JP5365251B2 - File storage system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust a preservation period of a backup file stored in a storage device different from a computer device providing use environment of a file according to a use situation of the file in the computer device. <P>SOLUTION: In this system for storing a backup of the file into the storage device different from a terminal device providing the use environment of the file, identification information for identifying the file is generated from contents of the file, environment management information for associating the identification information and the use environment is stored, the backup of the file is stored associatively to the identification information, operation in the use environment is detected, an operation history thereof is stored associatively to the use environment, a deletion condition of the file is set according to an importance level of the file acquired based on the operation history when the file is deleted, and the file corresponding to the accomplished deletion condition is deleted from the storage device. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a file storage system that backs up a file stored in a terminal device.

  There has been proposed a system for storing a file used in a computer apparatus in a storage device shared by a plurality of computer apparatuses.

  Patent Document 1 discloses an electronic filing device that stores a file used in a client device connected via a network. An electronic filing device disclosed in Patent Document 1 includes a registration unit for registering a document, a browsing unit for browsing the document registered by the registration unit, a document access frequency by the browsing unit, and a document Management means for managing the free capacity of various resources capable of storing the document, and determining the optimum resource for storing the document from the access frequency of the document by the browsing means and the free capacity of the various resources, and Moving means for moving to an optimal resource. According to the configuration of the electronic filing apparatus disclosed in Patent Document 1, it is said that resources can be effectively used in consideration of document access frequency and resource free capacity when managing documents. .

  Further, in a system for storing a backup file of a file used in a computer device, a system has been proposed for the purpose of effectively utilizing the storage capacity in the computer device by providing a retention period for the stored backup file. ing.

  Patent Document 2 discloses a file storage management device. When the file storage management device disclosed in Patent Document 2 temporarily stores an edited file, the file storage management device stores temporary storage management information indicating the temporary storage period of the file and the processing after the storage period ends. Furthermore, the file management device disclosed in Patent Document 2 periodically checks whether or not the temporary storage period of the temporarily stored file has ended, and temporarily stores the temporary storage file for which the temporary storage period has ended. The processing set in the management information file 33 is performed.

JP 2001-14191 A JP 2005-182173 A

  The electronic filing device disclosed in Patent Document 1 provides a file used in a client device via a network in order to collect file access frequencies. That is, when using the file, the client device disclosed in Patent Literature 1 needs to download the file stored in the electronic filing device via the network.

  Therefore, in the technique disclosed in Patent Document 1, in a situation where downloading from an electronic filing device cannot be performed via a network, operations such as file browsing and editing cannot be performed, and convenience is reduced.

  However, when using a file (local file) stored in a storage device included in a computer device that provides a file usage environment to a user, the above-described decrease in convenience does not occur, but a remote electronic filing device does not occur. Cannot organize files based on useful information such as file access frequency.

  In addition, the file storage management device disclosed in Patent Document 2 sets a temporary storage period of a file when temporarily storing the file. For this reason, it is difficult to adjust the temporary storage period according to the importance of the file in a state where the contents of the file to be temporarily stored are not grasped.

  If the inventors of this application are engaged in the development of products in the technical field to which the file storage system disclosed in this application belongs, it is convenient if the backup retention period of the file can be adjusted according to the importance of the file. We focused on the improvement of sex.

  The inventors of the present application have further found that a value suitable for the contents of a file can be set by determining the importance of the file according to the usage status of the file.

  The inventors of the present application can associate the usage status of a file collected in a computer device that provides a user with a file usage environment with a backup file stored in a file storage device different from the computer device. It has been recognized that the above-mentioned problems of the prior art are solved and it is useful for organizing backup files in the file storage device.

  Accordingly, the present invention disclosed in the present application provides a computer in a file storage system that stores a backup of a file used in a computer device that provides a file usage environment in a storage device connected to the computer device via a network. It is an object of the present invention to apply a file storage system that can adjust the backup retention period according to the usage status of a file in the apparatus.

A file storage system according to an embodiment of the present invention disclosed below provides backup of a file used in a computer device that provides a file use environment, which is an environment that enables operations on files, via a computer device and a network. A file storage system for storing in a connected storage device, wherein an identification information generation unit that generates file identification information for identifying a file from a file content using a hash function, and a backup of the file identified by the file identification information Is detected when the file operation detection unit detects a file operation in a file usage environment , a backup storage unit that stores the file identification information in association with file identification information, a file operation detection unit that detects the operation of the file, and The operation history showing the operation contents of the selected file The operation history storage unit that stores the file in correspondence with the file identification information of the detected file for each usage environment of the issued file, and the file identification of the file when the operation content of the detected file is file deletion The importance acquisition unit that acquires the importance of the file based on the operation history stored in the operation history storage unit in association with the information, and the target of the detected operation based on the acquired importance A deletion condition setting unit that sets a deletion condition of a file in association with the file identification information of the file, a condition monitoring unit that determines the fulfillment of the set deletion condition, and a deletion that is determined to be fulfilled by the condition monitoring unit A deletion execution unit for deleting a file corresponding to the condition from the backup storage unit;

  The present invention disclosed in the present application is a file storage system for storing a backup of a file used in a computer device that provides a file usage environment in a storage device connected to the computer device via a network. The backup retention period can be adjusted according to the file usage status.

The figure which showed the structural example of the system which concerns on a present Example The figure which showed the example of a structure of the program run in a terminal device The figure which showed the example of a structure of the program run in a file storage apparatus An example of the data structure of operation history information and an example of its contents Example of data structure of protected area management information and its contents Diagram showing an example of the data structure of the registration request signal Diagram showing an example of the data structure of the delete request signal The figure which showed the example of the data structure of a backup reference request signal Diagram showing an example of the data structure of the download request signal Example of data structure of file management information and its contents example The figure which showed the example of the data structure of the terminal device management information, and the example of the contents Figure showing an example of the data structure of backup list information Figure showing an example of the data structure of download file information The figure which showed the typical structure of the file system comprised by the memory | storage part of a terminal device Figure showing an example of the flow of processing when registering a file Figure showing an example of the flow of processing during file operations Figure showing an example of the flow of processing during a backup reference request operation Figure showing an example of the flow of condition monitoring processing Figure showing an example of the contents of the file list screen The figure which showed the structural example of the program performed in the terminal device which concerns on Example 2. FIG. The figure which showed the structural example of the program performed in the file storage apparatus which concerns on Example 2. FIG. Diagram showing an example of the data structure of the update request signal The figure which showed the example of the data structure of the file management information based on Example 2, and the example of the content The figure which showed the example of the flow of the process at the time of the file operation which concerns on Example 2 (the 1) The figure which showed the example of the flow of the process at the time of the file operation which concerns on Example 2 (the 2) The figure which showed the example of the flow of the condition monitoring process which concerns on Example 2.

[1. System configuration)
FIG. 1 shows a configuration of a system according to the present embodiment. The system illustrated in FIG. 1 includes a terminal device 100 and a file storage device 200. Note that the configuration of each apparatus shown in FIG. 1 does not necessarily have to be physically configured as illustrated. In other words, the specific form of distribution / integration of each device is not limited to that shown in the figure, and all or a part thereof may be functionally or physically distributed or arbitrarily distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured.

  The terminal device 100 and the file storage device 200 shown in FIG. 1 are connected to a predetermined protocol such as TCP / IP (Transmission Control Protocol / Internet Protocol) and UDP / IP (User Datagram Protocol / Internet Protocol) via the network 300. Can be used for communication.

  The terminal device 100 shown in FIG. 1 is exemplified by a desktop personal computer, a notebook personal computer, and the like. As an example of the file storage device 200 shown in FIG. 1, a server device configured using a general-purpose computer, NAS (Network Attached Storage), and the like can be cited. The terminal device 100 can transmit the file stored in the storage unit 102 included in the terminal device 100 to the file storage device 200. The file storage device 200 can receive a file transmitted from the terminal device 100 and store the received file in the storage unit 202 included in the file storage device 200. With the above-described function, the terminal device 100 can store the backup of the file stored in the storage unit 102 included in the terminal device 100 in the storage unit 202 of the file storage device 200.

  FIG. 14 shows a schematic structure of a file system configured in the storage unit 102 of the terminal device 100. The file system shown in FIG. 14 has a system area T1031, a work area T1032, a protection area T1033, and a general area T1034.

  A system area T1031 shown in FIG. 14 is an area in which various data such as programs and setting information necessary for operating the operating system are stored.

  A work area T1032 shown in FIG. 14 shows a work area for storing temporary files and the like created in the course of program execution.

  A protection area T1033 illustrated in FIG. 14 indicates an area for storing a file to be backed up to the file storage apparatus 200 according to the present embodiment. The file stored in the protection area T1033 is copied to the storage unit 202 of the file storage device 200 via the network 300 by the program process according to this embodiment executed in the terminal device.

  A general area T1034 shown in FIG. 14 is an area for storing files that are used by the user of the terminal apparatus 100 and that are not to be backed up to the file storage apparatus 200 according to the present embodiment.

  With reference to FIG. 14, a process of performing backup according to the present embodiment will be described using mail browsing software executed in the terminal device 100 as an example.

  First, it is assumed that mail browsing software executed in the terminal device 100 receives a mail with a file attached thereto via the network 300. The file attached to the mail received by the mail browsing software is stored in the work area T1032 configured in the storage unit 102 (S001). A file F001 shown in FIG. 14 indicates a file stored in the work area T1032.

  The user of the terminal device 100 moves the file F001 stored in the work area T1032 to the protection area T1033 as necessary (S002). A file F002 shown in FIG. 14 indicates a file moved to the protection area T1033.

