing (storing, deleting, modifying, etc.) information. Additionally, the management device 1 is connected to multiple user terminals 4 via a communication network N such as the Internet, enabling them to send and receive information.

[0027] Management device 1 is, for example, a computer (information processing device) such as a server, having a processing unit such as a CPU and a storage element such as a memory. Management device 1 is a device for generating an electronic signature S for electronic content D such as contracts for users. Electronic content D is stored, for example, in an electronic content database 2. That is, management device 1 is a device with the function of generating an electronic signature S for electronic content D to be given to users. Management device 1 can, for example, generate electronic content D indicating consent to electronic content D by visually recognizing the electronic signature S.

[0028] Furthermore, in the following embodiments, "electronic content" may include both "electronic documents" and "electronic images." "Electronic content" can refer to any document such as a contract, quotation, application, order list, delivery note, payment request, receipt, invoice, meeting minutes, approved payment requests, application forms, signature books, etc., and may also include documents generated electronically. Furthermore, "electronic images" can be still images or animations (videos) composed of multiple still images sequentially in time. Animations may be combined with sound. Additionally, "electronic signature" may include the process of electronically stamping electronic content D onto a paper contract, etc. Moreover, "electronic certificate" can be a certificate used to certify matters related to electronic signature; for example, it may also include an electromagnetic record created to prove that the matter for which the user has made an electronic signature is related to that user.

[0029] Figure 2 This is a schematic diagram of an electronic document D labeled with the electronic signature S generated by the management device 1 according to the implementation method. In particular, the management device 1, as... Figure 2 As shown, an electronic signature S that is visually recognizable relative to the electronic document D can be assigned. For example, the management device 1 can visually assign an electronic signature S corresponding to each user. The management device 1 can, for example, assign an electronic signature S displayed as a QR code (registered trademark) to the electronic content D. Furthermore, when assigning an electronic signature S to an electronic image that is part of the electronic content, the management device 1 can overlay the electronic signature S onto a portion of at least any still image contained in the electronic image, or it can assign an electronic signature S to the metadata contained in the electronic image.

[0030] like Figure 1 As shown, management device 1 is connected to ledger systems 3 (first ledger system 3A, second ledger system 3B, and third ledger system 3C). Management device 1 creates electronic certificates with electronic content D assigned an electronic signature S. Management device 1 stores at least a portion (electronic certificate information) of the created electronic certificate with electronic content D in the first ledger system 3A, second ledger system 3B, and third ledger system 3C respectively. Each ledger system 3 can be a distributed ledger system. Ledger system 3 can, for example, be configured as multiple node computers (nodes) including a blockchain. The form of the blockchain is not particularly limited; for example, it can be configured as a private blockchain of any type, such as public, consortium, or private. Management device 1 stores the electronic certificate in the first ledger system 3A, second ledger system 3B, and third ledger system 3C, which are configured as such a blockchain.

[0031] The management device 1 performs query processing (query processing) on ​​multiple ledger systems 3 of the electronic signature management system 100 within a predetermined time sequence to query desired electronic certificate information. The management device 1 requests electronic certificate information stored in each of the multiple ledger systems 3 and obtains responses from each ledger system 3 to the requests. Here, in at least one of the ledger systems 3, if electronic certificate information has been tampered with, the multiple responses obtained from the multiple ledger systems 3 may contain multiple different responses. However, in the management device 1 according to the embodiment, since the electronic certificate information is managed by multiple ledger systems 3, the authenticity of the electronic certificate information can be guaranteed. That is, for each identical response contained in the responses obtained from each ledger system 3, the management device 1 calculates a total value for each identical response contained in the multiple responses by summing the coefficients associated with the ledger system that output the response. Based on the total value, the management device 1 determines one of the multiple responses as the response consistent with the electronic certificate information and outputs that response. Thus, in the electronic signature management system 100 described in this implementation, electronic certificate information is first stored in multiple ledger systems 3. At predetermined intervals, the management device 1 queries the electronic certificate information in the multiple ledger systems 3 to determine and output the authentic electronic certificate information. This reduces the possibility of tampering with the electronic certificate information, thereby improving the reliability of electronic signatures.

[0032] like Figure 1As shown, the user terminal 4 is configured as a device different from the management device 1. The user terminal 4 is, for example, a computer (information processing device) such as a smartphone, tablet computer, or personal computer with a camera, and has a processing unit such as a CPU and a storage element such as a memory. Based on the electronic signature S generated by the management device 1, the user terminal 4 retrieves information contained in an electronic certificate stored in the ledger system 3 via the management device 1, and performs processing to verify the authenticity of the electronic content D based on the retrieved information. Furthermore, the user terminal 4 performs various information display processing based on the information contained in the retrieved electronic certificate. In particular, the user terminal 4 displays a URL for determining the storage area where the electronic content D is stored in the electronic content database 2. When the user selects this URL, the user terminal 4 retrieves the electronic content D from the electronic content database 2 and displays the electronic content D. Thus, the content of the electronic content D can be verified while ensuring its authenticity. Moreover, since the content of the electronic content D can be verified from the electronic signature S, the user can maintain evidentiary value (based on information on the electronic certificate) even if they keep a physical document containing the electronic content D, such as a printed copy of the electronic content D.

