JP2009003680A - Data transfer system, data transfer method and data transfer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that when a user moves to a location different from a reservation, in other words, when the user moves to an arbitrary location, the user becomes unable to access data for more than a fixed time period. <P>SOLUTION: A data transfer system perceives in advance, disconnection of a wireless network which connects inside of a mobile and outside of the mobile, determines whether a user can access the data which has been transferred after the disconnection of the network, and transfers the data in the mobile to a server out of the mobile if access is impossible. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a data transfer system, a data transfer method, and a data transfer program, and more particularly, to a data transfer system, a data transfer method, and a data transfer program in an environment where the inside and outside of a mobile body are connected by a wireless network.

An example of a conventional data transfer system is disclosed in Japanese Patent Laid-Open No. 2005-148923 (Patent Document 1).
As shown in FIG. 1, the data transfer system includes a home server 10 and a train server 20.

  This data transfer system operates as follows. When train reservation 1 which is a process of reserving a train is performed, schedule reservation-related information 2 is sent to the home server 10 and seat reservation information 3 is sent to the train server 20. Taking into account such information, a schedule is created in the home server 10. Based on the schedule or based on the train reservation 1, the content data is transferred 4 in advance from the home server 10 to the train server 20 before the time when the user gets on the train. After boarding 5, the user can view and edit 6 content and data already transferred to the train server 20 in the train. When getting off, the difference data changed by the editing work is transferred 8 from the train server 20 to the home server.

  The train server 20 is connected to a network outside the train when the train is stopped, and it is assumed that a user (user) in the train cannot communicate with the outside while the train is running. In such an environment, even if the network with the outside is shut off by using this data transfer system, train users will be able to store data that should have been stored outside the train. Be able to access.

  The problem with this technique is that if the user moves to a location different from the reservation, that is, if the user moves to any location other than the reserved location, the data cannot be accessed for a certain period of time. The reason is as follows. This technology is premised on train reservation when determining the data transfer location. In such a situation, if the user gets on a different train from the train reserved by the user, the transferred data may not be accessible.

  As described above, the train server 20 is connected to a network outside the train while the train is stopped, and a user (user) inside the train cannot communicate with the outside while the train is running. Assumed. If communication with the outside is interrupted only while the train is running, the data can be accessed while the train on which the user is riding and the train holding the transferred data are stopped at the station. If the train on which the user is riding or the train holding the transferred data leaves the station, the user cannot access the data. If the data that is the source of transfer remains on the home server, the data on the home server can be transferred to the user's train again, but the data transferred to the train server can be edited. If the data that is the source of the transfer is not left in the home server, the data cannot be accessed until the data transfer schedule created by the train reservation is completed. This technique is not limited to trains, but can be applied to any mobile object that can be reserved, such as a bus or an airplane. However, problems similar to those described above occur.

Japanese Patent Laid-Open No. 2003-216519 (Patent Document 2) discloses an electronic data transfer program.
In this known technique, when the user moves from the B district to the A district, the position detection device that moves with the user detects the movement and transmits information to the transfer instruction device. The transfer instruction device creates a command to transfer the electronic data of the file server in the B district to the file server in the A district, and transmits the command to the file server. As a result, the electronic data is moved to the file server at the position closest to the user.

Furthermore, Japanese Patent Application Laid-Open No. 2004-280281 (Patent Document 3) discloses a data movement system and a data movement method linked to movement of a mobile person.
In this known technique, when a mobile person moves from the A area to the B area on the movement route, when the mobile person starts to move from the A area to the B area on the movement route and passes the boundary point, the mobile person The location information is notified from the mobile communication device to the mobile communication network in the area B by location information notification, and this location information is transmitted to the location information management server by location information notification from the mobile communication network. Further, the location information management server transmits the data of the traveler from the server in the A area to the server in the B area.