  The terminal device 100 detects the file F002 moved to the protection area T1033 and transmits the file F002 to the file storage device 200.

  The user of the terminal device 100 can use the file F002 stored in the protection area T1033 even after transmitting the file F002 to the file storage device 200. The terminal device 100 detects the use of the file F002 by the user and collects a log relating to the usage status.

  Furthermore, the user of the terminal device 100 can delete the file F002 stored in the protection area T1033 from the protection area T1033 as necessary. For example, the file F002 stored in the protection area T1033 can be moved to the general area T1034 and logically or physically deleted from the storage unit 102. The terminal device 100 detects the deletion of the file F002 from the protection area T1033, and determines the importance of the file F002 based on the usage status regarding the file F002. The terminal device 100 determines the erasure timing of the backup file of the file F002 stored in the file storage device 200 according to the importance of the file F002. The terminal device 100 notifies the file storage device 200 of the backup timing of the backup file of the file F002 via the network 300.

  The file storage device 200 controls the time when the backup file of the file F002 is deleted from the storage unit 202 based on the deletion timing received from the terminal device 100.

The user of the terminal device 100 causes the terminal device 100 to acquire the backup file of the file F002 via the network 300 while the backup file of the file F002 is being stored in the storage unit 202 of the file storage device 200. Thus, the backup file of the file F002 can be used.
[2. Configuration of terminal device]
Next, the configuration of the terminal device 100 according to the present embodiment will be described. A terminal device 100 illustrated in FIG. 1 includes a CPU (Central Processing Unit) 101, a storage unit 102, a display unit 103, an operation unit 104, and a communication unit 105.

  The CPU 101 is connected to each hardware unit of the terminal device 100 via an internal communication line, and executes predetermined processing according to a program procedure. For example, the CPU 101 decodes an instruction register (Instruction Register) that temporarily stores an instruction read from the storage unit 102 and a machine language instruction (binary number) stored in the instruction register, and the terminal device 100 according to the instruction. Instruction decoder circuit (Instruction Decoder) that controls each part of the system, arithmetic circuit (Arithmetic Logic Unit) that performs operations such as addition, subtraction, and numerical comparison according to the control from the instruction decoding circuit, data to be operated and results of operations, etc. An accumulator that temporarily stores the address, an address register that stores the address of the storage area that the storage unit 102 that the CPU 101 reads and writes, and a storage unit 102 that stores an instruction to be executed next It consists of a program counter (Program Counter) indicating the address of the storage area.

  The storage unit 102 includes, for example, a main storage unit and an auxiliary storage unit. The main storage unit of the storage unit 102 stores data generated by the execution of the CPU 101, data read from the auxiliary storage unit, and the like. For example, a semiconductor memory such as SDRAM (Synchronous Dynamic Random Access Memory) or SRAM (Static Random Access Memory) can be used.

  The auxiliary storage unit of the storage unit 102 stores information in the nonvolatile storage medium in response to a write command received from the CPU 101, and reads and outputs the information stored in the nonvolatile storage medium in response to a read command received from the CPU 101. . For example, magnetic recording devices such as HDD (Hard Disk Drive), non-volatile semiconductor storage devices such as SSD (Solid State Disk), CD-ROM (Compact Disc-Read Only Memory), DVD-ROM (Digital Versatile Disk- An optical disk device that reads a signal recorded on an optical disk medium such as Read Only Memory can be used.

  The display unit 103 causes a display device such as a liquid crystal display device to output information corresponding to a control command from the CPU 101. The display device may be configured to be connected to the terminal device 100 using an internal communication line provided in the terminal device 100 and integrated with the terminal device 100, or a D-Sub (D-Subminiature) 15 pin cable or the like. It is good also as a structure connected to the terminal device 100 using.

  The operation unit 104 receives user operations. The operation unit 104 outputs a signal corresponding to the user's operation to the CPU 101 via the internal communication line. For example, as the operation unit 104, an input button, a touch panel configured integrally with a display device, or the like can be used.

  The communication unit 105 transmits and receives signals to and from the file storage device 200 via the network 300. For example, it is configured using a network interface card.

  FIG. 2 shows a configuration of a program executed in the terminal device 100 according to the present embodiment. 2 includes a file storage unit PG100, a registration operation detection unit PG101, an identification information generation unit PG102, a registration request execution unit PG103, a backup reference operation detection unit PG104, and a backup. Reference request execution unit PG105, backup list information acquisition unit PG106, backup list information display unit PG107, download request execution unit PG108, file operation detection unit PG109, importance level acquisition unit PG110, deletion condition determination unit PG111, , A deletion request execution unit PG112, operation history information T101, and protected area management information T102.

  A file storage unit PG100 illustrated in FIG. 2 operates the CPU 101 as a component that stores a file in the storage unit 102 or extracts a file stored in the storage unit 102.

  The registration operation detection unit PG101 illustrated in FIG. 2 operates the CPU 101 as a component that detects a file registration operation in a file usage environment provided by the terminal device 100. Here, as an example of a use environment of a file provided by the terminal device 100, a file system function included in an operating system executed in the terminal device 100 can be cited. For example, the registration operation detection unit PG101 operates the CPU 101 as a component that detects a file registration operation in the protection area T1033 configured in the storage unit 102. Note that the usage environment of the file provided by the terminal device 100 may be distinguished for each terminal device 100 or for each user of the terminal device 100.

  The identification information generation unit PG102 shown in FIG. 2 uses the CPU 101 as a component that gives identification information for identifying the contents of the file to be registered by the registration operation detection unit PG101. Make it work. Note that the identification information generation unit PG102 may operate the CPU 101 as a configuration that adds identification information for identifying the file to the file stored in the storage unit 102 at an arbitrary timing. It should be noted that the content of the file based on the identification information generated by the process of the identification information generation unit PG102 need only be able to distinguish the content of a specific file from the content of another file, It is not always necessary to be able to grasp it.

  The registration request execution unit PG103 illustrated in FIG. 2 generates a registration request signal T103 indicating a request for registering a file that is the target of the registration operation detected in the process of the registration operation detection unit PG101 in the file storage device 200. As a component to be transmitted using the communication unit 105, the CPU 101 is operated.

  The backup reference operation detection unit PG104 illustrated in FIG. 2 operates the CPU 101 as a component that detects an operation for requesting reference to the backup stored in the file storage device 200.

  The backup reference request execution unit PG105 shown in FIG. 2 outputs a remote reference request signal for requesting a list of backups stored in the file storage device 200 when a backup reference operation is detected by the process of the backup reference operation detection unit PG104. The CPU 101 is operated as a component to be transmitted to the file storage device 200 using the communication unit 105.

  The backup list information acquisition unit PG 106 illustrated in FIG. 2 operates the CPU 101 as a component that acquires list information indicating a list of backups stored in the file storage device 200 using the communication unit 105.

  The backup list information display unit PG107 shown in FIG. 2 displays a screen for accepting selection of a file to be downloaded based on the list information acquired by the process of the list information acquisition unit PG106 on the display device using the display unit 103. The CPU 101 is operated as a component to be displayed.

  The download request execution unit PG 108 shown in FIG. 2 sends a download request signal for requesting download of a file that has been selected as a download target on the screen displayed by the process of the list information display unit PG 107 to the file storage device 200. The CPU 101 is operated as a component that acquires the file transmitted from the file storage device 200 using the communication unit 105.

  The file operation detection unit PG109 illustrated in FIG. 2 operates the CPU 101 as a component that detects a file operation in a file usage environment provided by the terminal device 100.

  When the operation content of the file detected by the process of the file operation detection unit PG109 is deletion of a file, the importance level acquisition unit PG110 shown in FIG. Based on the operation history stored in the section, the CPU 101 is operated as a component for acquiring the importance of the detected file.

  The deletion condition determination unit PG111 illustrated in FIG. 2 determines a deletion condition for a file that is an operation target detected by the process of the file operation detection unit PG109, based on the importance acquired by the process of the importance acquisition unit PG110. The CPU 101 is operated as a constituent element.

  The deletion request execution unit PG112 shown in FIG. 2 sends a deletion request signal for requesting deletion of the backup stored in the file storage device 200 based on the deletion condition determined by the process of the deletion condition determination unit PG109. The CPU 101 is operated as a component to be transmitted to the mobile station 200 using the communication unit 105.

  FIG. 4 shows the data structure of the operation history information T101. The operation history information T101 illustrated in FIG. 4 includes a file ID (T1011), an operation type (T1012), and an operation date / time (T1013).

  The file ID (T1011) illustrated in FIG. 4 indicates file identification information generated by the process of the identification information generation unit PG102.

  The operation type (T1012) illustrated in FIG. 4 indicates a type in which the operation contents of the file detected by the process of the file operation detection unit PG109 are classified. As an example of the operation type, “registration” indicating a file registration operation in the storage unit 102, “reference” indicating a reference operation of a file stored in the storage unit 102, and a file stored in the storage unit 102 For example, “deletion” indicating the deletion operation.

  The operation date and time (T1013) shown in FIG. 4 indicates the date and time when the file operation is detected by the process of the file operation detection unit PG109. The operation date / time (T1013) may be in seconds, minutes, hours, days, months, or years. These may be expressed in any combination.

  FIG. 5 shows the data structure of the protection area management information T102. The protected area management information T102 shown in FIG. 5 has a storage destination (T1021) and a file ID (T1022).

  The storage location (T1021) illustrated in FIG. 5 indicates the storage location of the file in the storage unit 102. As an example of the storage destination, an absolute path or a relative path indicating a file storage position in a file system function of an operating system executed in the terminal device 100 can be given.