[0033] (2) Composition

[0034] (2-1) Management device 1

[0035] Figure 3 This is a block diagram showing the configuration of the management device 1 according to the embodiment. The management device 1 includes a document management unit 11, an instruction acquisition unit 12, a user information acquisition unit 13, a signature generation unit 14, an assignment unit 15, an electronic certificate generation unit 16, an electronic certificate information storage unit 17, a response acquisition unit 18, a total value calculation unit 19, a determination unit 20, and a transceiver unit 21. These various functional units are implemented by a processing unit such as a CPU included in the management device 1.

[0036] The document management unit 11 is implemented, for example, by operating a CPU. The document management unit 11 performs tasks such as generating, acquiring, modifying, and storing electronic content that becomes the object of electronic signature on storage devices. The document management unit 11 acquires electronic content D, for example, from the electronic content database 2 or the user terminal 4. Electronic content D can be electronic data generated by document generation software or image generation software, or data from scanned printed materials such as paper. Furthermore, the document management unit 11 can also generate / modify electronic content based on instructions obtained from the user terminal 4. Additionally, the document management unit 11 can store electronic content in the electronic content database 2.

[0037] The instruction acquisition unit 12 acquires an instruction (signature instruction) for the acquired electronic content D, which is to be signed. For example, the instruction acquisition unit 12 acquires the signature instruction from the user terminal 4.

[0038] The user information acquisition unit 13 acquires user information as user information. Furthermore, in this embodiment, the user information acquisition unit 13 acquires the user ID and username of the previously issued user. Here, the user information acquisition unit 13 acquires the user IDs and usernames of each sign-up user (user) as user information. Furthermore, in this embodiment, the user information acquisition unit 13 acquires user information from the user terminal 4, etc., when generating the electronic signature S. The user information may also include any information inherent in the user managed by the user management system.

[0039] The signature generation unit 14 generates an electronic signature S that encodes the electronic certificate identifier, serving as the identifier of the electronic certificate. Alternatively, the signature generation unit 14 may include a unique string in the electronic certificate identifier. This string can be unique for each electronic signature S. The electronic certificate identifier is generated (numbered), for example, by assigning the electronic signature S to the electronic content D.

[0040] The assignment unit 15 assigns the generated electronic signature S to the electronic content D. The assignment unit 15 can, for example, assign the electronic signature S to the electronic content D in a visually identifiable manner. Therefore, it is easy to identify that the electronic content D has been assigned the electronic signature S. Figure 2 As shown, the assignment unit 15 can, for example, assign the electronic signature S generated in a side-by-side position to the legal entity name and the representative's name, which are information about the user recorded in the electronic content D. The assignment unit 15 can, for example, assign the electronic signature S at a position clearly defined in the electronic content D that corresponds to the electronic signature S containing the user's information. In an embodiment, the assignment unit 15 can write the user's name, included in the acquired user information, into the electronic signature S. Figure 2 As shown, the assigning unit 15, for example, writes the user's electronic signature S (QR code) below the display surface of the electronic content D (electronic document). Thus, it is possible to clearly identify which user's electronic signature S belongs to. Furthermore, since the encoded electronic signature S can be written along with the signature, the code can be processed like a photocopy, resulting in a visual effect similar to a stamp on paper.

[0041] The electronic certificate generation department 16 generates various electronic certificates associated with the electronic signature S. These electronic certificates are, for example, stored in the ledger system 3.

[0042] Figure 4 This is a schematic diagram illustrating an example of the data construction involved in the implementation method. For example... Figure 4Each row shown represents an electronic certificate. These electronic certificates are appended to the ledger system one by one, for example, each time an electronic signature is assigned to electronic content.

[0043] Electronic certificates may include, for example, the issuer's name, issue number, issue date and time, expiry date of validity, series ID, sub-number, user ID, user's organization, user's position, user's name, signed content, original hash value, hash value before signing, hash value after signing, URL for public access to electronic content, and password.

[0044] The issuer name is the name of the issuer of the electronic certificate, or, for example, the name of the administrator of management device 1. The issuance number is the identifier of the electronic certificate issued through management device 1 (an identifier used to identify the electronic certificate). The issuance date and time are the date and time the electronic certificate was issued, or it can be the time information of the signature. The issuance date and time is an example of ranking information indicating the ranking of the electronic signature (each time an electronic signature is assigned, it indicates that the electronic signature is a ranking among a series of electronic signatures). The expiration date is the date on which the validity period of the electronic certificate ends.