JP 2005-148923 A JP 2003-216519 A JP 2004-280281 A

  Detects in advance the disconnection of the wireless network connecting the mobile body and the outside of the mobile body, determines whether the user can access the transferred data even after the network disconnects, and moves if the access is not possible If the data in the body can be transferred to a server outside the mobile body, it is considered that the problems described in the background art can be solved.

  In the following, means for solving the problem will be described using the numbers used in [Best Mode for Carrying Out the Invention] in parentheses. These numbers are added to clarify the correspondence between the description of [Claims] and [Best Mode for Carrying Out the Invention]. However, these numbers should not be used to interpret the technical scope of the invention described in [Claims].

  The data transfer system of the present invention measures the position of each device (100, 300) connected to each other, calculates the moving direction and moving speed of each device (100, 300), and each device (100, 300). When the distance between the position measuring unit (110, 210, 310) that measures the distance between the devices and each device (100, 300) exceeds a predetermined threshold, a disconnect warning is determined to determine that there is a possibility of network disconnection. When the moving direction or moving speed of the unit (240) is different from that of the devices (100, 300) and the disconnection warning transmission unit (240) notifies that there is a possibility of network disconnection, each device (100, 300) A data movement determination unit (320) for determining whether or not it is necessary to move the data in the data server (300) that is one of the data server (300) to another location (400, 700); When it is necessary to move the data in (300) to another location (400, 700), a data dropping unit (330) for moving the data in the data server (300) to another location (400, 700) It comprises. In addition, each apparatus (100, 300) to move may point to the access point (500) in the mobile body (600) or the mobile body (600). In this case, the position measuring unit (110, 310) indicates the position measuring unit (510).

  The data movement determination unit (320) does not need to move the data in the data server (300) to another location (400, 700) when the movement direction and movement speed of each device (100, 300) are the same. judge.

  The disconnect warning transmission unit (240) restricts the determination on the possibility of network disconnection when the moving direction and moving speed of each device (100, 300) are the same.

  The data transfer system of the present invention includes a temporary server (700) for storing data in the data server (300), and a storage area for storing information on the capacity and usage status of the temporary server (700) in a storage area management table A search unit (270) and a storage area management unit (250) for referring to the storage area management table and providing information on the temporary server (700) to the data dropping section (330) are further provided.

  The data transfer system according to the present invention includes a drop priority calculation unit (370) that calculates a data movement order when data in the data server (300) is moved to another location (400, 700), A drop order list (380) for storing the movement order is further provided. The data drop unit (330) moves the data according to the data movement order.

  Data can be accessed even if the data server moves to any location. The reason is that when the data server starts moving to a location that the user cannot access, the data server moves the data that it holds to a location that the user can access, so that the user can access the file. Can do. That is, there is no need to wait for access to data until the data transfer schedule based on the boarding reservation is completed.

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the accompanying drawings.
Referring to FIG. 2, the data transfer system of the present invention includes a user PC 100, an access point 200, a data server 300, and an access point server 400. A plurality of these devices may be provided.

  The user PC 100 is a terminal for referring to and editing data. The access point 200 is a device for connecting the user PC 100 and the data server 300 to a network outside the mobile unit. In many cases, there are a plurality of access points 200. In this case, the access point 200 connected to the user PC 100 and the access point 200 connected to the data server 300 may be different devices. The data server 300 is a device for storing data to be edited by a user. The user PC 100 and the data server 300 are arranged inside a moving body such as a train or an aircraft. The access point server 400 is a data storage device attached to the access point 200.

  The user PC 100 includes a position measurement unit 110. The access point 200 includes a position measurement unit 210, a position information management unit 220, a position information storage unit 230, and a disconnect warning transmission unit 240. The data server 300 includes a position measurement unit 310, a data movement determination unit 320, a data throwing unit 330, a user access storage unit 340, an access point server storage unit 350, and a user data storage unit 360. The access point server 400 includes a user data storage unit 410 and a data transfer unit 420.