  The file ID (T1022) shown in FIG. 5 is file identification information generated by the process of the identification information generation unit PG102, and the file identification information of the file stored at the storage location indicated by the storage destination (T1021). Show.

The program according to the above-described embodiment can be stored in the storage unit 102 of the terminal device 100. For example, this program is stored in a magnetic recording device such as an HDD (Hard Disk Drive) or a non-volatile semiconductor storage device such as an SSD (Solid State Disk), and a storage unit 102 according to the operating state of the CPU 101 of the terminal device 100. Are read into the main storage unit and the register of the CPU 101 and executed by the CPU 101. The program according to this embodiment can also be recorded on an optical disk medium such as a CD-ROM (Compact Disc-Read Only Memory) or a DVD-ROM (Digital Versatile Disk-Read Only Memory). In this case, the program can be executed in the terminal device 100 by reading the program according to the present embodiment from the optical disk medium using the optical disk device. The program according to the present embodiment can be distributed via a network such as the Internet. In this case, the program according to the present embodiment is received using the communication unit 105 of the terminal device 100 and is read into the main storage unit of the storage unit 102 or the register of the CPU 101 in accordance with the operation state of the CPU 101 of the terminal device 100. It is executed by. The above points are not applied only to the terminal device 100, and the same applies to the file storage device 200 according to the present embodiment.
[3. Configuration of file storage device]
Next, the configuration of the file storage device 200 according to the present embodiment will be described. A file storage device 200 illustrated in FIG. 1 includes a CPU (Central Processing Unit) 201, a storage unit 202, and a communication unit 203.

  The CPU 201 is connected to each hardware unit of the file storage device 200 via an internal communication line, and executes predetermined processing according to a program procedure. The CPU 201 decodes, for example, an instruction register (Instruction Register) that temporarily stores an instruction read from the storage unit 202, a machine language instruction (binary number) stored in the instruction register, and a file storage device according to the instruction Instruction decoding circuit (Instruction Decoder) that controls each part of 200, arithmetic circuit (Arithmetic Logic Unit) that performs operations such as addition, subtraction, and numerical comparison in accordance with control from the instruction decoding circuit, data to be operated and results of operations For example, an accumulator that temporarily stores information, an address register that stores the address of a storage area of the storage unit 202 that the CPU 201 reads and writes, and a storage unit 202 that stores an instruction to be executed next. It consists of a program counter (Program Counter) indicating the address of the storage area it has.

  The storage unit 202 includes a main storage unit and an auxiliary storage unit. The main storage unit of the storage unit 202 stores data generated by the execution of the CPU 201, data read from the auxiliary storage unit, and the like. For example, a semiconductor memory such as SDRAM (Synchronous Dynamic Random Access Memory) or SRAM (Static Random Access Memory) can be used.

  The auxiliary storage unit of the storage unit 202 stores information in the nonvolatile storage medium in response to a write command received from the CPU 201, and reads and outputs the information stored in the nonvolatile storage medium in response to a read command received from the CPU 201. . For example, a magnetic recording device such as an HDD (Hard Disk Drive) or a non-volatile semiconductor storage device such as an SSD (Solid State Disk) can be used.

  The communication unit 203 transmits and receives signals to and from the terminal device 100 via the network 300. For example, it is configured using a network interface card.

  FIG. 3 shows a configuration example of a program executed in the file storage device according to the present embodiment. The configuration example of the program shown in FIG. 3 includes a registration request reception unit PG201, a backup storage unit PG202, a backup reference request reception unit PG203, a backup transmission unit PG204, a deletion request reception unit PG205, a condition monitoring unit PG206, Deletability determination unit PG207, deletion execution unit PG208, file management information T201, and terminal device management information T202.

  3 receives the registration request signal T103 transmitted by the process of the registration request execution unit PG103 using the communication unit 203, and performs predetermined processing based on the content of the received registration request signal T103. CPU201 is operated as a component which performs.

  The backup storage unit PG202 shown in FIG. 3 stores the backup of the file indicated by the registration request signal T103 received by the process of the registration request receiving unit PG201 in association with the file identification information indicated by the registration request signal T103. As an element, the CPU 201 is operated.

  The backup reference request receiving unit PG203 illustrated in FIG. 3 receives the backup reference request signal T105 transmitted by the process of the backup reference request executing unit PG105 using the communication unit 203, and based on the content of the received backup reference request signal T105. The CPU 203 is operated as a component that executes predetermined processing.

  The backup transmission unit PG 204 illustrated in FIG. 3 includes a CPU 201 as a component that transmits the backup file indicated by the backup reference request signal T105 received through the process of the backup reference request reception unit PG 203 to the terminal device 100 using the communication unit 203. To work.

  3 receives the deletion request signal T104 transmitted by the process of the deletion request execution unit PG112 using the communication unit 203, and performs predetermined processing based on the content of the received deletion request signal T104. CPU201 is operated as a component which performs.

  The condition monitoring unit PG206 shown in FIG. 3 is a component that determines the fulfillment of the deletion condition determined by the process of the deletion condition determination unit PG109 indicated by the deletion request signal T104 received by the process of the deletion request reception unit PG205. The CPU 201 is operated.

  When it is determined that the deletion condition is satisfied by the process of the monitoring unit PG206, the deletion permission / inhibition determination unit PG207 illustrated in FIG. 3 is based on the presence / absence of another usage environment that uses the file corresponding to the determined deletion condition. Then, the CPU 201 is operated as a component that determines whether or not a file corresponding to the determined deletion condition can be deleted.

  The deletion execution unit PG208 shown in FIG. 3 operates the CPU 201 as a component that deletes the file corresponding to the deletion condition from the storage unit 202 when it is determined that deletion is possible in the process of the deletion possibility determination unit PG207.

  FIG. 10 shows the data structure of the file management information T201. The file management information T201 illustrated in FIG. 10 includes a file ID (T2011) and a storage destination (T2012).

  The file ID (T2011) illustrated in FIG. 10 indicates identification information that identifies the content of the backup file stored in the storage unit 202. For example, the file ID is a value corresponding to the file identification information generated by the process of the identification information generation unit PG102 executed in the terminal device 100. Note that the content of a file need only be able to distinguish the content of a specific file from the content of another file, and it is not necessary to specifically grasp the content of the specific file.

  The storage location (T2012) shown in FIG. 10 indicates the storage location in the storage unit 202 of the file identified by the file ID (T2011). As an example of the storage destination, an absolute path or a relative path indicating a file storage position in a file system function of an operating system executed in the file storage device 200 can be given.

  FIG. 11 shows the data structure of the terminal device management information T202. The terminal device management information T202 illustrated in FIG. 11 includes an environment ID (T2021), a file ID (T2022), a file name (T2023), and a deletion date / time (T2024).

  The environment ID (T2021) illustrated in FIG. 11 indicates identification information for identifying a use environment of a file provided by the terminal device 100.

  A file ID (T2022) illustrated in FIG. 11 indicates identification information for identifying a backup file stored in the storage unit 202.

  The file name (T2023) shown in FIG. 11 indicates the file name of the backup file identified by the file ID (T2022) in the usage environment identified by the environment ID (T2021). The file name (T2023) may be set to a value corresponding to the file name portion of the storage location indicated by the storage location (T1021) of the protected area management information T102 of the terminal device 100, or the storage location You may set the value corresponding to all.

In the deletion date and time (T2024) shown in FIG. 11, the deletion condition determined by the process of the deletion condition determination unit PG111 of the terminal device 100 indicated by the deletion request signal T104 received by the process of the deletion request reception unit PG205 is registered. The In the example illustrated in FIG. 11, an example in which the deletion date and time (T2024) is registered as the deletion condition is illustrated.
[4. Flow of processing during file registration]
FIG. 14 shows an example of the flow of processing when registering a file. First, the terminal device 100 monitors that a file is stored in the protection area T1033 configured in the storage unit 102, and detects that the file is stored or stored in the protection area T1033 (S101). ), Identification information of the file stored or stored in the storage unit 102 is generated (S102).

  For example, the CPU 101 of the terminal device 100 appropriately collects information on the files stored in the protected area T1033, and detects the newly stored file when updating the area management information T102 based on the collected information. be able to. For example, the CPU 101 of the terminal device 100 compares the collected file information with the contents already registered in the protection area management information T102, thereby effectively adding the protection area management information T102 out of the files indicated in the collected file information. Unregistered file information can be specified. Here, “substantially unregistered in the protection area management information T102” means that the value corresponding to the storage destination of the file indicated in the collected file information is not registered in the storage destination T1021 of the protection area management information T102, A case where the file ID (T1022) of the protection area management information T102 is not substantially registered corresponding to the value of the storage location of the file indicated in the collected file information.

  Further, the CPU 101 of the terminal device 100 monitors a signal indicating a write request to the storage unit 102 and determines whether or not the signal indicating the detected write request indicates a file write to the protection area T1033. It can be detected that a file is stored in the region T1033. When the CPU 101 of the terminal device 100 detects a signal indicating a write request to the protection area T1033, the CPU 101 collects information on the files stored in the protection area T1033. Further, the CPU 101 compares the collected file information with the storage destination (T1021) already registered in the protection area management information T102, and among the files indicated in the collected file information, the file not registered in the protection area management information T102 By specifying the information, a newly stored file can be specified.

