JP4484377B2 - Data management method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a data management technique, and more particularly to a technique for managing data owned by a user using a network.
[0002]
[Prior art]
Conventionally, data such as an electronic photograph or video stream created or acquired by a user is stored on a large-capacity hard disk such as a personal computer owned by the user, a DVD, a CD-R, etc., unless it is intended to be widely disclosed. It was stored locally.
[0003]
[Problems to be solved by the invention]
However, for example, when a large amount of data is obtained by a portable terminal or the like, the memory of the portable terminal or the like is occupied by the data, and there is a problem that a memory area for storing other data is reduced. is there.
[0004]
Even when data created by a user is stored in a personal computer or the like, important data may be lost if the installation location is affected by a disaster such as a fire, an earthquake, or a typhoon.
[0005]
Accordingly, an object of the present invention is to provide a data management technique for suitably managing electronic data owned by a user.
[0006]
[Means for Solving the Problems]
According to the present invention, Head Server and With multiple data servers Network system including client terminal by A data management method, Generalization server Means of accepting , Said A reception step of accepting a data storage request by a user from a client terminal; Head server The selection method is , Among the plurality of data servers, Said A data storage request was made A selection process for selecting a data server installed in an area that has a certain relationship with the area set by the user; The transmission step of the central server transmits the address of the data server selected in the selection step to the client terminal, and Said Head server Storage means , In the selection process To the selected data server for , Send data related to the data storage request The A storing step for storing; The acquisition means of the client terminal accesses the selected data server based on the address transmitted in the transmission step, so that the data stored in the data server can be stored without going through the central server. An acquisition step of acquiring A data management method is provided.
[0008]
According to the present invention, the accepting means for accepting the data storage request by the user transmitted from the client terminal via the communication line; Installed in a different area from the address of the user who made the data storage request from multiple data servers A selection means for selecting a data server; The transmitting means for transmitting the address of the data server selected by the selecting means to the client terminal, and the selecting means To the selected data server for , Send data related to the data storage request via the communication line Store And a server comprising the means.
[0009]
Further, according to the present invention, the accepting means for accepting the data storage request by the user transmitted from the client terminal via the communication line, Installed in a different area from the address of the user who made the data storage request from multiple data servers Selection means for selecting a data server, The transmitting means for transmitting the address of the data server selected by the selecting means to the client terminal, the selecting means To the selected data server for , Send data related to the data storage request via the communication line Store A program that functions as means is provided.
[0010]
According to the present invention, there is provided a data management system including a central server, a client terminal, and a plurality of data servers that can communicate with each other via a communication line, wherein the central server is connected to the client terminal. A receiving means for accepting the transmitted data storage request by the user; plural From within the data server Installed in an area different from the address of the user who made the data storage request A selection means for selecting a data server; A first transmission means for transmitting the address of the data server selected by the selection means to the client terminal; and the selection means. To the selected data server for , Send data related to the data storage request Second transmission Means, and The client terminal obtains data stored in the data server without going through the central server by accessing the selected data server based on the address transmitted by the first transmission means. Providing acquisition means to The data server is the central server In the second transmission means A data management system comprising means for storing the transmitted data is provided.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.
<System configuration>
FIG. 1 is a schematic diagram of a network system capable of data management according to an embodiment of the present invention.
[0012]
In this network system, an application server group 11 and a client terminal group 12 are communicably connected via a network 10 such as the Internet configured by various communication lines. In this embodiment, a disaster information database (server) 13 that provides disaster information is connected to the network 10.
[0013]
This network system mainly provides a service for managing various data owned by a user (hereinafter also simply referred to as user data) by the application server group 11.
[0014]
The application server group 11 includes a central server 111 that mainly implements the data management service of the present embodiment, and a plurality of data servers 112 for storing data owned by the user. In FIG. 1, only two data servers 112 are exemplarily shown, but it goes without saying that there may be more data servers or a single data server depending on the embodiment.
[0015]
On the other hand, the client terminal group 12 includes a remote printer 121, a personal computer 122 that is a wired terminal, and a mobile phone 123 that is a wireless terminal. A digital camera 125 can be connected to the personal computer 122 or the mobile phone 123, and image data captured by the user with the digital camera 125 can be transmitted to the network 10.