  The position measuring units 110, 210, and 310 are arranged one by one on a device that needs to measure the position, periodically measure the position of the device on which the position measuring unit is disposed, and calculate the moving speed and moving direction of the device. To do. In addition, when communication with other position measurement units (position measurement units 110, 210, 310 other than itself) is possible, by transmitting / receiving signals to / from other position measurement units, Measure the distance between.

  The location information management unit 220 stores the location information acquired by the location measurement units 110, 210, and 310 in the location information storage unit 230. At this time, if there is information on the moving speed or moving direction, it is stored in association with it.

  The position information storage unit 230 is a storage area for storing information obtained by the position measurement unit 210. The position information storage unit 230 has an identifier 231 and a distance 232. The identifier 231 is a value that uniquely represents the device in which the position measurement units 110 and 310 to be measured are arranged. A distance 232 represents a distance between the devices. If there is information on the moving speed or moving direction, it is similarly stored.

FIG. 3 shows an example of the position information storage unit 230.
In FIG. 3, a device name is used as the identifier 231. However, the identifier 231 may be anything such as an IP address or a host name as long as it can uniquely identify the device. In FIG. 3, the distance 232 between the access point 200 and the data server 300 is 10 m, and the distance 232 between the access point 200 and the user PC 100 is 20 m.

  When the distance 232 stored in the position information storage unit 230 exceeds a certain value (threshold value), the disconnection warning transmission unit 240 determines that there is a possibility of network disconnection, and the data movement determination unit 320 It notifies the possibility of network disconnection. At this time, it is assumed that a certain value (threshold value) is given by the user. Note that if the movement direction or movement speed of the user PC 100 or the data server 300 is different, the disconnection warning transmission unit 240 determines the possibility of network disconnection, and the movement direction and movement speed of the user PC 100 or the data server 300 are determined. If they are the same, it can be considered that the user PC 100 and the data server 300 are determined to be in the same mobile body, and the possibility of network disconnection is not determined. That is, if the moving direction and moving speed of the user PC 100 and the data server 300 are the same, the determination on the possibility of network disconnection is limited. Alternatively, if the moving direction and moving speed of the user PC 100 and the data server 300 are the same, it may be determined that there is no possibility of network disconnection.

  The data movement determination unit 320 determines whether or not the data in the data server 300 needs to be moved to another location after being notified by the disconnection warning transmission unit 240 that there is a possibility of network disconnection. Information stored in the position information storage unit 230 is used for the determination. In the determination, the “distance between the access point 200 and the data server 300” is compared with the “distance between the access point 200 and the user PC 100”. If they are the same, it is not necessary to move the data in the data server 300 to another location. Leave it as it is. If not, it is determined that the data in the data server 300 needs to be moved to another location. That the two distances 232 are the same means that the data server 300 and the user PC 100 exist in the same place, that is, the same device. Since the present invention regards the user PC 100 and the data server 300 as different devices, an appropriate approximation can be made when making a comparison depending on the installation location of each device in the moving body, the measurement error of the position measuring units 110, 210, 310, and the like. Need to give. For example, when the distance 232 between the access point 200 and the data server 300 is 10 m and the distance 232 between the access point 200 and the user PC 100 is 13 m, the measurement error of the position measuring units 110, 210, and 310 is ± 2 m. Are compared with each other, it is determined that “distance 232 is the same”.

  In addition, the position measurement unit 110, 210, 310 acquires the moving direction or the like of the moving body as information, so that the determination system of the data movement determination unit 320 can be enhanced. For example, even when the distance between the user PC 100 and the data server 300 changes, there is a possibility that the user PC 100 and the data server 300 are in the same moving body and only one or both of them are moved in the same moving body. Therefore, if the moving direction of the user PC 100 (or moving body) acquired by the position measuring unit 110 and the moving direction of the data server 300 (or moving body) acquired by the position measuring units 110, 210, and 310 are the same, the data The movement determination unit 320 determines that the user PC 100 and the data server 300 are in the same moving body, and it is not necessary to move the data in the data server 300 to another location.

