JP4390222B1 - Electronic data management method - Google Patents

Abstract

In an electronic data management method using a time stamp service, there is provided an electronic data management method capable of reducing the use cost of a time stamp service by a third-party organization and identifying falsified electronic data. .
In an electronic data management method for sequentially storing a plurality of electronic data in a storage device of a management server while utilizing a time stamp service provided by a third party, a fingerprint of the electronic data stored immediately before is stored. The electronic data storing step of sequentially storing the electronic data to which the fingerprint is added to the storage device while giving the electronic data to the electronic data, and the time by a third party for the electronic data to which the predetermined fingerprint is given A time stamp acquisition step of acquiring a stamp and storing the time stamp in the storage device.
[Selection] Figure 1

Description

  The present invention relates to an electronic data management method for managing electronic data, and more particularly, to an electronic data management method using a time stamp service.

  2. Description of the Related Art Conventionally, electronic data management systems for storing and managing electronic data such as electronic file data created by a PC and image data obtained by reading a document with a scanner have been provided.

  In addition, in order to prove that electronic data has existed at a certain time (proof of existence) and that it has not been altered or altered after that time (originality guarantee) A time stamp service (time authentication service) is widely provided, and there are many systems using the time stamp service even in conventional electronic data management systems.

However, in the time stamp service, a third party TSA (Time-Stamping: Time-Stamping
Charges are made according to the number of times of accessing the authority's server and performing time stamping. Therefore, if the number of electronic data is enormous, the charge will increase accordingly and the cost will increase.

  In order to solve such a problem, for example, in Patent Document 1 below, time stamping is performed on integrated data obtained by collecting a plurality of electronic data in a folder, thereby reducing the number of times the time stamp service is used. A folder-type time authentication system that reduces costs is provided.

JP 2001-142398 A

  However, in the folder-type time authentication system disclosed in Patent Document 1, time stamps are acquired collectively for a plurality of electronic data included in the same folder. Even if it is found that the falsification has occurred, the electronic data in the folder cannot be identified.

  The present invention has been made to solve such a problem, and in the electronic data management method using the time stamp service, the use cost of the time stamp service by a third party organization has been reduced and tampered. An object of the present invention is to provide an electronic data management method capable of specifying electronic data.

In order to solve the above problems, an electronic data management method according to the present invention is an electronic data management method for sequentially storing a plurality of electronic data in a storage device of a management server using a time stamp service. Electronic data in which the arithmetic device assigns the fingerprint of the electronic data stored immediately before to the next electronic data and groups the electronic data to which the fingerprint is added in the storage device in a group with a predetermined cycle. A storage step, and a time at which the arithmetic device acquires a time stamp by a third party for the electronic data to which the predetermined fingerprint in each group is assigned, and stores the time stamp in the storage device comprising a stamp obtaining step, wherein the electronic data storage step, the time stamp obtaining Engineering Characterized in that the electronic data time stamp is acquired, a step of further applying the fingerprint of a plurality of electronic data retrieved at predetermined intervals from the electronic data of the previous group by.

The management server according to the present invention includes a computing device that performs various computations and a storage that stores a plurality of electronic data in a management server that constitutes an electronic data management system connected to a time stamp station server via a network. And the arithmetic unit adds the fingerprint of the electronic data stored immediately before to the next electronic data and groups the electronic data with the fingerprint sequentially while grouping them with a predetermined cycle. Electronic data storage control to be stored in the storage device, and obtaining a time stamp from the time stamp authority server for the electronic data to which the predetermined fingerprint in each group is assigned, and storing the time stamp in the storage device a time stamp obtaining control to store, there is performing, the electronic data storage The control further adds fingerprints of a plurality of electronic data taken out at a predetermined interval from the electronic data of the previous group to the electronic data whose time stamp is acquired by the time stamp acquisition control. It is characterized by being.

An electronic data management program according to the present invention is stored immediately before an electronic data management program that allows a computer to perform electronic data management in which a plurality of electronic data is sequentially stored in a storage device using a time stamp service. Electronic data storing step of sequentially storing the electronic data to which the fingerprint is given to the storage device while giving the fingerprint of the electronic data to the next electronic data and grouping them at a predetermined cycle, timestamp is obtained by a third party with respect to electronic data given the fingerprint has been applied, be one to be executed and a time stamp obtaining step of storing the time stamp in the storage device, to the computer The electronic data storage step includes the time stamp. The electronic data time stamp is acquired by the acquisition step, and characterized in that the step of further applying the fingerprint of a plurality of electronic data retrieved at predetermined intervals from the electronic data of the previous group To do.