[0016]
The central server 111 and the data server 112 can be configured from general-purpose server computers.
[0017]
As a characteristic configuration, the central server 111 stores a plurality of types of encryption algorithm programs for encrypting user data in an executable manner, and also has a member profile, a data server profile, and a stored data list, Is remembered.
[0018]
In the member profile, information related to a user (member) who receives the data management service of this embodiment is recorded. FIG. 5 is a diagram illustrating an example of a member profile. The member profile in FIG. 5 includes an ID No. identifying each member. In addition, a password for member authentication and a registered address of the member are recorded. The registered address is arbitrarily set by the member at the time of member registration, and includes the member's address, work place, and the like. This registered address can serve as a reference for selecting a data server that the user desires to store in the system. Although not shown, the member profile also records, for example, the e-mail address of the member.
[0019]
In the data server profile, information related to a data server that is a storage location of user data in the present embodiment is recorded. FIG. 6 is a diagram illustrating an example of a data server profile. In the data server profile of FIG. 6, an address for identifying each data server, an authentication password for authentication for eliminating improper servers such as impersonation, and an installation address indicating the installation location of the data server are recorded. Has been. The installation address is used when selecting a data server for storing user data.
[0020]
In the storage data list, storage information of user data for each member is recorded. FIG. 7 is a diagram illustrating an example of the stored data list. The stored data list of FIG. 7 includes an ID No. identifying each member. A user data file name that identifies each user data, a storage destination server address that identifies a data server where the user data is stored, and an encryption algorithm and an encryption key that are information related to user data encryption, which will be described later And the storage date of the user data.
[0021]
Each data server 112 stores the above-described member profile so as to correspond to a transmission request from the member for the stored user data. Further, in order to perform authentication with the central server 111, an authentication password recorded in the data server profile is also stored.
[0022]
Next, FIG. 8 is a functional block diagram of the digital camera 125.
[0023]
The digital camera 125 includes an imaging unit 1401, an image processing unit 1402 that converts an image captured by the imaging unit 1401 into electronic data, and encryption / decryption of data based on a predetermined encryption algorithm / encryption key. An encryption processing unit 1403 for converting the electronic image data into visible image data, a control CPU 1405 for controlling the digital camera 125, and a removable memory unit 1406 for storing and storing the digitalized image. 1, a communication interface 1407 that manages communication of a local link with a client terminal such as the personal computer 122 or the mobile phone 123 of FIG. IC card interface 1409 that controls the output and the output control unit 1 It includes a display 1410 for displaying an image based on the converted visible image data at 04, the. The IC card 124 functions as a user identification module for identifying whether or not the user is a member who can receive the data management service of the present embodiment.
[0024]
Next, FIG. 9 is a functional block diagram of the remote printer 121 of FIG.
[0025]
The remote printer 121 includes a local input interface 1501 that receives local image data from a scanner, a personal computer, etc., an image processing unit 1502 that converts the input image data into a predetermined format, and a predetermined encryption algorithm / encryption data. The encryption processing unit 1503 for encrypting / decrypting based on the encryption key, the output control unit 1504 for controlling the printer engine 1510 while converting the image data into visible image data, and the control CPU 1505 for controlling the remote printer 121 A detachable memory unit 1506 for storing and storing electronic data images, a communication interface 1507 for controlling communication with the network 10 in FIG. 1, a memory 1508 for storing a control program for the remote printer 121, and the IC card 1 Includes an IC card interface 1509 which controls communication between the 4, a printer engine 1510 performs printing in accordance with control of the output control unit 1504, the.
[0026]
Next, FIG. 10 is a diagram showing an example of a logical information storage hierarchy model of the IC card 124. In the present embodiment, a smart card with a terminal conforming to ISO7816 is assumed as the IC card 124.
[0027]
In this hierarchical model, the MF (Master File) 1601, which is the highest hierarchy of the logical file structure of the IC card 124, the highest DF (Dedicate File) 1603 and 1604 immediately below the MF 1601, and the highest DFs 1603 and 1604 are shown. There is an uppermost EF (Elementary File) 1602 which is an element file for storing information regarding. In this embodiment, a unique value is assigned to each service provider as an application ID for identifying the highest level DF (DF for service provider), and the service provided by the service provider below the DF (1603, 1604). Of the DF (service application DF) to which a unique application ID is assigned for each menu, various types of information (this embodiment) used in this application below the DF (1605, 1606) related to the user data storage service of this embodiment , The data storage server address assigned to each user data storage service of each service provider and the encryption key information necessary for decrypting the data stored on the data storage server are stored. (1607-1612) adopts file hierarchy structure .