  When the CPU 101 of the terminal device 100 detects the storage of the file in the protection area T1033, the CPU 101 identifies the newly added file with reference to the protection area T1033, and generates identification information for identifying the identified file ( S102). Here, the file has management information indicating the name and data length of the file, and a data block indicating the data of the file body. The CPU 101 of the terminal device 100 can use, for example, a hash value obtained based on the contents of the data block portion of the file as identification information. The CPU 101 of the terminal device 100 can use, for example, a hash function such as SHA-256, SHA-384, or SHA-512 as an algorithm for generating a hash value. When the hash function of SHA-256 is used, the hash value is 256 bits long. When the hash function of SHA-284 is used, the hash value is 384 bits long. When the hash function of SHA-512 is used, the hash value is 512 bits long.

  The CPU 101 of the terminal device 100 updates the protection area management information T102 using the storage location (including the file name) of the file detected in step S101 and the identification information generated in step S102. That is, the CPU 101 registers a value in the storage location (T1021) of the protected area management information T102 using the storage location of the file detected in step S101. Further, the CPU 101 registers the file ID (T1022) of the protection area management information T102 using the hash value generated in step S102.

  FIG. 5 shows an example of the contents of the protection area management information T102. 5 shows an example in which “/AAA/A.txt” is registered as the storage destination (T1021) and [File A] is registered as the file ID (T1022). Here, “/AAA/A.txt” shown in FIG. 5 includes “/ AAA /” as a directory portion and “A.txt” as a file name portion. [File A] shown in FIG. 5 indicates a hash value generated from the data block of the file specified by the storage destination “/AAA/A.txt”, and uses the hash function of SHA-256. If it is, the hash value is 256 bits long.

  Next, the CPU 101 of the terminal device 100 transmits a registration request signal for requesting registration of a newly registered file to the file storage device 200 using the communication unit 105 (S104).

  FIG. 6 shows an example of the data structure of the registration request signal. The registration request signal illustrated in FIG. 6 includes an environment ID (T1031), a file ID (T1032), a file name (T1033), and a data block (T1034).

  The environment ID (T1031) illustrated in FIG. 6 is identification information for identifying environment management information in the file storage device 200. For example, as the environment ID (T1031), information for identifying the terminal device 100, information for identifying a user who uses the terminal device 100, and the like can be used. As information for identifying the terminal device 100, a manufacturing number of the terminal device 100, an IP address set in the terminal device 100, a MAC address preset in the communication unit 105 of the terminal device 100, or the like can be used. . As information for identifying a user who uses the terminal device 100, a login ID requested to be input when starting operation of the terminal device 100, owner information set in advance in the terminal device 100, or the like is used. it can. Note that the environment management information is identified as long as the specific environment management information can be distinguished from other environment management information, and the data string of the environment ID assigned to the specific environment management information is not necessarily grasped specifically. do not have to. For example, information that identifies the terminal device 100 and information that identifies a user who uses the terminal device 100 is shared between the terminal device 100 and the file storage device 200 as an encryption key for encryption processing and a decryption key for decryption processing. In addition, encrypted data obtained by encrypting a predetermined data string shared between the terminal device 100 and the file storage device 200 in the terminal device 100 may be used as the environment ID. In this case, the file storage device 200 registers the encrypted data encrypted in the terminal device 100 in advance as an encryption key that can decrypt a predetermined data string shared between the terminal device 100 and the file storage device 200. The environment management information can be identified by specifying the information for identifying the terminal device 100 that is present and the information for identifying the user who uses the terminal device 100. Note that the above points are not applied only to the environment ID (T1031), and the same applies to other identification information.

  The file ID (T1032) illustrated in FIG. 6 is identification information generated in step S102. For example, when generated using the hash function of SHA-256, the hash value is 256 bits long.

  The file name (T1033) illustrated in FIG. 6 indicates the file name of the file detected in step S101. For example, “A.txt” in the storage location (T1021) shown in FIG.

  A data block (T1034) illustrated in FIG. 6 indicates a data block that is a main body portion of the file detected in step S101. In the example shown in FIG. 5, the file specified by the storage location (T1021) “/AAA/A.txt” has an extension “.txt” and indicates that it is a text file. In this case, the text data stored in the data block of the text file is stored in the data block (T1034) shown in FIG. In step S104, each item of the registration request signal shown in FIG. 6 may be transmitted in a batch, or may be divided into a plurality of transmission signals and transmitted. In addition, when transmitting by dividing into a plurality of transmission signals, the items of the registration request signal shown in FIG. 6 may be transmitted in duplicate. For example, in the first transmission process, the environment ID (T1031), the file ID (T1032), and the file name (T1033) are transmitted, and in the second transmission process, the file ID (T1032) and the data block (T1034) are transmitted. You may send it. The above point is not applied only to the transmission / reception process of the registration request signal T103, and the same applies to the transmission / reception processes of other request signals.

  Next, the CPU 201 of the file storage device 200 receives the registration request signal transmitted from the terminal device 100 using the communication unit 203 (S201).

  The CPU 201 determines whether or not the file management information T201 having the file ID (T2011) corresponding to the file ID (1032) is registered, using the file ID (T1032) of the registration request signal T103 received in step S201. (S202). In step S202, the CPU 201 determines that the file management information T201 having the file ID (T2011) corresponding to the file ID (1032) is not registered (YES in S202), and executes the steps after step S203. . On the other hand, in step S202, the CPU 201 determines that the file management information T201 having the file ID (T2011) corresponding to the file ID (1032) is already registered (NO in S202), and executes the step S205. To do. Note that even if the identification information generated in the above step S102 is identification information generated between different environments, the hash function used when generating the identification information is the same, so the contents of the data block portion of the file Are the same, the obtained hash value is also the same value.

  In step S203, the CPU 201 stores a file having the contents shown in the data block (T1034) of the registration request signal T103 received in step S201 in the storage unit 202 (S203).

  The CPU 201 updates the file management information T201 and the environment management information T202 based on the registration request signal received in step S201 (S204, S205).

  In step S204, the CPU 201 registers the file ID (T2011) of the file management information T201 using the file ID (T1032) of the registration request signal T103 received in step S201.

  In step S205, the CPU 201 registers the storage location (T2012) of the file management information T201 using the storage location (including the file name) of the file stored in step S203.

  The content example of the file management information T201 shown in FIG. 10 indicates that the file specified by [File A] of the file ID (T2011) is stored in “/ data / 1111” shown in the storage destination (T2012). Show.

  In step S204, the CPU 201 registers the environment ID (T2021) of the environment management information T202 using the environment ID (T1031) of the registration request signal T103 received in step S201.

  In step S204, the CPU 201 registers the file ID (T2022) of the environment management information T202 using the file ID (T1032) of the registration request signal T103 received in step S201.

  In step S204, the CPU 201 registers the file name (T2023) of the environment management information T202 using the file name (T1033) of the registration request signal T103 received in step S201.

  At the time of step S204, the deletion date (T2024) of the environment management information T202 is not registered.

The content example of the environment management information T202 shown in FIG. 11 includes [Environment 1] as the environment ID (T2021), [File A] as the file ID (T2022), “A.txt” as the file name (T2023), The environmental management information T202 having “-” as the deletion date (T2024) is shown. Here, [Environment 1] indicates a data string having a predetermined number of digits, and information for identifying the terminal device 100, information for identifying a user who uses the terminal device 100, and the like can be used. Here, [File A] indicates a hash value of a predetermined length, as in FIG. Here, “-” shown as the deletion date / time (T2024) indicates that the deletion date / time (T2024) is not substantially set.
[5. Process flow during file operation]
FIG. 16 shows an example of the flow of processing during file operations. First, the CPU 101 of the terminal device 100 monitors an operation on a file stored in the protection area T1033 configured in the storage unit 102, such as a reference request or a deletion request for the file stored in the protection area T1033. An operation is detected (S301).

  When the CPU 101 detects an operation for the file stored in the protection area T1033 in step S301, the CPU 101 identifies the operation type of the detected operation (S302).

  The CPU 101 executes an update process for the operation history information T101 (S303). In step S303, the CPU 101 specifies the file to be operated detected in step S301, and registers the file ID (T1011) of the operation history information T101 using information for identifying the specified file. Here, the information for identifying the specified file can be acquired by generating a hash value of a predetermined number of digits from the data block of the specified file using the same procedure as in S102 described above. Further, the file ID (T1022) corresponding to the storage location (T1021) corresponding to the specified file storage location (including the file name) may be acquired from the protection area management information T102.

  In step S303, the CPU 101 registers the operation type (T1012) of the operation history information T101 using the operation type specified in step S302. In step S303, the CPU 101 registers the operation date / time (T1022) of the operation history information T101 using the current date / time information indicated by the system clock included in the terminal device 100.

  The content example of the operation history information T101 shown in FIG. 4 includes “File A” as the file ID (T1011), “Register” as the operation type (T1012), and “2009/02/02, 15 as the operation date and time (T1013). 0:00 ". In this example, the file specified by [File A] indicated by the file ID (T1011) is registered in the protection area T1033 at “2009/02/02, 15:00”.

  The content example of the operation history information T101 illustrated in FIG. 4 includes “file A” as the file ID (T1011), “reference” as the operation type (T1012), and “2009/02/02, 15 as the operation date / time (T1013)”. : 10 ”. In this example, the file specified by [File A] indicated by the file ID (T1011) is stored in the protection area T1033 at “2009/02/02, 15:10”, and the file is opened. Indicates that it was referenced by the operation.

  The content example of the operation history information T101 illustrated in FIG. 4 includes “file A” as the file ID (T1011), “reference” as the operation type (T1012), and “2009/02 / 09,10” as the operation date / time (T1013). 0:00 ". In this example, the file specified by [File A] indicated by the file ID (T1011) is stored in the protection area T1033 at “2009/02/09, 10:00”, and the file is opened. Indicates that it was referenced by the operation.