  According to the electronic data management method of the present invention, it is possible to reduce the cost of using a time stamp service by a third party organization and to specify falsified electronic data.

  Hereinafter, an electronic data management method according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram schematically showing a configuration of an electronic data management system according to the present embodiment. FIG. 2 is a schematic diagram schematically showing the configuration of the management server according to the present embodiment. In the present embodiment, an electronic data management method used in a medical institution will be described as an example in which a medical record is stored as electronic data.

  As shown in FIG. 1, an electronic data management system 1 according to this embodiment includes a management server 10 that is a server for managing the system, and client terminals 20A to 20D for inputting medical records as electronic document data. Yes. The management server 10 and the client terminal 20 are connected by a LAN 40 and can perform data communication with each other. The LAN 40 is connected to a public line network 50 such as the Internet. The management server 10 uses the TSA server 30 via the public line network 50 in order to use a time stamp service operated by a third party. Is accessible.

  Each client terminal 20 includes a scanner 22, and each terminal 20 can take a medical chart as image electronic data into a storage device in the personal computer body. Each client terminal 20 is configured to sequentially transmit the captured electronic data of the medical chart to the management server 10.

  Each client terminal 20 adds “scan date / time”, “scanner number”, “series number”, “page number”, “scanner name”, “administrator name” to the scanned medical chart image data. ”Or the like is generated as a binary code, and the electronic data is generated and transmitted to the management server 10.

As shown in FIG. 2, the management server 10 has a CPU (Central
An arithmetic device 11 such as a processing unit, a timer 12 that functions as a clock, and a storage device 13 such as an HDD (Hard Disc Drive) that stores various types of information are provided. The storage device 13 stores a program DB 131 that stores various programs for executing predetermined processing in the management server 10, and an electronic data DB 132 that stores electronic data obtained by performing predetermined processing on electronic data acquired from each client terminal 20. And a time stamp DB 133 for storing the time stamp acquired from the TSA server 30.

  In the management server 10, the processing number is given to the electronic data received from each client terminal 20 by the processing of the computing device 11, and the electronic data to be sequentially stored is provided with continuity (connection) as will be described later. The electronic data is recorded in the electronic data DB 132 of the storage device 13.

  Next, the basic concept of processing when storing electronic data in the present embodiment will be described with reference to FIG. FIG. 3 is a flowchart showing a basic concept of processing when storing electronic data according to the present embodiment. In the present embodiment, in order to provide connection (continuity) to the electronic data sequentially stored in the management server 10, a fingerprint (characteristic) that is uniquely determined from the electronic data stored immediately before is stored. Information) is embedded. Specifically, the hash value obtained by applying the hash function to the previous electronic data is embedded in the next electronic data as a fingerprint.

As shown in the figure, first, in S10, the chart is scanned by the scanner 22 of the client terminal 20, and chart image data is generated. Subsequently, in S _< b _> 11, the status information described above is added to the image data, and the electronic data _An is created by the client terminal 20.

In S <b _> 12, the created electronic data _An is transmitted from the client terminal 20 to the management server 10 via the LAN 40. Then, the management server 10, in S13, the electronic data A _n received, the process number is assigned in the order received.

In S14, the hash value h (B _n-1 ) of the electronic data B _n-1 stored in the management server 10 immediately before is obtained by the computing device 11 (the hash function is assumed to be h). As described above, the hash value h (B _n-1 ) of the previous electronic data is further added to the electronic data to which the processing number is assigned in S13, and the hash value-added electronic data B _n is created. In S15, the hash value-added electronic data _Bn created in S14 is stored in the electronic data DB 132. Of course, the original image data, status information, processing number, hash value h (B _n-1 ) and the like can be extracted independently from the created electronic data Bn.

  The above-described S10 to S15 are basic processes for storing electronic data in the present embodiment, but in the present embodiment, electronic data that is stored at predetermined intervals while sequentially storing electronic data relating to medical charts. The time stamp is acquired. In this embodiment, using this time stamp and the continuity of the stored electronic data, it is possible to perform falsification verification of the electronic data while going back sequentially starting from the electronic data to which the time stamp is given. It has become.