[0028]
If an information format agreed by each service provider is used by an alliance of a plurality of service providers, a DF (1605, 1606) related to the user data storage service is defined as a single DF, and the user data Even if a DF to which a single application ID is assigned as a storage service is adopted as the highest DF, the file hierarchical structure of this embodiment can be adopted.
[0029]
It should be noted that the file hierarchical structure information storage function realized by the IC card 124 can be directly incorporated into the remote printer 121, the personal computer 122, or the mobile phone 123 so that the IC card 124 is not used. Needless to say, is feasible.
[0030]
Hereinafter, data management processing executed on the system having such a configuration will be described.
<Storing user data>
A process when the user stores image data of an image captured by the digital camera 125 via the client terminal (here, the mobile phone 123) in the data server 112 will be described. FIG. 2 is a flowchart showing such data storage processing.
[0031]
In step S <b> 1, the mobile server 123 accesses the central server 111 and transmits a request for storing image data captured by the digital camera 125. In this embodiment, since the data management service is provided only to members registered in advance, the storage request includes the ID No. of the user. And information for authenticating whether or not the member is a member, such as a password. These pieces of information are acquired from the IC card 124.
[0032]
In step S <b> 11, the central server 111 executes reception processing in response to a storage request from the mobile phone 123. In this reception process, the central server 111 performs a user authentication process with reference to the member profile shown in FIG. 5 to determine whether the storage request is made by a regular member. If the user authentication is successful, the member permits transfer of the image data requesting storage, and if the user authentication fails, the communication with the mobile phone 123 is disconnected.
[0033]
If the user authentication is successful, image data captured by the digital camera 125 is transmitted from the mobile phone 123 to the central server 111 in step S2.
[0034]
Next, in step S12, the central server 111 temporarily stores the received user data. At this time, it is possible to determine whether or not there is a data error being transferred based on a checksum of the received user data, and when the data error is detected, the mobile phone 123 can be requested to retransmit the user data.
[0035]
In step S13, the central server 111 accesses the disaster information database 13 and requests disaster information. On the other hand, the disaster information database 13 transmits disaster information to the central server 111 (step S41).
[0036]
The disaster information includes, for example, disaster prediction information such as typhoons and earthquakes, and the central server 111 checks the disaster occurrence rate for each region. For example, in addition to disaster information provided by the Japan Meteorological Agency and private contractors on the network, the rate of disaster occurrence is a regional rate for non-life insurance (fire insurance, earthquake insurance, etc.) managed by non-life insurance companies. It is also possible to check from information.
[0037]
Further, in the present embodiment, the central server 111 acquires the disaster information every time there is a storage request from the member. However, this information is periodically acquired and stored in the central server 111. Thus, the process of step S13 can be omitted.
[0038]
Next, in step S14, the central server 111 selects a data server for storing user data from the data server 112 with reference to the data server profile of FIG. In the present embodiment, two data servers are selected. For this purpose, first, the central server 111 refers to the member profile of the user (member) who requested the storage, and acquires the registered address.
[0039]
Next, the central server 111 refers to the data server profile, selects one data server installed in an area or place other than the registered address of the user, such as a prefecture, a municipality, and the like. Let it be server (A). Next, out of all the data servers 112, one data server located in an area or place where the predicted occurrence rate of the disaster examined earlier is equal to or less than a predetermined threshold is selected and stored as user data. It is assumed that the previous data server (B).
[0040]
In this case, the central server 111 accesses the data server after selecting the data server, authenticates the selected data servers A and B with reference to the data server profile, and is not an improper server such as impersonation. You may make it confirm that. As a result of such data server authentication, if the selected data server is an unauthorized server, cancel the data server selection, select the data server again, and record the unauthorized server. In the subsequent data server selection, the priority may be lowered. By performing such server authentication, the reliability of the system and service can be improved.