  The content example of the operation history information T101 shown in FIG. 4 includes “File A” as the file ID (T1011), “Delete” as the operation type (T1012), and “2009/02 / 09,10” as the operation date / time (T1013). : 10 ”. In this example, the file specified by [File A] indicated by the file ID (T1011) is deleted from the protection area T1033 at “2009/02/09, 10:10”.

  The CPU 101 determines whether or not the operation type identified in step S302 indicates file deletion (S304), and when it is determined that the operation type indicates deletion (YES in S304), executes the processing after step S305. To do. On the other hand, if the CPU 101 determines that the operation type indicates other than deletion (NO in S304), the CPU 101 does not execute the processes in and after step S305. Here, the operation type indicating deletion means an operation type indicating an operation of deleting a file from the protection area T1033. For example, an operation for inputting a deletion command for designating a file stored in the protection area T1033 and instructing execution of deletion processing, or a file stored in the protection area T1033 in another area (for example, the general area T1034) The operation to be moved is an operation whose operation type indicates deletion.

  In step S305, the CPU 101 identifies the operation target file detected in step S301, and determines the importance of the identified file based on the operation history information T101 related to the identified file (S305).

  Specifically, the CPU 101 first specifies the operation target file detected in step S301, and acquires operation history information T101 having a file ID (T1011) corresponding to information for identifying the specified file.

  The CPU 101 indicates the time that the specified file has existed from the operation date / time (T1013) of the operation history information T101 whose operation type (T1012) indicates “registration” in the acquired operation history information T101. Calculate the file lifetime. In the file lifetime calculation process, the end of the file lifetime may be the current date and time at the time of calculation indicated by the system clock of the terminal device 100, or an operation history indicating “delete” as the operation type (T1012). The date and time indicated in the information operation date and time (T1013) may be used. The file lifetime may be in seconds, minutes, hours, days, months, years, or these. May be expressed in any combination.

  The CPU 101 specifies the operation date / time (T1013) of the operation history information T101 in which the operation type (T1012) indicates “reference” in the acquired operation history information T101 as a starting point. The last access elapsed time indicating the elapsed time since the last time the file was referenced is calculated. In the process of calculating the last access elapsed time, the end of the last access elapsed time may be the current date and time at the time of calculation indicated by the system clock of the terminal device 100, or “delete” is selected as the operation type (T1012). The date and time indicated by the operation date and time (T1013) of the operation history information shown may be used. The last access elapsed time may be a second unit, a minute unit, an hour unit, a day unit, a month unit, a year unit, Any combination of these may be used.

  For example, the CPU 101 calculates the importance A of the identified file by calculating the following equation. However, the following formula is an example in the present embodiment, and is not necessarily limited to this.

  In the above formula, the importance A indicates a larger value as the file lifetime becomes a larger value. That is, it is judged that the importance of a file is so high that a file lifetime becomes a large value. On the other hand, the smaller the value of the file lifetime, the less important the file is. This determination criterion is effective in the case where the longer the time stored in the protection area T1033 is, the higher the importance of the file is. The present embodiment is not necessarily limited to the above criteria.

  In the above formula, the importance A indicates a larger value as the last access elapsed time becomes smaller. That is, it is determined that the importance of the file is higher as the last access elapsed time becomes smaller. On the other hand, it is determined that the importance of the file is lower as the access elapsed time becomes larger. This determination criterion is effective when the tendency that the importance of the file is higher as the elapsed time from the last operation in the state stored in the protection area T1033 is shorter. The present embodiment is not necessarily limited to the above criteria.

  In addition, as described above, by judging the judgment criteria using the file lifetime and the judgment criteria using the last access elapsed time, the relative relationship between the file lifetime and the last access elapsed time is obtained. Based on this, the importance A can be determined. In other words, in the above formula, the greater the value of the file lifetime is with respect to the last access elapsed time, the greater the importance A, and it is determined that the importance of the file is higher. On the other hand, as the file lifetime becomes smaller than the last access elapsed time, the importance A indicates a smaller value, and the importance of the file is determined to be lower.

  When the degree of importance is determined based on the relative relationship between the file lifetime and the last access elapsed time, even if the file stored in the protection area T1033 is a long time, the unreferenced period is long. It can be judged that the importance of the file is low. Further, even if a file stored in the protection area T1033 has a short time, if the file is frequently referenced, it can be determined that the importance of the file is high.

  However, in this embodiment, the CPU 101 may calculate the importance A based on either the file lifetime or the last access elapsed time.

  Next, the CPU 101 determines an erasure date and time indicating the date and time when the file registered in the file storage device 200 is erased based on the importance A determined in step S305 (S306). The erasure date may be in seconds, minutes, hours, hours, days, months, years, or these. Any combination may be used.

  For example, the CPU 101 determines the erase date and time by calculating the following equation. However, the following formula is an example in the present embodiment, and is not necessarily limited to this.

(T)
In the above formula, the unit time is a value that can be set as appropriate according to the operation. In the above formula, the setting unit of the unit time is not necessarily limited, and may be set in seconds, set in hours, set in days, or any of these. It may be expressed in combination.

  In the above formula, the current date and time is a value indicating the current date and time at the time of calculation indicated by the system clock of the terminal device 100. Note that the CPU 101 executes unit conversion when adding the current date and time to the value obtained by multiplying the unit time and the importance level described above. In the above formula, a guarantee period indicating a minimum period for guaranteeing that the file stored in the file storage device 200 can be taken out may be added to the current date and time.

  Next, the CPU 101 specifies the file that is the target of the operation that is determined to be deleted in the operation type in step S304, and sends a deletion request signal T104 that requests deletion of the specified file to the communication unit 105. The file is transmitted to the file storage device 200 (S307).

  FIG. 7 shows an example of the data structure of the deletion request signal T104. The deletion request signal T104 illustrated in FIG. 7 includes an environment ID (T1041), a file ID (T1042), and a deletion date / time (T1043).

  The environment ID (T1041) shown in FIG. 7 is identification information for identifying the environment management information in the file storage device 200, similarly to the environment ID (T1031) of the registration request signal T103 shown in FIG. For example, as the environment ID (T1031), information for identifying the terminal device 100, information for identifying a user who uses the terminal device 100, and the like can be used. As information for identifying the terminal device 100, a manufacturing number of the terminal device 100, an IP address set in the terminal device 100, a MAC address preset in the communication unit 105 of the terminal device 100, or the like can be used. . As information for identifying a user who uses the terminal device 100, a login ID requested to be input when starting operation of the terminal device 100, owner information set in advance in the terminal device 100, or the like is used. it can. Note that the environment management information is identified as long as the specific environment management information can be distinguished from other environment management information, and the data string of the environment ID assigned to the specific environment management information is not necessarily grasped specifically. do not have to. For example, information that identifies the terminal device 100 and information that identifies a user who uses the terminal device 100 is shared between the terminal device 100 and the file storage device 200 as an encryption key for encryption processing and a decryption key for decryption processing. In addition, encrypted data obtained by encrypting a predetermined data string shared between the terminal device 100 and the file storage device 200 in the terminal device 100 may be used as the environment ID. In this case, the file storage device 200 registers the encrypted data encrypted in the terminal device 100 in advance as an encryption key that can decrypt a predetermined data string shared between the terminal device 100 and the file storage device 200. The environment management information can be identified by specifying the information for identifying the terminal device 100 that is present and the information for identifying the user who uses the terminal device 100. Note that the above points are not applied only to the environment ID (T1031), and the same applies to other identification information.

  The file ID (T1042) shown in FIG. 7 is identification information for identifying the file that is the target of the deletion request. For example, when it is generated using the hash function of SHA-256, it becomes a 256-bit hash value. The CPU 101 can acquire the file ID (T1022) by referring to the protection area management information T102 based on the storage destination of the file to be deleted. Similarly to step S102, the CPU 101 can set a hash value obtained from a data block of a file to be deleted using a hash function such as SHA-256 as a file ID (T1022).

  The deletion date / time (T1043) shown in FIG. 7 indicates the deletion date / time acquired in step S306. The deletion date and time (T1043) may be in seconds, minutes, hours, days, months, or years. These may be expressed in any combination.

  Next, the CPU 201 of the file storage device 200 receives the deletion request signal T104 transmitted from the terminal device 100 using the communication unit 203 (S401).

  The CPU 201 updates the environment management information T202 based on the deletion request signal T104 received in step S401 (S402).

  In step S402, the CPU 201 corresponds to the environment ID (T2021) corresponding to the environment ID (T1041) of the deletion request signal T104 received in step S401 and the file ID (T1042) of the deletion request signal T104 received in step S401. The environment management information T202 having the file ID (T2022) is specified.

  In step S402, the CPU 201 updates the deletion date / time (T2024) of the specified environment management information T202 using the deletion date / time (T1043) of the deletion request signal T104 received in step S401.

The content example of the environment management information T202 shown in FIG. 11 includes “environment 2” as the environment ID (T2021), “file A” as the file ID (T2022), “A123.txt” as the file name (T2023), It has “2009/3/1, 15:00” as the deletion date and time (T2024). In this example, the request signal (T103, T104, T105) in which the file specified by [File A] indicated by the file ID (T2022) has an environment ID corresponding to [Environment 2] indicated by the environment ID (T2021). , T106), the terminal device 100 has “A123.txt” shown in the file name (T2023). In this example, the terminal device 100 that transmits a request signal (T103, T104, T105, T106) having an environment ID corresponding to [Environment 2] indicated by the environment ID (T2021) is indicated by the file ID (T2022). This indicates that the deletion date and time is determined to be “2009/3/1, 15:00” for the file specified by [File A].
[6. Flow of processing during reference request operation]
FIG. 17 shows an example of the flow of processing during a reference request operation. First, the CPU 101 of the terminal device 100 detects that a reference request operation for requesting reference to a file registered in the file storage device 200 has been performed based on a signal acquired from the operation unit 104 via an internal communication line. (S501).