[0045] A series ID is an example of system identification information used to identify electronic content D. The series ID remains unchanged even when one or more electronic signatures S are assigned to electronic content D, and can be considered inherent identification information about the system (of electronic content D). In other words, the series ID is identification information assigned relative to the content represented by electronic content D (which may also include modified content). Therefore, when electronic signatures S are continuously assigned to electronic content D, it is possible to manage electronic content D or a series of electronic signatures S as a series, and to confirm whether a particular electronic signature S within a series of electronic signatures S is the most recent, and whether the electronic signature marked on the held electronic content D is the most recent, etc.

[0046] The sub-number is an example of ranking information indicating the ranking of electronic signature S (indicating that each time an electronic signature S is assigned, it represents a ranking among a series of electronic signatures S). In Figure 4 In the example shown, natural numbers such as 1, 2, and 3 are used as semicolons, but if the ranking can be displayed, semicolons (ranking information) can be arbitrarily constructed using symbols or other markings.

[0047] User ID is the user's identification information. User Organization indicates the organization to which the user belongs. User Position indicates the user's position within that organization. User Name is the user's name (or the name of the person in charge within the company).

[0048] The signature content can be information attached to the electronic signature S, or it can be data in text form that the user arbitrarily enters. The signature content can, for example, indicate the intention of the user attaching the electronic signature, or, if the electronic content related to the signature has been modified, it can indicate either the modification itself or the modified content. Therefore, by verifying the electronic certificate, it is possible to confirm whether there was any intention from the user regarding the electronic signature, whether there were any modifications to the electronic content, and its content itself.

[0049] The original hash value, the pre-signature hash value, and the post-signature hash value are used, for example, in the consistency verification process related to electronic content D. The consistency verification process will be described later. The original hash value is the hash value of electronic content D (the original) without any electronic signature. The pre-signature hash value is the hash value of electronic content D (including electronic content D with electronic signatures ranked higher than S) before the latest electronic signature S was assigned. The post-signature hash value is the hash value of electronic content D with the latest electronic signature S assigned.

[0050] The URL for public access to electronic content can be a URL used to identify the storage area where electronic content D is stored (e.g., the URL of electronic content D in electronic content database 2). An expiration period can also be set in the URL for public access to electronic content. The password can be either a password required to access the URL for public access to electronic content D, or it can be arbitrary or assigned by the system.

[0051] Furthermore, the aforementioned electronic certificate is merely an example. The electronic certificate in the implementation may not include any of the items mentioned above, or it may include items other than those mentioned above.

[0052] The electronic certificate information storage unit 17 stores at least a portion (electronic certificate information) of the generated electronic certificate in the ledger system 3 (first ledger system 3A, second ledger system 3B, and third ledger system 3C). The electronic certificate information, which is at least a portion of the electronic certificate information, may include, for example, […]. Figure 4 At least a portion of the information shown.

[0053] The response acquisition unit 18 retrieves electronic certificate information stored in each ledger system 3. Specifically, the response acquisition unit 18 sends a request to each ledger system 3 requesting electronic certificate information stored in each ledger system 3. After receiving the request for electronic certificate information from the management device 1, the ledger system 3 responds to the request by outputting the electronic certificate information stored in the ledger system 3 and sending the output electronic certificate information as a response to the request to the management device 1. The response acquisition unit 18 retrieves this response from each ledger system 3. The timing of the response acquisition process performed by the response acquisition unit 18 can be arbitrary, for example, when a query request for electronic certificate information is received from a user terminal 4, or when a new electronic signature for an electronic document is generated.

[0054] The total value calculation unit 19 calculates the total value of each identical answer included in the multiple answers obtained by the answer acquisition unit 18 from the multiple ledger systems 3 by summing the coefficients associated with the ledger system 3 that output the answer. That is, the total value can be the sum of the coefficients of at least one ledger system 3 that output the same answer. Furthermore, the total value is a value calculated in association with the answer to the electronic certificate information, and can be considered a score used to select authentic electronic certificate information that has not been tampered with.

[0055] For example, the determining unit 20 determines one of the multiple responses obtained from each ledger system 3 as the response that matches the electronic certificate information, based on the total value calculated by the total value calculation unit 19. Alternatively, the determining unit 20 may also determine the response with the highest total value among the responses obtained from the multiple ledger systems 3 as the response that matches the electronic certificate information.

[0056] The transceiver unit 21 exchanges various types of information with the user terminal 4. For example, the transceiver unit 21 receives an instruction for signature on electronic content D from the user terminal 4. Additionally, the transceiver unit 21 sends electronic content D (including an electronic signature S) to the user terminal 4. Furthermore, the transceiver unit 21 outputs a response, as an example of an output unit, which is determined by the determination unit 20 to be consistent with the information in the electronic certificate. Here, the processing of outputting the response may include, for example, sending the response to other external devices such as the user terminal 4, or displaying the response on any display device.