[0041]
Next, in the present embodiment, as will be described later, user data subjected to different encryption is stored in the data servers A and B, so that encryption algorithms for the respective encryption / decryption are stored. And an encryption key. In this embodiment, since user data is stored in two data servers, two types of encryption algorithms are used, two types of encryption keys are used, or one type of encryption algorithm is used. This encryption key is used.
[0042]
Next, in step S15, the central server 111 stores the file name for specifying the user data stored in the mobile phone 123, the addresses of the data servers A and B that are user data storage destinations, and information on the encryption algorithm. And the encryption key and the storage condition are transmitted, and the storage data list shown in FIG. 7 is also updated. Needless to say, the storage condition may be transmitted after the user data is stored in the data server.
[0043]
In step S <b> 3, the mobile phone 123 stores the storage condition transmitted from the central server 111 in the IC card 124 attached to the digital camera 125. After storage, communication between the mobile phone 123 and the central server 111 is disconnected.
[0044]
In step S16, the central server 111 encrypts user data. Encryption is performed for each of the data servers A and B by a separate encryption method according to the encryption algorithm and encryption key defined in step S14.
[0045]
In step S17, the central server 111 sequentially accesses the selected data servers A and B and transmits the encrypted user data to the data servers A and B, respectively. In steps S21 and S31, the data servers A and B store the user data transmitted from the central server 111. After storing, the process ends.
[0046]
Thus, in this embodiment, since data such as image data owned by the user can be stored in the data server 112 on the network, it is not necessary to store the data in the user terminal, and the memory Can be used effectively.
[0047]
In addition, even if the user does not perform a special operation for designating the data storage location, the user data is stored in a data server installed at a location different from the registered address of the user or in a location where the disaster occurrence rate is low. Since it is stored in the installed data server, important user data can be protected even when the registered address of the user is damaged by a disaster.
<Acquisition of stored data>
Next, processing when user data stored in the data server 112 is acquired by a client terminal (here, referred to as a remote printer 121) will be described. FIG. 3 is a flowchart showing the data acquisition process. This process is started when the user attaches the IC card 124 to the remote printer 121, specifies user data, and instructs the remote printer 121 to acquire the data.
[0048]
In step S101, the remote printer 121 stores the storage conditions such as the address of the data server 112 storing the user data instructed from the IC card 124, the encryption key, the encryption algorithm information, and the member ID No. Read the password. In step S102, the remote printer 121 accesses the data server (112) at the address read in step S101, and reads the member ID No. read from the IC card 124. The user data transmission request is transmitted by specifying the file name together with the password.
[0049]
In step S111, the data server (112) performs reception processing in response to a transmission request from the remote printer 121. In this reception process, the data server (112) performs a user authentication process for determining whether or not the transmission request is made by a regular member. If the user authentication is successful, the transfer of the user data requested for transmission is permitted, and if the user authentication is unsuccessful, the communication with the remote printer 121 is disconnected. If the user authentication is successful, user data is transmitted from the data server (112) to the remote printer 121 in step S112, and communication with the remote printer 112 is disconnected. The remote printer 121 receives user data from the data server (112), determines the validity of the user data transferred by a checksum or the like, and requests retransmission of the user data when an error is detected. It can also be.
[0050]
In step S103, the remote printer 121 uses the encryption processing unit 1503 to decrypt the transferred user data using the encryption key and encryption algorithm read from the IC card 124. In step S104, the decrypted user data is printed out and the process ends.
[0051]
As described above, each user can acquire user data stored in the data server 112. In this embodiment, the data server 112 is directly accessed from the client terminal and a transmission request for stored user data is made. However, a user data transmission request is made via the central server 111. May be.
<Check tampering with stored data>
In the present embodiment, in order to improve the security of the user data stored in the data server 112, the central server 111 periodically checks whether the stored user data has been tampered with.
[0052]
The central server 111 periodically (for example, every day) checks the storage date of each data recorded in the storage data list of FIG. 7, and falsifies user data that has passed several days, weeks, or months from the storage date. The following processing is executed to check FIG. 4 is a flowchart showing the tampering check process.
[0053]
In step S201, the central server 111 sequentially accesses the data servers A and B in which user data to be checked is stored, and transmits a user data transfer request.
[0054]
In steps S <b> 211 and S <b> 221, the data servers A and B execute reception processing in response to the data transfer request from the central server 111. In steps S212 and S222, the data servers A and B transmit user data to the central server 111.