For the electronic data for which the time stamp is acquired, the processing of S20 to S23 shown in FIG. 3 is further performed. First, in S20, the management server 10 accesses the TSA server 30 of the time stamp authority, which is a third-party certification organization, via the public network 50, requests generation of a time stamp, and is calculated by the management server 10. The hash value h (B _n ) of the electronic data B _n is transmitted to the TSA server 30.

  In S21, the TSA server 30 integrates the received hash value and the current time information to create a time stamp token. Subsequently, in S <b> 22, the TSA server 30 replies to the management server 10 after electronically signing the created time stamp token with a secret key. In S23, the management server 10 stores the received time stamp token in the time stamp DB 133.

  When verifying the time stamp, the management server 10 first calculates the hash value of the electronic data to be verified from which the time stamp has been acquired. Then, a hash value is extracted from the time stamp token acquired for the electronic data using the public key of the TSA server, and compared with the calculated hash value.

  If these hash values match, it can be proved that the electronic data existed at the time when the time stamp was created, and the electronic data has not been falsified (changed) from that time to the present. Can also prove. Note that the processing in the management server 10 described above is realized by the arithmetic device 11 executing a predetermined program stored in the program DB 131.

  Next, a processing method for storing electronic data in the medical chart scan according to the present embodiment will be described in detail with reference to FIG. FIG. 4 is a schematic diagram for explaining the electronic data storage processing method according to the present embodiment.

  The electronic data management system 1 according to the present embodiment is a system for managing medical charts of medical institutions. As shown in FIG. 4, the electronic data is grouped for each day, and the first and last electronic data of the day are grouped. It is configured to give a time stamp by a tripartite organization.

First, on the first day (first day) when the system 1 is introduced, the management server 10 creates electronic data X ₁₀ of a start file in which predetermined status information and processing No. 0 are embedded, and for this electronic data, To get a timestamp.

After creating electronic data X _10, management server 10 starts the reception of the scanned electronic data. Note that the subscript a of the electronic data X _ab indicates the number of days from the start of operation, and the subscript b indicates the processing number. The electronic data X ₁₁ received first from the client terminal 20 is given as a fingerprint A the hash value of the electronic data with the previous processing number of the same day, in order to have continuity. That is, the electronic data X ′ _{11 in} which the hash value h (X ₁₀ ) of the electronic data X ₁₀ of the start file is embedded is stored in the electronic data DB 132 of the storage device 13.

Subsequently, the hash value h (X ₁₁ ) (fingerprint A) of the electronic data X ′ ₁₁ is embedded in the electronic data X ₁₂ received second on the first day, and the electronic data X ′ ₁₂ is stored. In this way, the electronic data X _{1n is} sequentially embedded with the hash value h (X ′ _1n−1 ) of the immediately preceding electronic data and the fingerprint of the previous electronic data X ′ _1n−1 is embedded. X ′ _1n is stored in the electronic data DB 132.

At the end of the first day, end electronic data E ′ obtained by adding the hash value h (X ′ _1n ) of the electronic data stored immediately before the management server 10 to the end data E ₁ such as the administrator name and the number of scans of the day. ₁ is stored in the electronic data DB 132 and the time stamp of the end electronic data E ′ ₁ is acquired from the TSA server 30 and stored in the time stamp DB 133.

  On the second day, before starting the medical chart scanning process, a method to be described later is used to verify whether all electronic data stored on the previous day has been falsified. The chart scan process is started, and if at least one falsified electronic data exists, an alert is generated and the same process as the first day is performed as the first day chart scan.

In the process on the second day, first, three hash values (fingerprints A, B, and C) are embedded in the electronic data X ₂₁ for the first medical chart scan to generate electronic data X ′ _21. . The fingerprint A is a hash value of electronic data corresponding to the previous scan data, and here is a hash value h (X ′ _1n ) of the last electronic data X ′ _1n of the previous day (the first day). .

The fingerprint B is a hash value of electronic data taken out from the previous day's electronic data at a predetermined interval, and here, is a hash value h (X ′ _1a ) of the electronic data X ′ _1a . Although one hash value is shown as the fingerprint B in FIG. 4, a plurality of hash values are usually given as the fingerprint B. The fingerprint C is a fingerprint A included in the electronic data of the same processing number on the previous day, and here, a hash value which is the fingerprint A included in the electronic data X ′ ₁₁ of the same processing No. 1 on the first day h (X ′ ₁₀ ).