[0057] The components included in management device 1 can be implemented separately through hardware, software, or a combination thereof. Here, implementation through software means implementation by reading and executing a program on a computer. The program is stored using various types of non-transitory computer-readable medium and can be supplied to a computer. Non-transitory computer-readable medium includes various types of tangible storage medium. Examples of non-transitory computer-readable medium include magnetic storage media (e.g., floppy disks, magnetic tapes, hard disk drives), optical-magnetic storage media (e.g., magneto-optical disks), CD-ROM (Read Only Memory), CD-R, CD-R / W, and semiconductor memory (e.g., mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)). Furthermore, the display program can also be supplied to the computer through various types of transient computer-readable medium. Examples of transient computer-readable medium include electrical signals, optical signals, and electromagnetic waves. Temporary computer-readable media can deliver programs to a computer via wired or wireless communication lines such as electrical wires and optical fibers.

[0058] Figure 5 This is a schematic diagram illustrating an example of the data structure of the ledger system table according to the implementation method. The ledger system table may, for example, be stored in a storage unit accessible to the management device 1, such as a storage unit included in the management device 1. The ledger system table may include information related to each ledger system 3 included in the electronic signature management system 100. Figure 5 In the example shown, the ledger system table contains coefficients and characteristic information for each ledger system 3.

[0059] The coefficient is a value associated with each ledger system 3, serving as the basis for calculating the total value, for example, during the query processing of electronic certificate information. In other words, the coefficient can be a value representing the probability or likelihood that the information stored as electronic certificate information in ledger system 3 is consistent with the actual electronic certificate information.

[0060] The ledger system table may include characteristic information representing the characteristics of each ledger system 3. Characteristic information may, for example, be information indicating the type of ledger system 3. The type of ledger system 3 may be, for example, a distinction between distributed and non-distributed, or, in the case of distributed systems, the type (public, consortium, and private, etc.). Furthermore, characteristic information may include, for example, the algorithm type. The algorithm type indicates the type of algorithm (consensus algorithm, etc.) used by the ledger system 3 for storing information. Specifically, the algorithm type may include blockchain, Ethereum, and other algorithms. Additionally, characteristic information may also include, for example, the number of nodes. The number of nodes may be the number of nodes constituting the ledger system 3. Furthermore, Figure 5 The characteristic information shown is just one example; the ledger system table can also contain any characteristic information representing the characteristics of ledger system 3.

[0061] Management device 1 can also calculate and update coefficients based on characteristic information representing the characteristics of each ledger system 3. Management device 1 can also calculate coefficients such that the coefficients of all ledger systems 3 are equal. In this case, essentially a majority vote among multiple ledger systems 3 determines an answer consistent with the electronic certificate information. Alternatively, management device 1 can, for example, calculate coefficients such that the less likely the characteristic information of a ledger system 3 is to be tampered with, the larger its coefficient. Specifically, for example, the coefficient can be larger if the ledger system 3 is distributed compared to a non-distributed system. Furthermore, the type of distributed ledger system 3 can be adjusted to increase the coefficient, for example, in the order of public, consortium, and private. Additionally, the more nodes in the ledger system 3, the larger the coefficient.

[0062] (2-2) User terminal 4

[0063] Figure 6 This is a block diagram illustrating the configuration of the user terminal 4 according to the embodiment. The user terminal 4 includes a camera unit 41, an identifier acquisition unit 42, a stored information acquisition unit 43, a hash value calculation unit 43, a consistency verification unit 44, an output unit 45, and an operation receiving unit 46. These various functional units are implemented by a processing unit such as a CPU included in the user terminal 4.

[0064] The camera unit 41 is a so-called camera device that includes a camera. For example, the camera unit 41 captures an arbitrary electronic signature S assigned to electronic content D. For example, the camera unit 41 captures an arbitrary electronic signature S included in electronic content D displayed on a display unit (not shown) of another terminal.

[0065] The identifier acquisition unit 42 acquires, at least the electronic certificate identifier contained in the captured electronic signature S (QR code) by photographing the electronic signature S.

[0066] The hash value calculation unit 43 calculates various hash values ​​based on the electronic content D. For example, the hash value calculation unit 43 can calculate the hash value of electronic content D containing the latest electronic signature S (post-signature hash value). Additionally, the hash value calculation unit 43 can also calculate the hash value of electronic content D that does not contain the latest electronic signature S (pre-signature hash value). Furthermore, the hash value calculation unit 43 can also calculate the hash value of electronic content D as original text that does not contain any electronic signature S (original text hash value).