[0055]
In these processes, the central server 111 may authenticate the data server and confirm that these are not improper servers such as impersonation. As a result of such data server authentication, if the selected data server is an unauthorized server, the number of times it was determined to be an unauthorized server is recorded. You may make it notify a member via a terminal.
[0056]
Next, in step S202, the central server 111 decrypts the user data transmitted from the data servers A and B based on the encryption algorithm and the encryption key recorded in the stored data list of FIG.
[0057]
In step S203, the central server 111 compares the decrypted user data and determines whether or not they match. If the user data matches, the process ends and communication with the data servers A and B is disconnected. If they do not match, the process advances to step S205 to instruct the data servers A and B to execute error detection processing for determining whether or not there is an error in the transferred data. This is because the user data may not match because of an operational error of the data server 112 in addition to tampering.
[0058]
In steps S213 and S214, the data servers A and B execute error detection processing in accordance with instructions from the central server 111. In the present embodiment, each of the data servers A and B executes a memory scan (local check) of a memory in which user data is stored, detects an error, and corrects an error location if correction is possible.
[0059]
In steps S214 and S224, the data servers A and B notify the central server 111 of the result of the error detection process, respectively. If there is an error, the corrected user data is also transmitted.
[0060]
In step S206, the central server 111 receives error detection processing results from the data servers A and B, and determines whether or not there is an error. If there is an error, the process returns to step S202 and the above-described processing is executed using the corrected user data. If there is no error, it is determined on the data server A or B that the user data has been tampered with for some reason, and this is notified to the user's client terminal by e-mail or the like (step S207). Further, the altered part can be stored in the memory in the central server 111 and notified according to the user's request.
[0061]
As described above, since the application management server 111 autonomously and periodically checks the data validity on the data server 112, the validity of the user data stored and stored on the data server 112 by the member ( It is possible to greatly reduce the labor for confirming that there is no falsification.
[0062]
Note that the present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, and a printer), and a device (for example, a copying machine and a facsimile device) including a single device. You may apply to.
[0063]
Also, an object of the present invention is to supply a storage medium (or recording medium) that records a program code of software that realizes the functions of the above-described embodiments to a system or apparatus, and to perform computer (or CPU or CPU) of the system or apparatus. Needless to say, this can also be achieved when the MPU) reads and executes the program code stored in the storage medium. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.
[0064]
Furthermore, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function is based on the instruction of the program code. It goes without saying that the CPU or the like provided in the expansion card or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.
[0065]
【The invention's effect】
As described above, according to the present invention, electronic data owned by a user can be suitably managed.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a network system according to an embodiment of the present invention.
FIG. 2 is a flowchart showing data storage processing executed in the network system of FIG.
FIG. 3 is a flowchart showing data acquisition processing executed in the network system of FIG. 1;
4 is a flowchart showing falsification check processing executed in the network system of FIG. 1. FIG.
FIG. 5 is a diagram showing an example of a member profile.
FIG. 6 is a diagram illustrating an example of a data server profile.
FIG. 7 is a diagram illustrating an example of a stored data list.
8 is a functional block diagram of the digital camera 125. FIG.
9 is a functional block diagram of a remote printer 121. FIG.
10 is a diagram showing an example of a logical information storage hierarchy model of an IC card 124. FIG.