  Here, the predetermined interval when extracted as the hash value of the fingerprint B may be, for example, every predetermined number of electronic data such as 100. Moreover, it may be every predetermined time, such as every hour, and it is not limited to a certain period, and the administrator may manually specify it at random. In this way, if the hash value of the electronic data of the previous day is also inserted as a benchmark at a predetermined interval, it will benefit from shortening the verification time and greatly improving the possibility of falsification verification as will be described later. it can.

Then, an electronic data stored in the first 2 days electronic data X 'with respect to ₂₁ to obtain the time stamp, electronic data X' stored in the storage device 13 together with _21. Subsequently, for the next received electronic data X ₂₂ , the hash value h (X ′ ₂₁ ) (fingerprint A) of the previous electronic data by the processing of the arithmetic device 11 and the same processing No. 2 of the previous day Electronic data X ′ ₂₂ to which a hash value h (X ′ ₁₁ ) that is a fingerprint A of data is assigned is created, and the electronic data X ′ ₂₂ is stored in the electronic data DB 132.

  In this way, by adding the hash value (fingerprint A) embedded in the electronic data of the same processing number of the previous day to the electronic data to be stored, the verification time can be shortened or altered as described later. Benefit from greatly improving the possibility of verification.

Subsequently, for the electronic data X ₂₃ , X ₂₄ ,..., X _2n−1 , X _2n acquired sequentially on the second day, the hash value of the immediately preceding electronic data and the electronic data of the same processing number on the first day are changed. Electronic data X ′ ₂₃ , X ′ ₂₄ ,..., X ′ _2n−1 , X ′ _2n to which the hash value of the embedded fingerprint A is _assigned are sequentially stored in the electronic data DB 132.

At the end of the second day, end data E ₂ is created as in the first day, and a hash value h (X) of X ′ _2n corresponding to the last chart scan data of the second day is added to the end data E _2. The hash value-added electronic data E ′ ₂ assigned with “ _2n ) is stored in the electronic data DB 132, and the management server 10 acquires a time stamp for the electronic data E ′ ₂ from the TSA server 30 and stores it in the time stamp DB 133. save.

Subsequently, on the third day, h (X ′ _2n ) as a fingerprint A, which is a hash value of the previous electronic data, is stored on the previous day with respect to the electronic data X ₃₁ corresponding to the first chart scan data. H (X ′ _2a ) as a fingerprint B, which is a hash value of electronic data extracted from the electronic data at a predetermined interval, and a fingerprint C, which is a hash value included in the same electronic data with the processing number of the previous day The electronic data X ′ _{31 assigned} with h (X ′ _1n ) is generated and stored in the storage device 13, and the time stamp of the electronic data X ′ ₃₁ is acquired and stored in the storage device 13. Thereafter, the electronic data acquired by the management server 10 is sequentially stored in the storage device 13 as in the second day.

  As described above, the method for storing the electronic data subjected to the chart scan in the electronic data management method according to the present embodiment has been described in detail. Subsequently, the falsification verification for verifying whether the electronic data stored in the present embodiment has been falsified. The method will be described. In this embodiment, there are mainly three types of verification methods, which will be sequentially described.

First, the first falsification verification method is a method of performing falsification verification of electronic data on the same day from end data using the hash value of the fingerprint A described above. For example, when the electronic data X _2n-1 in FIG. 4 is used as the verification target data, the management server 10 first uses the time stamp of the electronic data E ′ ₂ stored in the time stamp DB 133 to perform electronic data E ' ₂ falsification verification is performed. 'If proof non tampering of _2, electronic data E' electronic data E hash value h (X _'2n) contained in ₂ is also a non-tampering.

Subsequently, the hash value h (X ′ _2n ) proved to be non-falsified is compared with the hash value calculated from the electronic data X ′ _2n stored in the electronic data DB 132. Since the data X ′ _{2n is} also not tampered with, the hash value h (X ′ _2n−1 ) included in the electronic data X ′ _2n is not tampered.