[0067] The consistency verification unit 44 obtains the electronic certificate stored in the ledger system 3 via the management device 1, and performs a consistency verification process for the electronic content D related to the electronic content D. Through the consistency verification process of the electronic content D, it is possible to determine whether the electronic content D is authentic. For example, based on the electronic certificate identifier obtained by photographing any electronic signature S contained in the electronic content D, the consistency verification unit 44 verifies the consistency between the hash value (original hash value, hash value before signature, and / or hash value after signature) contained in the obtained electronic certificate obtained from the management device 1 and the hash value (original hash value, hash value before signature, and / or hash value after signature) calculated from the electronic content D by the hash value calculation unit 43. For example, the consistency verification unit 44 can also determine whether the original electronic content D has not been changed by determining whether the original hash value obtained from the object electronic content D is consistent with the original hash value contained in the electronic certificate. Furthermore, for example, the consistency verification unit 44 can also determine whether the electronic content D has remained unchanged between the time of the previous electronic signature S and the time of the latest electronic signature S by determining whether the pre-signature hash value obtained from the electronic content D (a hash value calculated based only on electronic content other than the latest electronic signature) is consistent with the post-signature hash value contained in the previous electronic certificate. A specific operation is as follows: For example, a user can access the original electronic content D stored in the management device 1 (electronic content database 2, etc.) by photographing the electronic signature S of the electronic content D printed on paper (hand-delivered, delivered, etc.) using the user terminal 4, and then display the electronic content D on the user terminal 4. The management device 1 can also calculate the hash value of the received accessed electronic content D and determine whether the electronic content D is authentic by querying the ledger system 3 for the hash value (original hash value, pre-signature hash value, and post-signature hash value). For electronic content D that is handed over or delivered by hand, for example, the user can verify the authenticity of electronic content D by visually comparing it with the electronic content D stored in the management device 1 displayed on the user terminal 4. Alternatively, for example, the authenticity of electronic content D stored in the management device 1 can be determined by querying the ledger system 3.

[0068] Output unit 45 outputs various information related to electronic content D. For example, output unit 45 outputs information about various electronic certificates obtained from management device 1. In addition, for example, output unit 45 outputs the confirmation result of consistency based on consistency confirmation unit 44.

[0069] The operation receiving unit 46 accepts various operations from the user. For example, the operation receiving unit 46 accepts the option to perform a confirmation process related to the electronic content D. Furthermore, the operation receiving unit 46 accepts, for example, the selection of various screen transitions or links displaying information related to the electronic content D.

[0070] The transceiver unit 47 receives and sends various information between the management device 1 and other user terminals 4. For example, the transceiver unit 47 sends an instruction for the signature of electronic content to the management device 1. In addition, the transceiver unit 47 receives, for example, electronic content D (containing an electronic signature S) or an electronic certificate from the management device 1.

[0071] (3) Work example

[0072] (3-1) Generation of electronic signatures and electronic certificates, etc.

[0073] Figure 7 This is a timing diagram illustrating an example of the electronic signature and electronic certificate generation processes performed by the electronic signature management system 100 according to the implementation method. The following explanation uses the case of an ordering company (as a user) and an order-receiving company (as another user) placing an order for goods / services. The user terminal 4 used by the ordering company is designated as user terminal 4A, and the user terminal 4 used by the order-receiving company is designated as user terminal 4B. In this case, the person in charge of the order-receiving company generates an electronic document D0 as a payment request for the goods / services. Furthermore, the electronic document D0 can be generated either by user terminal 4A using the electronic document generation service provided by the management device 1, or by using general document generation software that does not use such a service. Moreover, the generated electronic document D0 can be stored in the electronic document database 2 by the management device 1, or stored by user terminal 4A in a storage element accessible to user terminal 4A. Furthermore, this timing diagram uses the case of the electronic signature management system 100 in the embodiment processing electronic documents as electronic content as an example, but it is not limited to electronic documents and can also be applied to other electronic content such as electronic images.

[0074] When the user terminal 4A used by the person in charge of the order-receiving company receives an operation based on the signature instruction for electronic document D0 from the person in charge of the order-receiving company, it sends the signature instruction for electronic document D0 to management device 1 (S101). Management device 1 receives the signature instruction for electronic document D0 from user terminal 4A (S102).

[0075] The signature instruction for electronic document D0 may include, for example, the data of electronic document D0 itself, or information (such as a series ID) used to identify the electronic document D0 stored in electronic document database 2 or a storage element accessible by user terminal 4A. Furthermore, the signature instruction may also include, for example, any item stored in ledger system 3 (items related to the person in charge of the order-receiving company, etc.). Additionally, the signature instruction may also include, for example, the signature entered by the person in charge of the order-receiving company. In such cases... Figure 4 The example shown displays the signature of the "payment request" entered by the person in charge of the receiving company.

[0076] Management device 1 generates an electronic signature S1 based on the signature instruction, either from the person in charge of the order-receiving company or from an electronic certificate (S103). Regarding the generation of the electronic certificate, management device 1 generates the hash value of the electronic document D0 before the electronic signature S1 was assigned, and includes it as the pre-signature hash value in the electronic certificate. Additionally, management device 1 generates the hash value of the electronic document D1 after the electronic signature S1 was assigned, and includes it as the post-signature hash value in the electronic certificate. Furthermore, management device 1 generates the hash value of the electronic document D0 that does not contain any electronic signature S, and includes it as the original hash value in the electronic certificate. Management device 1 then stores the generated electronic certificate (e.g., as...) Figure 4 At least a portion of the electronic certificate shown in the first row is stored in the first ledger system 3A, the second ledger system 3B and the third ledger system 3C (S104).