  When the CPU 101 detects that a reference request operation has been performed in step S501, the CPU 101 transmits a reference request signal T105 to the file storage device 200 using the communication unit 105 (S502).

  FIG. 8 shows an example of the data structure of the reference request signal T105. The reference request signal T105 shown in FIG. 8 has an environment ID (T1051). The environment ID (T1051) shown in FIG. 8 is identification information for identifying the environment management information in the file storage device 200, similarly to the environment ID (T1031) of the registration request signal T103 shown in FIG. For example, as the environment ID (T1031), information for identifying the terminal device 100, information for identifying a user who uses the terminal device 100, and the like can be used.

  Next, the CPU 201 of the file storage device 200 receives the reference request signal T105 transmitted from the terminal device 100 using the communication unit 203 (S601).

  The CPU 201 specifies the environment management information T202 having the environment ID (T2021) corresponding to the environment ID (T1051) of the reference request signal T105 received in step S601, and shows a list of files based on the specified environment management information T202. The backup list information T203 is generated (S602).

  In step S602, the CPU 201 uses the file ID (T2022) of the environment management information T202 specified using the environment ID (T1051) of the reference request signal T105 received in step S601, and the file ID (T2022) of the backup list information T203. T2031) is set.

  In step S602, the CPU 201 uses the file name (T2023) of the environment management information T202 specified using the environment ID (T1051) of the reference request signal T105 received in step S601, and the file name (T2023) of the backup list information T203. T2032) is set.

  In step S602, when there are a plurality of pieces of environment management information T202 specified using the environment ID (T1051) of the reference request signal T105 received in step S601, the CPU 201 has file IDs corresponding to the specified number ( T2031) and backup list information having a file name (T2032) are generated.

  The CPU 201 transmits the backup list information T203 generated in step S602 to the terminal device 100 using the communication unit 203 (S603). In step S603, each item of the backup list information shown in FIG. 12 may be transmitted in a batch, or may be divided into a plurality of transmission signals and transmitted.

  Next, the CPU 101 of the terminal device 100 receives the backup list information T203 transmitted from the file storage device 200 using the communication unit 105 (S503).

  The CPU 101 displays the list of files indicated in the backup list information T203 received in step S503 on the display device using the display unit 103 (S504). FIG. 19 shows an example of the contents of the file list screen displayed in step S504. The content example of the file list screen shown in FIG. 19 includes a selection field D101 for accepting a selection operation for a file to be downloaded, a file name display field D102 for displaying a file name, and an operation for instructing execution of downloading of the selected file. Download execution button D103.

  The CPU 101 detects the selection of the file by obtaining a signal indicating that the selection operation of the file to be downloaded in the selection field D101 has been received from the operation unit 104 via the internal communication line (S505).

  The CPU 101 obtains a signal indicating that the download execution button D103 has been pressed through the internal communication line from the operation unit 104, thereby detecting that an instruction to execute download has been issued (S505).

  When the CPU 101 detects that the execution of the download is instructed, the CPU 101 transmits a download request signal T106 for requesting the download of the selection target file detected in step S505 to the file storage device 200 using the communication unit 105 ( S506).

  FIG. 9 shows an example of the data structure of the download request signal T106. The download request signal T106 shown in FIG. 9 has an environment ID (T1061) and a file ID (T1062).

  The environment ID (T1061) shown in FIG. 9 is identification information for identifying environment management information in the file storage device 200, similarly to the environment ID (T1031) of the registration request signal T103 shown in FIG. For example, as the environment ID (T1031), information for identifying the terminal device 100, information for identifying a user who uses the terminal device 100, and the like can be used.

  A file ID (T1062) illustrated in FIG. 9 indicates a file ID corresponding to the file to be selected detected in step S505. The CPU 101 can acquire the file ID corresponding to the file name of the file to be selected detected in step S505 by referring to the file ID (T2031) of the backup list information T203 received in step S503.

  Next, the CPU 201 of the file storage device 200 receives the download request signal T106 transmitted from the terminal device 100 using the communication unit 203 (S604).

  When the CPU 201 receives the download request signal T106 in step S604, the CPU 201 transmits download file information indicating information related to the file specified based on the received download request signal T106 to the terminal device 100 using the communication unit 203 ( S605).

  FIG. 13 shows an example of the data structure of the download file information T204. The download file information T204 illustrated in FIG. 13 includes a file ID (T2041), a file name (T2042), and a data block (T2043).

  In step S605, the CPU 201 sets the file ID (T2041) of the download file information T204 using the file ID (T1062) of the download request signal T106 received in step S604.

  In step S605, the CPU 201 corresponds to the environment ID (T2021) corresponding to the environment ID (T1061) of the download request signal T106 received in step S604 and the file ID (T1062) of the download request signal T106 received in step S604. The environment management information T202 having the file ID (T2022) is specified.

  In step S605, the CPU 201 sets the file name (T2042) of the download file information T204 using the file name (T2023) of the specified environment management information T202.

  In step S605, the CPU 201 specifies file management information T201 having a file ID (T2011) corresponding to the file ID (T1062) of the download request signal T106 received in step S604.

  In step S605, the CPU 201 sets the data block (T2043) of the download file information T204 using the data block of the storage destination file indicated by the storage destination (T2012) of the specified file management information T201.

  Next, the CPU 101 of the terminal device 100 receives the download file information T204 transmitted from the file storage device 200 using the communication unit 105 (S507).

  In step S507, the CPU 101 stores a file having a file name indicated by the file name (T2041) of the received download file information T204 and having a data block indicated by the data block (T2043) of the received download file information T204. Store in the storage unit 102.

Through the above steps, the terminal device 100 downloads the file stored in the storage unit 202 of the file storage device 200 even when the file is deleted from the protected area T1033 configured in the storage unit 102. The file deleted from the protected area T1033 can be restored.
[7. Flow of condition monitoring process executed in file storage device]
Next, a flow of condition monitoring processing executed in the file storage device 200 will be described. FIG. 18 shows an example of the flow of condition monitoring processing executed in the file device 200.

  First, the CPU 201 of the file storage device 200 refers to the system date and time indicating the current date and time indicated by the system clock of the file storage device 200 (S701), and refers to the deletion date and time (T2024) of the environment management information T202 in step S701. The system date and time are compared (S702).

  In step S702, the CPU 201 specifies environment management information T202 having a deletion date (T2024) indicating a time point in the past from the system date and time referred to in step S701.

  If there is one or more specified environment management information T202, the CPU 201 determines that there is environment management information T202 for which the deletion date / time has arrived (YES in S703), and executes the processes after step S704. On the other hand, if the environmental management information T202 identified in step S702 is zero, that is, if one environmental management information T202 cannot be identified, the CPU 201 has the environmental management information T202 that has been deleted. It is determined not to be performed (NO in S703), and the processes after step S704 are not executed.

  In step S704, the CPU 201 searches for other environment management information T202 having the same file ID (T2022) as the file ID (T2022) of the environment management information T202 specified in step S702 (S704). That is, in step S704, the CPU 201 manages the environment management information T202 having the same file ID (T2022) as the file ID (T2022) of the environment management information T202 specified in step S702, and the deletion date has not arrived. Information T202 is specified.

  When the environment management information T202 identified by the search in step S704 is zero (YES in step S705), the CPU 201 executes step S706, step S707, and step S708. On the other hand, when the environment management information T202 specified by the search in step S704 is not zero (NO in step S705), the CPU 201 executes step S708 without executing steps S706 and S707.

  In step S706, the CPU 201 specifies file management information T201 having a file ID (T2011) corresponding to the file ID (T2022) of the environment management information T202 specified in step S702.

  In step S706, the CPU 201 deletes the storage destination file indicated by the storage destination (T2012) of the file management information T201 specified in step S706.

  In step S707, the CPU 201 deletes the file management information T201 specified in step S706.

  In step S708, the CPU 201 deletes the environment management information T202 specified in step S702.

  Even if there are a plurality of pieces of environment management information T202 in which the same value is set in the file ID (T2022), the values set in the deletion date and time (T2024) of the respective environment management information T202 are obtained. Accordingly, it is determined whether or not a deletion date and time unique to each environment management information T202 has arrived. Then, by appropriately deleting the environment management information T202 that has been determined that the deletion date / time has arrived, the environment management information T202 that has not reached the deletion date / time can be managed.

  The case where there are a plurality of pieces of environment management information T202 in which the same value is set in the file ID (T2022) means that a file associated with the file ID having the same value is shared between different environments. That is, there is environment management information T202 having the same file ID (T2022) as the file ID (T2022) of environment management information T202 identified in step S702, and there is environment management information T202 that has not been deleted. Means that there is an environment in which the file associated with the file ID (T2022) continues to be used. Therefore, when the search result is not 0 in step S705 (NO in S705), the process S706 and the step S707 are not executed, so that the file for the environment using the environment management information T202 whose deletion date / time has not arrived. Can continue to be provided. Therefore, in the file storage device 100, by sharing a file having the same file content between environments, the storage capacity of the file storage device 200 can be effectively utilized.

[1. Regarding the configuration of the program according to the second embodiment]
FIG. 20 illustrates a configuration example of a program executed in the terminal device 100 according to the second embodiment. In the configuration example of the program shown in FIG. 20, the same reference numerals are assigned to the same configurations as the configuration example of the program shown in FIG. The configuration example of the program illustrated in FIG. 20 is different from the configuration of the program illustrated in FIG. 2 in that, for example, the update request execution unit PG113 is included. Therefore, for simplification of description, description of components having the same contents is partially omitted.