Then, the hash value h (X ′ _2n−1 ) proved to be non-falsified is compared with the hash value calculated from the electronic data X ′ _2n−1 stored in the electronic data DB 132, and they match. long as it 'it is demonstrated _2n-1 is a non-tampering, the electronic data X' electronic data X to the electronic data X _2n-1 included in the _2n-1 is demonstrated to be non-tampered Become.

  In this way, if fingerprint A is used, electronic data that has been sequentially stored in a chained manner while being given fingerprint A of the previous electronic data, starting from electronic data that has been given a time stamp by a third party. It is possible to verify non-falsification while going back in the reverse direction.

  As described above, this first falsification verification method is used when it is desired to perform falsification verification on all electronic data stored on the previous day before the start of a day's scan. In the present embodiment, since the fingerprint of the last electronic data of the previous day is also embedded in the first electronic data of the next day, it is possible to perform falsification verification across days using the fingerprint A.

Next, in the second falsification verification method, the falsification verification of the predetermined electronic data extracted as the benchmark of the previous day is performed from the first electronic data of the predetermined day using the hash value of the fingerprint B described above. Is the method. For example, when the electronic data X _2a in FIG. 4 is used as verification target data, first, falsification verification of the electronic data X ′ ₃₁ is performed using the time stamp of the electronic data X ′ ₃₁ stored in the time stamp DB 133. Do.

If it can be proved from the time stamp that the electronic data X ′ ₃₁ has not been tampered with, the hash value h (X ′ _2a ) included in the electronic data X ′ ₃₁ is also non-tampered. Therefore, the hash value h (X ′ _2a ) proved to be non-falsified is compared with the hash value calculated from the electronic data X ′ _2a stored in the electronic data DB 132. 'since _2a is also at non-alteration, electronic data X' X can prove that electronic data X _2a contained in _2a is non-tampering.

  According to the second falsification verification method, the verification time can be shortened when the distance between the verification target data and the end electronic data is long and verification takes time in the first falsification verification method. . In the first falsification verification method, if there is falsified electronic data between the end electronic data to which the time stamp is given and the data to be verified, the electronic data ahead of the falsified electronic data is traced back. However, falsification verification can be performed even in such a case by combining the second falsification verification method using a hash value incorporated as a benchmark.

Next, in the third falsification verification method, falsification verification of the electronic data of the previous day is performed from the electronic data of the next day in which the hash value of the electronic data of the previous day is embedded using the hash value of the fingerprint C described above. Is the method. For example, when the electronic data X _2n-1 in FIG. 4 is to be verified, first, the electronic data X ′ _3n has been falsified using the first falsification verification method or the second falsification verification method. Prove that there is no.

'If proven that _3n not been falsified, the electronic data X' electronic data X hash value h (X _'2n-1) contained in the _3n is also non-tampering. Therefore, the hash value h (X ′ _2n−1 ) proved to be non-falsified is compared with the hash value calculated from the electronic data X ′ _2n−1 stored in the electronic data DB 132, and they match. if, 'since it is _2n-1 or non-tampering, the electronic data X' electronic data X can prove that the electronic data X _2n-1 included in the _2n-1 is a non-tampering.

  According to the third falsification verification method, even if the verification cannot be performed by the first and second falsification verification methods, the third falsification verification method can be used for verification.

  As described above, the embodiment of the present invention has been described in detail, but various processes in the management server 10 described above in the present embodiment are realized by the arithmetic device 11 executing a predetermined program stored in the program DB 131. . The distribution of the predetermined program may be performed via a recording medium or via a network.

  According to this embodiment, for a plurality of electronic data to be sequentially stored, electronic data that has not been acquired by only acquiring a time stamp by a third party for selected predetermined electronic data. Tampering verification can be performed, and the cost of using the time stamp service can be greatly reduced.

  Further, in the present embodiment, since the electronic data to be stored has continuity by sequentially adding the fingerprint of the previous electronic data, the electronic data to be subjected to falsification verification is described above. By appropriately using the first to third falsification verification methods using the fingerprints A to C alone or in combination, the speed and accuracy of the falsification verification can be significantly improved.

  As mentioned above, although embodiment of this invention was described in detail, embodiment of this invention is not limited to the said embodiment, A various deformation | transformation is possible within the range which does not deviate from the main point of this invention. . For example, in this embodiment, image data obtained by reading a medical chart in a medical institution with a scanner has been described as an example of electronic data to be managed. However, document data other than medical charts, image data such as photographs, and further, a personal computer Various electronic data can be managed as long as it is data that can be stored in a storage medium as electronic data, such as created word processing document data or spreadsheet software data.