Claims (14)

A data management method by a network system including a central server, a plurality of data servers, and a client terminal,
Receiving means of the central server includes a reception step of receiving a data storage request by the user from the client terminal,
A selection step in which the means for selecting the central server selects a data server installed in an area having a certain relationship with the area set by the user who has made the data storage request from the plurality of data servers ;
The transmission step of the central server transmits the address of the data server selected in the selection step to the client terminal, and
Storage means of the central server is, for the selected data server by the selection step, a storing step of storing and transmitting data relating to said data storage request,
The acquisition means of the client terminal accesses the selected data server based on the address transmitted in the transmission step, so that the data stored in the data server can be stored without going through the central server. An acquisition process to acquire;
A data management method characterized by comprising : In the selection process,
The data management according to claim 1, wherein the central server selection means selects the data server installed in an area other than the area set by the user from the plurality of data servers. Method. In the selection process,
The central server selection means selects a plurality of data servers for storing the data from the plurality of data servers ,
In the storing step,
To each of the data server described above selected to transmit the data according to the data storage request, the data management method according to claim 1, characterized in that to store. Furthermore,
The search means of the central server includes the steps of acquiring disaster information from a disaster information database that provides disaster information, and searching for a region with a low disaster occurrence rate based on the acquired disaster information,
In the selection process,
The central server selecting means is , among the plurality of data servers, at least the data server installed in an area other than the area set by the user, and the disaster server with a low disaster occurrence rate. The data management method according to claim 3, wherein a data server is selected. Furthermore,
The encryption means of the central server includes an encryption step of encrypting data relating to the data storage request;
4. The data management method according to claim 3, wherein, in the storing step, the data encrypted in the encryption step is transmitted and stored to each of the selected data servers. Furthermore,
The data acquisition means of the central server periodically acquires the encrypted data from each of the selected data servers;
The central server data decoding means, and a step of respectively decode the acquired data,
Tampering check means of the central server is by comparing each data the decoded, and determining whether the data stored in the data server has been tampered with,
The data management method according to claim 5, further comprising: Furthermore,
An encryption step in which the encryption means of the central server encrypts data related to the data storage request;
The decryption means of the client terminal has a decryption step of decrypting the encrypted data,
In the storing step, the data server selected in the selection step is transmitted and stored by transmitting the data encrypted in the encryption step,
In the transmission step, the address of the data server selected in the selection step and a key for decrypting the data encrypted in the encryption step are transmitted to the client terminal,
In the obtaining step, the encrypted data stored in the data server without going through the central server is accessed by accessing the selected data server based on the address transmitted in the sending step. Get the data,
2. The data management method according to claim 1, wherein in the decryption step, the encrypted data acquired in the acquisition step is decrypted using the key transmitted in the transmission step. . The condition storage means of the client terminal further comprises a condition storage step of storing the address transmitted in the transmission step in a card ,
In the acquisition step, data stored in the data server is acquired without going through the central server by reading the address from the card and accessing the selected data server based on the read address. the data management method according to claim 1, characterized in that. The client terminal condition storage means further comprises a condition storage step for storing the address and the key transmitted in the transmission step in a card,
In the acquisition step, the encryption is stored in the data server without going through the central server by reading the address from the card and accessing the selected data server based on the read address. Retrieved data,
In the decoding step, reading out the key from the card, using the key read the, according to claim 7, wherein the decoding the encrypted data acquired by said acquisition step Data management method. The client terminal that stores the address in the card in the condition storing step and the client terminal that acquires the data stored in the data server by reading the address from the card in the acquiring step are different devices. 10. The data management method according to claim 8 or 9 , wherein: 11. The client terminal that reads the address from the card and acquires data stored in the data server in the acquiring step is a printer that can be loaded with the card. The data management method according to item 1 . Accepting means for accepting a data storage request from a user transmitted from a client terminal via a communication line;
A selection means for selecting a data server installed in a different area from the address of the user who made the data storage request from among a plurality of data servers ,
Transmitting means for transmitting the address of the data server selected by the selecting means to the client terminal;
For the selected data server by said selecting means, and storing means for storing transmit data according to the data storage request via the communication line,
A server characterized by comprising: Computer
Accepting means for accepting a data storage request sent from a client terminal via a communication line by a user;
A selection means for selecting a data server installed in a different area from the address of the user who made the data storage request from a plurality of data servers ,
Transmitting means for transmitting the address of the data server selected by the selecting means to the client terminal;
For the selected data server by said selecting means, storing means for storing transmit data according to the data storage request via the communication line,
Program to function as. A data management system including a central server, a client terminal, and a plurality of data servers that can communicate with each other via a communication line,
The central server is
Accepting means for accepting a data storage request sent by the user transmitted from the client terminal;
A selecting means for selecting a data server installed in an area different from the address of the user who made the data storage request from the plurality of data servers;
First transmission means for transmitting the address of the data server selected by the selection means to the client terminal;
For the selected data server by said selecting means, and a second transmission means for transmitting data relating to said data storage request,
The client terminal is
Obtaining means for obtaining data stored in the data server without going through the central server by accessing the selected data server based on the address transmitted by the first transmitting means. ,
The data server is
A data management system comprising means for storing the data transmitted by the second transmission means of the central server.

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