  When the operation content detected by the process of the file operation detection unit PG109 indicates a change in the file content, the update request execution unit PG113 illustrated in FIG. 20 uses the communication unit 105 to transmit information regarding the detected change to the file storage device 200. The CPU 101 is operated as a component that executes predetermined processing such as transmission.

  FIG. 21 illustrates a configuration example of a program executed in the file storage device 200 according to the second embodiment. In the configuration example of the program shown in FIG. 21, the same reference numerals are assigned to the same configurations as the configuration example of the program shown in FIG. The configuration example of the program illustrated in FIG. 21 is different from the configuration of the program illustrated in FIG. 3 in that, for example, the update request reception unit PG211 is included. Therefore, for simplification of description, description of components having the same contents is partially omitted.

The update request receiving unit PG211 illustrated in FIG. 21 receives information related to the change transmitted by the process of the update request execution unit PG113, and operates the CPU 201 as a component that executes predetermined processing based on the received content.
[2. Regarding the flow of processing during file operations according to the second embodiment]
24 and 25 show an example of the flow of processing during file operation according to the second embodiment. The process flow at the time of file operation shown in FIGS. 24 and 25 is given the same reference numeral to the same configuration as the process flow example shown in FIG. 16 in the first embodiment. The example of the processing flow at the time of file operation shown in FIGS. 24 and 25 includes, for example, steps S309 to S311 and steps S403 to S406, and the processing at the time of file operation according to the first embodiment shown in FIG. This is different from the flow example. The first half of the example of the process flow during the file operation according to the second embodiment shown in FIGS. 24 and 25 is the same as the process flow example during the file operation according to the first embodiment shown in FIG. Since it is a procedure, description thereof is partially omitted.

  First, the CPU 101 of the terminal device 100 monitors an operation on a file stored in the protection area T1033 configured in the storage unit 102, and detects an operation on the file stored in the protection area T1033 (S301). .

  When the CPU 101 detects an operation on the file stored in the protection area T1033 in step S301, the CPU 101 identifies the operation type of the detected operation (S302), and executes an update process of the operation history information T101 (S303).

  The CPU 101 determines whether or not the operation type specified in step S302 indicates file deletion (S304), and determines that the operation type indicates other than deletion (NO in S304), the operation type specified in step S302. Determines whether or not indicates a file change (S308).

  If the CPU 101 determines that the operation type identified in step S302 indicates a file change (YES in step S308), the CPU 101 executes the processing from step S309. On the other hand, if the CPU 101 determines that the operation type indicates other than a file change (NO in S308), the CPU 101 does not execute the processes after step S309.

  In step S309, the CPU 101 identifies the operation target file detected in step S301, and generates identification information for the identified file using the same procedure as in step S102 described above (S309).

  The CPU 101 of the terminal device 100 acquires the file ID (T1022) corresponding to the storage location (T1021) corresponding to the storage location (including the file name) of the operation target file detected in step S301 from the protection area management information T102. Then, the acquired file ID is handled as a related ID (S310).

  The CPU 101 updates the file ID (T1022) corresponding to the storage location (T1021) corresponding to the storage location (including the file name) of the operation target file detected in step S301, using the related ID acquired in step S310. (S311).

  The CPU 101 updates the operation history information T101 (S312). In step S303, when the CPU 101 updates the operation history information T101 using the identification information acquired by generating a hash value having a predetermined number of digits from the data block of the file detected in step S301, the CPU 101 The operation history information has been updated. Therefore, in step S312, the CPU 101 updates the operation history information related to the file before the change by registering the operation history information using the related ID acquired in step S310. In this case, the CPU 101 may omit step S312.

  On the other hand, in step S303, the CPU 101 updates the operation history information T101 using the file ID (T1022) corresponding to the storage location (T1021) corresponding to the storage location (including the file name) of the file detected in step S301. In this case, the operation history information T101 for the file before change is updated. Therefore, in step S312, the CPU 101 registers the operation history information T101 by using the identification information acquired by generating a hash value of a predetermined number of digits from the data block of the file detected in step S301, so that the changed history is obtained. Updates the operation history information related to the file.

  The CPU 101 transmits an update request signal T107 for requesting update of the file detected in step S301 to the file storage device 200 using the communication unit 105 (S313).

  FIG. 22 shows an example of the data structure of the update request signal T107. The update request signal T107 illustrated in FIG. 22 includes an environment ID (T1071), a file ID (T1072), a file name (T1073), a data block (T1074), and a related ID (T1075).

  The related ID (T1071), file ID (T1072), file name (T1073), and data block (T1074) shown in FIG. 22 are the same as those in FIG.

  The related ID (T1075) illustrated in FIG. 22 indicates the related ID acquired in step S310.

  Next, the CPU 201 of the file storage device 200 receives the update request signal T107 transmitted from the terminal device 100 using the communication unit 203 (T403).

  The CPU 201 determines whether or not the file management information T201 having the file ID (T2011) corresponding to the file ID (1072) is registered, using the file ID (T1072) of the update request signal T107 received in step S403. (S404). In step S404, the CPU 201 determines that the file management information T201 having the file ID (T2011) corresponding to the file ID (1072) is not registered (YES in step S404), and executes step S405 and subsequent steps. . On the other hand, in step S404, the CPU 201 determines that the file management information T201 having the file ID (T2011) corresponding to the file ID (1072) is already registered (NO in S404), and executes the step S407. To do.

  The CPU 201 stores a file having the contents indicated in the data block (T1074) of the update request signal T107 received in step S403 in the storage unit 202 (405).

  The CPU 201 updates the file management information T201 and the environment management information T202 based on the update request signal received in step S403 (S406, S407).

  In step S406, the CPU 201 registers the file ID (T2011) of the file management information T201 using the file ID (T1032) of the update request signal T107 received in step S403.

  In step S406, the CPU 201 registers the storage location (T2012) of the file management information T201 using the storage location (including the file name) of the file stored in step S405.

  In step S406, the CPU 201 registers the related ID (T2013) of the file management information T201 using the related ID (T1075) of the update request signal T107 received in step S403.

  The content example of the file management information T201 shown in FIG. 23 indicates that the file specified by [file A1] of the file ID (T2011) is stored in “/ data / 1111” shown in the storage destination (T2012). Show. In this example, “-” is shown in the related ID (T2013), indicating that substantially nothing is set as the related ID.

  In the content example of the file management information T201 shown in FIG. 23, the file specified by [file A2] of the file ID (T2011) is stored in “/ data / 1112” shown in the storage destination (T2012). This indicates that [file A1] is registered as the ID (T2013).

  In step S407, the CPU 201 registers the environment ID (T2021) of the environment management information T202 using the environment ID (T1071) of the update request signal T107 received in step S403.

  In step S407, the CPU 201 registers the file ID (T2022) of the environment management information T202 using the file ID (T1072) of the update request signal T107 received in step S403.

  In step S407, the CPU 201 registers the file name (T2023) of the environment management information T202 using the file name (T1073) of the update request signal T107 received in step S403.

  In response to receiving the update request in step S <b> 403, the CPU 201 transmits a signal indicating that the update request has been accepted to the terminal device 100 using the communication unit 203 at an arbitrary timing.

  Next, the CPU 101 of the terminal device 100 receives a signal indicating that the update request transmitted from the file storage device 200 has been received using the communication unit 105, and executes step S314 and the subsequent steps. As a result, the terminal device 100 sets a timing for deleting the file before change stored in the file storage device 200 from the storage unit 202 of the file storage device 200.

  Based on the operation history information T101 related to the file specified by the related ID acquired in step S310, the CPU 101 determines the importance of the file specified by the related ID using the same procedure as in step S305 described above ( S314).

  Based on the importance determined in step S314, the CPU 101 determines an erasure date and time indicating the date and time when the file registered in the file storage device 200 is erased using the same procedure as in step S306 described above (S315). . The erasure date may be in seconds, minutes, hours, hours, days, months, years, or these. Any combination may be used.

  The CPU 101 transmits a deletion request signal T104 requesting deletion of the file specified by the related ID acquired in step S310 to the file storage device 200 using the communication unit 105 (S316). The deletion request signal T104 is the same as the deletion request signal T104 shown in FIG.

  Next, the CPU 201 of the file storage device 200 receives the deletion request signal T104 transmitted from the terminal device 100 using the communication unit 203 (S407).

  Based on the deletion request signal T104 received in step S401, the CPU 201 updates the environment management information T202 using the same procedure as in step S402 described above (S408).

  Thereby, even when a change operation is performed on the contents of a file in the terminal device 100, the changed file can be backed up in the file storage device 200.

In addition, since it is possible to set the timing of deletion of the file before change stored in the file storage device 200 in conjunction with the change of the file, it is advantageous that the file before change stays in the file storage device 200. Therefore, the storage capacity of the file storage device 200 can be used effectively.
[3. Regarding the flow of condition monitoring processing according to the second embodiment]
FIG. 26 illustrates an example of a flow of condition monitoring processing according to the second embodiment. In the flow of the condition monitoring process shown in FIG. 26, the same reference numerals are assigned to the same components as the flow of the process shown in FIG. The condition monitoring process flow illustrated in FIG. 26 differs from the condition monitoring process flow according to the first embodiment illustrated in FIG. 18 in that, for example, the process includes a step S709 and a step S710. The first half of the flow of the condition monitoring process according to the second embodiment shown in FIG. 26 is the same processing procedure as the flow of the condition monitoring process according to the first embodiment shown in FIG. .