  In this embodiment, the electronic data to be managed is configured to be transmitted from the client terminal connected to the management server via the network to the management server. Of course, a scanner is directly connected to the management server. The electronic data directly taken into the management server or the electronic data created directly in the management server may be managed.

  Further, in the present embodiment, the case where the arithmetic device, the timer, and the storage device of the management server are integrally configured has been described as an example. However, even if these are connected via a network and arranged separately. good.

  In the present embodiment, the electronic data to be stored every day is grouped. However, the time period for grouping can be changed as appropriate, such as every hour or every week. Alternatively, grouping may be performed according to the cycle of the number of electronic data to be stored, such as grouping every time 1,000 electronic data are stored. However, in the case of grouping, a time stamp is acquired for the electronic data stored at the end of the group so that retrospective verification within the group by the first falsification verification method is possible. It is desirable to keep it.

FIG. 1 is a schematic diagram schematically showing a configuration of an electronic data management system according to the present embodiment. FIG. 2 is a schematic diagram schematically showing the configuration of the management server according to the present embodiment. FIG. 3 is a flowchart showing a basic concept of processing when storing electronic data according to the present embodiment. FIG. 4 is a schematic diagram for explaining the electronic data storage processing method according to the present embodiment.

Explanation of symbols

1 Electronic Data Management System 10 Management Server 11 Arithmetic Device 12 Timer 13 Storage Device 131 Program DB
132 Electronic Data DB
133 Timestamp DB
20 Client terminal 21 Scanner 30 TSA server 40 LAN
50 Public line network

Claims (5)

In an electronic data management method for sequentially storing a plurality of electronic data in a storage device of a management server while using a time stamp service,
The computing device of the management server assigns the fingerprint of the electronic data stored immediately before to the next electronic data and groups them at a predetermined cycle, and sequentially stores the electronic data to which the fingerprint is attached to the storage device. Electronic data storage process to be stored ;
A time stamp acquisition step of acquiring a time stamp by a third party for the electronic data to which the predetermined fingerprint in each group is assigned, and storing the time stamp in the storage device; , equipped with a,
The electronic data storage step includes fingerprints of a plurality of electronic data taken out at a predetermined interval from the electronic data of the previous group with respect to the electronic data whose time stamp is acquired by the time stamp acquisition step. Furthermore , the electronic data management method characterized by being the process to provide. Said electronic data storage step, the electronic data stored, included in the electronic data of one same process number of the previous group, a step of further applying the fingerprint of the electronic data stored immediately before The electronic data management method according to claim 1, wherein: 3. The electronic data management method according to claim 1, wherein the time stamp acquisition step is a step of acquiring a time stamp for at least the last electronic data in each group. In a management server constituting an electronic data management system connected to a time stamp station server via a network,
An arithmetic device for performing various operations;
A storage device for storing a plurality of electronic data,
The computing device, electrons stored fingerprint of the electronic data stored immediately before while grouped in a predetermined period while applying the next electronic data, the sequential electronic data this fingerprint is applied to the memory device Data storage control,
From the TSA server for electronic data given the fingerprint has been applied in each group to obtain a time stamp, which the time stamp perform a time stamp obtaining control to store in the storage device Because
The electronic data storage control includes fingerprints of a plurality of electronic data taken at predetermined intervals from the electronic data of the previous group with respect to the electronic data whose time stamp is acquired by the time stamp acquisition control. Further , a management server characterized by control to be given . In an electronic data management program for causing a computer to perform electronic data management for sequentially storing a plurality of electronic data in a storage device while using a time stamp service,
An electronic data storage step of sequentially storing the electronic data to which the fingerprint has been attached to the storage device while giving the fingerprint of the electronic data stored immediately before to the next electronic data and grouping at a predetermined cycle ;
A time stamp acquisition step of acquiring a time stamp by a third party for electronic data to which the predetermined fingerprint in each group is assigned and storing the time stamp in the storage device is executed on a computer be one that makes,
The electronic data storing step includes fingerprints of a plurality of electronic data taken out at a predetermined interval from the electronic data of the previous group with respect to the electronic data whose time stamp is acquired by the time stamp acquiring step. Further , an electronic data management program characterized by being a step of giving .

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