[0077] Management device 1 generates electronic document D1 by assigning the generated electronic signature S1 to electronic document D0. Then, management device 1 sends the generated electronic document D1 to user terminal 4A (S105). User terminal 4A may also store the received electronic document D1 in a storage element accessible to user terminal 4A.

[0078] User terminal 4A sends electronic document D1 to user terminal 4B used by the person in charge of the ordering company, based on the operation of the person in charge of the ordering company (S106). Alternatively, the sending of electronic document D1 to user terminal 4B can also be performed via management device 1. User terminal 4B receives electronic document D1 (S107). User terminal 4B can also store the received electronic document D1 in a storage element accessible to user terminal 4B.

[0079] After the person in charge of the ordering company properly confirms the contents of the received electronic document D1 (the contents of the payment request), they perform an operation to instruct the signature of the electronic document D1 based on the person in charge of the ordering company. When the user terminal 4B accepts this operation, it sends the signature instruction for the electronic document D1 to the management device 1 (S108). The management device 1 receives the signature instruction for the electronic document D1 from the user terminal 4B (S109).

[0080] The signature instruction for electronic document D1 may include, for example, the data of electronic document D1 itself, or it may include information (such as a series ID) used to identify electronic document D1 stored in electronic document database 2 or a storage element accessible by user terminal 4B. Furthermore, the signature instruction may also include, for example, any item stored in ledger system 3 (items related to the person in charge of the ordering company, etc.). Additionally, the signature instruction may also include, for example, the signature content entered by the person in charge of the ordering company. In such cases... Figure 4 The example shown displays the signature "Pay as bill" entered by the person in charge of the ordering company.

[0081] Management device 1 generates an electronic signature S2 based on the signature instruction, either by the person in charge of the ordering company, or by generating an electronic certificate (S110). Regarding the generation of the electronic certificate, management device 1 generates the hash value of the electronic document D1 before the electronic signature S2 was assigned, and includes it as the pre-signature hash value in the electronic certificate. Additionally, management device 1 generates the hash value of the electronic document D2 after the electronic signature S2 was assigned, and includes it as the post-signature hash value in the electronic certificate. Furthermore, management device 1 generates the hash value of the electronic document D0 that does not contain any electronic signature S, and includes it as the original hash value in the electronic certificate. Management device 1 then stores the generated electronic certificate (e.g., as...) Figure 4 At least a portion of the electronic certificate shown in the second row is stored in the first ledger system 3A, the second ledger system 3B and the third ledger system 3C (S111).

[0082] Management device 1 can also determine whether the content of electronic document D1 has been changed. That is, management device 1 can also determine that the content of electronic document D1, which is the object to which electronic signature S2 is assigned, has not been changed from the content of the previous electronic document D1 to which electronic signature S1 was just assigned. For example, when management device 1 queries the ledger system 3, such as... Figure 4The hash value after the signature on the first line of the electronic certificate shown is compared with the hash value before the signature on the second line of the electronic certificate. If they match, it is determined that the electronic document D1 has not been altered; if they do not match, it is determined that the electronic document D1 has been altered. The management device 1 can also output the determination result to the user terminal 4B, etc. Thus, when the person in charge of the ordering company performs electronic signature S2, they can confirm the continuity of the content of the target electronic document D1.

[0083] Management device 1 generates electronic document D2 by assigning the generated electronic signature S2 to electronic document D1. Then, management device 1 sends the generated electronic document D2 to user terminal 4B (S112). User terminal 4B may also store the received electronic document D2 in a storage element accessible to user terminal 4B.

[0084] User terminal 4B, in response to the action of the person in charge of the ordering company, sends electronic document D2 to user terminal 4A used by the person in charge of the receiving company (S113). Alternatively, the sending of electronic document D2 to user terminal 4A can also be performed via management device 1. User terminal 4A receives electronic document D2 (S114). Furthermore, a notification of payment commitment can be sent from user terminal 4B to user terminal 4A, with or without going through management device 1. User terminal 4A can also store the received electronic document D2 in a storage element accessible to user terminal 4A.

[0085] (3-2) Inquiry of electronic certificate information

[0086] Figure 8 This is a flowchart illustrating an example of the electronic certificate information query processing performed by the management device 1 in the embodiment. The electronic certificate information query processing involves querying desired electronic certificate information from the multiple ledger systems 3 included in the electronic signature management system 100. The electronic certificate information query processing can be performed at any time, for example, when a query request for electronic certificate information is received from a user terminal 4, or when a new electronic signature for an electronic document is generated (e.g., the timeline of step S110 described above).

[0087] The response acquisition unit 18 may, for example, send a request to each ledger system 3 requesting electronic certificate information stored in each ledger system 3, and retrieve the electronic certificate information output by each ledger system 3 as a response to the request (S201). The response acquisition unit 18 may also perform this processing in response to a query request for electronic certificate information from the user terminal 4.