  First, the CPU 201 of the file storage device 200 refers to the system date and time of the file storage device 200 (S701), and compares the deletion date and time (T2024) of the environment management information T202 with the system date and time referred to in step S701 (S702). In step S702, the CPU 201 specifies environment management information T202 having a deletion date (T2024) indicating a time point in the past from the system date and time referred to in step S701.

  As a result of the comparison in step S702, when the CPU 201 determines that there is environment management information T202 for which the deletion date / time has arrived (YES in S703), the CPU 201 executes the processing after step S704. On the other hand, as a result of the comparison in step S702, the CPU 201 determines that there is no environment management information T202 for which the deletion date / time has arrived (NO in step S703), and does not execute the processing after step S704.

  In step S704, the CPU 201 searches for other environment management information T202 having the same file ID (T2022) as the file ID (T2022) of the environment management information T202 specified in step S702 (S704). That is, in step S704, the CPU 201 manages the environment management information T202 having the same file ID (T2022) as the file ID (T2022) of the environment management information T202 specified in step S702, and the deletion date has not arrived. Information T202 is specified.

  CPU201 performs process S706 thru | or process S710, when the environment management information T202 specified by the search in process S704 is 0 cases (it is YES at S705). On the other hand, when the environment management information T202 specified by the search in step S704 is not zero (NO in S705), the CPU 201 executes step S711.

  In step S710, the CPU 201 specifies file management information T201 having a file ID (T2011) corresponding to the file ID (T2022) of the environment management information T202 specified in step S702.

  In step S710, the CPU 201 acquires a related ID by referring to the related ID (T2013) of the file management information T201 specified in step S710.

  In step S706, the CPU 201 specifies file management information T201 having a file ID (T2011) corresponding to the file ID (T2022) of the environment management information T202 specified in step S702.

  In step S706, the CPU 201 deletes the storage destination file indicated by the storage destination (T2012) of the file management information T201 specified in step S706.

  In step S707, the CPU 201 deletes the file management information T201 specified in step S706.

  In step S708, the CPU 201 deletes the environment management information T202 specified in step S702.

  In step S709, the CPU 201 determines whether or not a related file exists. For example, if a value other than the initial value is set in the related ID (T2013) referred to in step S710, the CPU 201 can determine that a related file exists (YES in S709). Further, the CPU 201 searches the file management information T2011 having the file ID (T2011) corresponding to the related ID acquired in step S710, and determines that the related file exists when the corresponding file management information T2011 exists. Yes (YES in S709).

  In step S709, if the CPU 101 determines that a related file exists (YES in step S709), the CPU 101 executes step S704 and subsequent steps using the related ID. That is, a search process for other environment information having the same file ID as the related ID acquired in step S710 is executed, and step S705 is executed based on the search result. After that, since it is the same as the above-mentioned description, description is abbreviate | omitted.

  On the other hand, if the CPU 101 determines in step S709 that the related file does not exist (NO in step S709), the CPU 101 ends the condition monitoring process according to the second embodiment.

  In step S711, the CPU 101 deletes the environment management information using the same procedure as in step S708 described above, and ends the condition monitoring process according to the second embodiment.

  In the above description, the end of the condition monitoring process may continue the process flow to the start of the condition monitoring process. That is, the CPU 101 of the terminal device 100 may repeatedly execute a series of processing flow from the start to the end shown in FIG. 26, or may be executed when a predetermined condition is fulfilled.

As described above, the file before change stored in the file storage device 200 can be deleted based on the deletion timing set in conjunction with the file change, and the file before change is stored in the file storage device 200. It is possible to effectively suppress the retention. Therefore, the storage capacity of the file storage device 200 can be used effectively.
[Other Embodiments]
In the above-described embodiment, some of the steps described as being executed in the terminal device 100 may be executed in the file storage device 200. For example, step S102 shown in FIG. 15 may be executed by the file storage device 200. In this case, for example, after executing step S101 in the terminal device 100, a registration request signal T103 having no file ID (T1032) is transmitted to the file storage device 200. The file storage device 200 transmits the file identification information generated based on the value indicated in the data block (T1034) of the registration request signal T103 received in step S201 shown in FIG. Thereby, the terminal device 100 can acquire file identification information.

  Further, for example, the process S305 and the process S306 shown in FIG. In this case, for example, the terminal device 100 may transmit the operation history information referred in step S305 to the file storage device 200 at an arbitrary timing before executing the step S305 in the file storage device 200.

  Moreover, all or some of the processes described as being automatically performed among the processes described in the above-described embodiments may be performed manually. Alternatively, all or part of the processing described as being performed manually can be automatically performed by a known method.

  Furthermore, all or any part of the processing performed in each device shown in the present embodiment can be realized as hardware by wired logic.

Claims (7)

A file storage system that stores a backup of a file used in a computer device that provides a file use environment, which is an environment that enables operations on the file, in a storage device that is connected to the computer device via a network. ,
An identification information generating unit for generating file identification information for identifying the file from the content of the file using a hash function;
A backup storage unit that stores a backup of a file identified by the file identification information in association with the file identification information;
A file operation detection unit for detecting the operation of the file;
When the file operation detection unit detects a file operation in the file usage environment, the operation history indicating the operation content of the detected file is displayed for each detected file usage environment. An operation history storage unit that stores the file identification information in association with each other,
When the operation content of the detected file is file deletion, the importance level of the file is acquired based on the operation history stored in the operation history storage unit in association with the file identification information of the file. An importance acquisition unit;
A deletion condition setting unit configured to set a deletion condition of the file that is the target of the detected operation in association with the file identification information of the file based on the acquired importance;
A condition monitoring unit for determining fulfillment of the set deletion condition;
A deletion execution unit that deletes a file corresponding to the deletion condition determined to be fulfilled in the condition monitoring unit, from the backup storage unit;
A file storage system. The file storage system according to claim 1,
An environment management information storage unit for storing environment management information for associating the generated file identification information with the usage environment of the file;
Based on the environment management information indicating the file corresponding to the deletion condition determined to be fulfilled in the condition monitoring unit, it is determined whether there is another usage environment that uses the file, and according to the determination result A deletion permission determination unit that determines whether the file can be deleted;
Have
The deletion condition setting unit sets the deletion condition in association with the file identification information of the file for each use environment of the file,
The deletion execution unit is a file corresponding to the deletion condition determined to be fulfilled by the condition monitoring unit, and deletes the file determined to be deleteable by the deletion permission determination unit from the backup storage unit,
File storage system. The file storage system according to claim 2,
The deletion execution unit invalidates the environment management information stored corresponding to the usage environment corresponding to the deletion condition and the file corresponding to the deletion condition when it is determined that the deletion is not possible in the determination,
The deletion permission / inhibition determining unit determines the determination when valid environment management information indicating another usage environment using a file corresponding to the determined deletion condition is not registered in the environment management information storage unit. It is determined that the file corresponding to the deleted condition can be deleted.
File storage system. The file storage system according to any one of claims 2 to 3,
When the file operation content detected by the file operation detection unit is a file change,
File identification information for identifying the changed file is generated using the identification information generation unit,
Environment management information that associates the file identification information of the generated file after the change with the usage environment of the file is stored in the environment management information storage unit,
A file storage system comprising: an update request execution unit that stores the generated backup of the changed file in the backup storage unit in association with the file identification information of the changed file. The file storage system according to claim 4,
The update request execution unit
When the file operation content detected by the file operation detection unit is a file change,
Obtain the importance of the file before the change using the importance obtaining unit,
Based on the importance of the acquired file before change, the deletion condition of the file before change is set using the deletion condition setting unit,
File storage system. A file storage method for storing a backup of a file used in a computer device that provides a file use environment, which is an environment that enables operations on the file, in a storage device connected to the computer device via a network. ,
File identification information for identifying the file is generated from the content of the file using a hash function,
Storing environment management information for associating the generated file identification information with the usage environment of the file;
A backup of the file identified by the file identification information is stored in association with the file identification information,
When a file operation in the file usage environment is detected, an operation history indicating the operation content of the detected file is stored in association with the file identification information of the detected file for each file usage environment. ,
A case of detecting an operation of the file in the use environment of the file, if the operation contents of the detected file is a file deletion, are store in association to the file identification information of the detected files Based on the operation history, obtain the importance of the detected file,
Based on the acquired importance, set a deletion condition of the file that is the target of the detected operation,
A file storage method for deleting a file corresponding to the deletion condition from the storage device when it is determined that the set deletion condition is fulfilled. A file storage program for storing a backup of a file used in a terminal device that provides a file usage environment, which is an environment that enables operations on the file, in a storage device connected to the terminal device via a network. ,
Computer
An identification information generating unit for generating file identification information for identifying the file from the content of the file using a hash function;
An environment management information storage unit for storing environment management information for associating the generated file identification information with the usage environment of the file;
A backup storage unit that stores a backup of a file identified by the file identification information in association with the file identification information;
When an operation of a file in the file usage environment is detected, an operation history indicating the operation content of the detected file is stored in association with the file identification information of the file for each usage environment of the file. A history storage unit;
When the operation content of the detected file is file deletion, the importance level of the file is acquired based on the operation history stored in the operation history storage unit in association with the file identification information of the file. An importance acquisition unit;
A deletion condition setting unit configured to set a deletion condition of the file that is the target of the detected operation in association with the file identification information of the file based on the acquired importance;
A condition monitoring unit for determining fulfillment of the set deletion condition;
A deletion execution unit that deletes a file corresponding to the deletion condition determined to be fulfilled in the condition monitoring unit from the backup storage unit;
A file storage program that functions as