[0088] The total value calculation unit 19 calculates the total value of each identical answer contained in the multiple answers obtained by the answer acquisition unit 18 from the multiple ledger systems 3 by summing the coefficients associated with the ledger system 3 that output the answer (S202).

[0089] For example, the determination unit 20 determines one of the multiple answers obtained from each ledger system 3 as the answer that is consistent with the electronic certificate information based on the total value calculated by the total value calculation unit 19 (S203).

[0090] Here, taking an electronic signature management system 100 with three ledger systems 3 (first ledger system 3A, second ledger system 3B, and third ledger system 3C) as an example, a specific example of a method for determining an answer as consistent with the information in an electronic certificate by calculating a total value is illustrated.

[0091] Table 1

[0092]

[0093] For example, as shown in Table 1, for a specified request for electronic certificate information, assume the response from the first ledger system 3A is "123", the response from the second ledger system 3B is "123", and the response from the third ledger system 3C is "456". Assume the coefficients of the first ledger system 3A, the second ledger system 3B, and the third ledger system 3C are all "1".

[0094] In this case, the total value calculation unit 19 calculates the total value of the answer "123" as the sum of the coefficients of the ledger system 3 that output the answer, that is, "2" which is the sum of the coefficient "1" of the first ledger system 3A and the coefficient "1" of the second ledger system 3B. In addition, in this case, the total value calculation unit 19 calculates the total value of the answer "456" as the sum of the coefficients of the ledger system 3 that output the answer, that is, "1" which is the sum of the coefficients "1" of the third ledger system 3C. Then, the determination unit 20 determines that the total value "2" of the answer "123" is the highest among all the total values ​​of the answers (answer "123" and answer "456"), and therefore determines that the answer "123" is consistent with the electronic certificate information.

[0095] Furthermore, as described above, when the coefficients of all ledger systems 3 are equal, such as when the coefficients of the first ledger system 3A, the second ledger system 3B, and the third ledger system 3C are all "1", essentially a majority vote by multiple ledger systems 3 determines an answer that is consistent with the electronic certificate information. Additionally, when the number of ledger systems 3 in the electronic signature management system 100 according to the embodiment is odd, in principle, the number of answers with the highest total value is limited to one, thus effectively determining the answer that is consistent with the electronic certificate information.

[0096] Table 2

[0097]

[0098] Additionally, as shown in Table 2, for a specified request for electronic certificate information, assume the response from the first ledger system 3A is "123", the response from the second ledger system 3B is "123", and the response from the third ledger system 3C is "456". Assume the coefficient for the first ledger system 3A is "1", the coefficient for the second ledger system 3B is "1.5", and the coefficient for the third ledger system 3C is "3".

[0099] In this case, the total value calculation unit 19 calculates the total value of the answer "123" as "2.5" of the sum of the coefficients of the ledger system 3 that output the answer, namely the sum of the coefficient "1" of the first ledger system 3A and the coefficient "1.5" of the second ledger system 3B. In the same case, the total value calculation unit 19 calculates the total value of the answer "456" as "3" of the sum of the coefficients of the ledger system 3 that output the answer, namely the sum of the coefficients "3" of the third ledger system 3C. Then, the determination unit 20 determines that the total value "3" of the answer "456" is the highest among all the total values ​​of the answers (answer "123" and answer "456"), and therefore determines that the answer "456" is consistent with the electronic certificate information.

[0100] The transceiver unit 21 sends the response that the determination unit 20 has determined to be consistent with the electronic certificate information to the user terminal 4 (S204).

[0101] (4) Notes

[0102] In the above embodiments, the determination process for whether the electronic content (electronic document) has been altered is performed in the sequence of generating an electronic signature in response to the signature instruction (steps S110, S206, S214, S307). However, the determination process for whether the alteration has occurred is not limited to these sequences. For example, it can also be performed at any time when the user requests the determination from the management device 1 via the user terminal 4. In this case, the user terminal 4 can also be, for example, receiving information about the electronic signature specified as the object of the determination process and including this information in the determination request, and sending it to the management device 1. The management device 1 compares the hash value before the signature of the specified electronic signature with the hash value after the signature of the previous electronic signature. If they match, it is determined that the electronic document (electronic content) has not been altered when the specified electronic signature was given; if they do not match, it can also be determined that the electronic document (electronic content) has been altered when the specified electronic signature was given.

[0103] The aforementioned electronic signature management system 100 can also be applied to situations where any user modifies the contract content after it has been signed. Specifically, firstly, for example, if a user needs to modify the content of a signed contract (delivery date or amount, etc.), they retrieve the electronic document on their user terminal 4. The user terminal 4 then retrieves the electronic document from the electronic document database 2 via the management device 1. Next, the user terminal 4 appropriately modifies the electronic document in response to the user's operation. Then, in response to the user's operation, the user terminal 4 sends a signature instruction for the modified electronic document (modified electronic document) to the management device 1. The management device 1 generates an electronic signature for the modified electronic document and assigns it to the modified electronic document.

[0104] The modified electronic document with an electronic signature can be sent from the management device 1 to the user terminal 4 used by other users (such as the counterparty to the contract). Then, after confirming the content of the modified electronic document displayed on the user terminal 4, the other user performs an electronic signature operation on the modified electronic document relative to the user terminal 4. The user terminal 4 sends a signature instruction to the management device 1, which generates the other user's electronic signature and further assigns it to the modified electronic document (the electronic document with the aforementioned user's electronic signature). Thus, for example, it is possible to modify the contract content on the same electronic document without exchanging modification memos. In conventional electronic signatures, there are cases where the original electronic signature becomes invalid by changing the content of the electronic document or its hash value. On the other hand, in the electronic signature management system 100 according to the embodiment, since even if the hash value of the electronic document changes due to the electronic signature, a series of related electronic signatures can be identified through a series ID (system identification information), thus making the management of contract content modifications simple.

[0105] The aforementioned electronic signature management system 100, because it can identify a series of related electronic signatures through a series ID (system identification information) even if the hash value of electronic content changes due to electronic signatures, is not limited to contracts. If we assume that electronic signatures are assigned sequentially, it can be applied to any electronic content. For example, the electronic signature management system 100 can also be applied in situations such as signature campaigns in political activities where multiple signatories sequentially sign electronic documents in a signature register.

Claims

1. A management device for managing electronic signatures on electronic content, comprising: The Acquisition Department obtains instructions regarding the attribution of electronic content; The signature generation unit generates an electronic signature in response to the instruction; The assigning department assigns the generated electronic signature to the electronic content; The electronic certificate generation department generates electronic certificates associated with the electronic signature; The electronic certificate information storage unit performs processing for storing electronic certificate information, which is at least a part of the electronic certificate, in each of the multiple ledger systems. The response acquisition unit acquires multiple responses to the request as outputs from each of the multiple ledger systems by sending a request to each of the multiple ledger systems for the electronic certificate information stored in each ledger system. The total value calculation unit calculates the total value of each identical answer contained in the plurality of answers by summing the coefficients associated with the ledger system that output the answer. The determining unit, based on the total value, determines one of the multiple answers as the answer consistent with the information in the electronic certificate; and The output section outputs the given answer.

2. The management device according to claim 1, wherein, The determining unit identifies the answer with the highest total value as the answer.

3. The management device according to claim 1, wherein, At least one of the multiple ledger systems is a distributed ledger system.

4. The management device according to claim 1, wherein, The coefficients are determined based on characteristic information representing the characteristics of the ledger system.

5. The management device according to claim 4, wherein, The characteristic information is determined based on at least one of the algorithm used by the ledger system to store data and the number of nodes contained in the ledger system.

6. The management device according to claim 1, wherein, The coefficients associated with each of the plurality of ledger systems are equal.

7. The management device according to claim 6, wherein, The number of the multiple ledger systems is odd.

8. The management device according to claim 1, wherein, The electronic content refers to electronic documents.

9. The management device according to claim 1, wherein, The electronic certificate information is a hash value generated based on the electronic content.

10. A control method, executed by a management device for managing electronic signatures on electronic content, comprising: Steps to obtain instructions on authorizing electronic content; The step of generating an electronic signature in response to the instruction; The step of assigning the generated electronic signature to the electronic content; The steps for generating an electronic certificate associated with the electronic signature; The steps of performing processing to store electronic certificate information, which is at least a part of the electronic certificate, in each of the multiple ledger systems; The steps involve sending a request to each of the plurality of ledger systems for the electronic certificate information stored in each ledger system, and obtaining multiple responses to the request as outputs from each of the plurality of ledger systems. The step of calculating the sum of each identical answer contained in the plurality of answers by summing the coefficients associated with the ledger system that output the answer; Based on the total value, the step of determining one of the multiple answers as the answer consistent with the information in the electronic certificate; and The steps to output the above answer.

11. A program for enabling an information processing device to function as a management device for managing electronic signatures on electronic content. The management device functions as the following components: The Acquisition Department obtains instructions regarding the attribution of electronic content; The signature generation unit generates an electronic signature in response to the instruction; The assigning department assigns the generated electronic signature to the electronic content; The electronic certificate generation department generates electronic certificates associated with the electronic signature; The electronic certificate information storage unit performs processing for storing electronic certificate information, which is at least a part of the electronic certificate, in each of the multiple ledger systems. The response acquisition unit acquires multiple responses to the request as outputs from each of the multiple ledger systems by sending a request to each of the multiple ledger systems for the electronic certificate information stored in each ledger system. The total value calculation unit calculates the total value of each identical answer contained in the plurality of answers by summing the coefficients associated with the ledger system that output the answer. The determining unit, based on the total value, determines one of the multiple answers as the answer consistent with the information in the electronic certificate; and The output section outputs the given answer.

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