  Further, the determination system of the data movement determination unit 320 can be further enhanced by referring to the movement direction and the change in the movement speed and distance. For example, when the movement direction of the user PC 100 and the data server 300 is the same and the movement speed or distance changes temporarily, the data movement determination unit 320 moves the data in the data server 300 to another location. Judge that it is not necessary. Even if the movement direction is the same, if the movement speed and the distance continue to change, it is determined that the user PC 100 and the data server 300 are in different moving bodies, and the data in the data server 300 needs to be moved to another location. To do. It is preferable that the change in the moving speed and the distance is a change so large that it is understood that there is no measurement error. In order to determine whether changes in movement speed or distance are temporary, it is necessary to periodically monitor changes in movement speed or distance. However, if the monitoring time interval is large, data movement will be in time. There is a possibility of disappearing. In view of this, it is conceivable to shorten the monitoring time interval from when the change in the moving speed or the distance is first detected. For example, the position measuring units 110, 210, and 310 usually monitor at intervals of 5 minutes, and when a change in movement speed or distance is detected, monitoring is performed at intervals of 10 seconds for only one minute. When the change in the distance is detected a predetermined number of times, the data movement determination unit 320 determines that the data in the data server 300 needs to be moved to another location. During this time (one minute), if the movement speed or distance change is not detected a predetermined number of times, the movement speed or distance change is temporary, and the data in the data server 300 needs to be moved to another location. Judge that there is no. Thereafter, it is monitored again at 5-minute intervals.

  That is, the content that the data movement determination unit 320 determines is “whether the data and the user are moving together”. If the data and user appear to be moving together, there is no need to transfer the data to another location. Without the data movement determination unit 320, data transfer is repeated at a place where data is transferred to an inaccessible place or where the network is disconnected and connected repeatedly. As a means for reducing the “fixed time” as much as possible, the data movement determining unit 320 uses a wasteful data transfer time for the problem that “when moving to an arbitrary place, data cannot be accessed for a fixed time or longer”. It is thought to be effective in the sense of eliminating

  The data dropping unit 330 moves the data to the access point server 400 when the data movement determining unit 320 determines that the data existing in the data server 300 needs to be moved. For example, data is moved to the access point server 400 in accordance with a data movement instruction from the data movement determination unit 320 or a notification that data movement is necessary. First, the data dropping unit 330 creates a transfer data list 430 described later and stores it in the user data storage unit 410 of the access point server 400. In the background art, a train is taken as an example, but a moving body including a train passes through the access points 200 installed in various places during the movement. In addition, the time that can be connected to the access point 200 is limited, and the movement of data is not always completed while connected to the access point 200. In such a case, data is moved to the access point server 400 as much as possible while connected to the access point 200, and after disconnection, the data is moved to the next access point server 400 at the next access point 200. Will do. Therefore, the data dropping unit 330 distributes data to the access point servers 400 arranged at each access point 200.

  The transfer data list 430 is header information necessary for collecting data distributed and arranged in each access point server 400 in one place. Any structure and processing procedure of the header information may be used as long as the distributed data can be collected in one place. Here, a description will be given using a link list as an example.

FIG. 4 shows an example of the transfer data list 430.
The transfer data list 430 has a user name 431, an element number 432, and a pointer 433 as elements. One transfer data list 430 is arranged in each access point server 400. In the first access point 200 that starts data movement, a transfer data list having “1” in the element number 432 and “HEAD” in the pointer 433 as shown in the transfer data list 430 (A) in the figure. 430 is placed in the access point server 400. In the next access point 200, as in the transfer data list 430 (B) in the figure, the element number 432 has “2”, and the pointer 433 has the name of the access point server that was connected last time as an element. It will be. The name of the access point server connected last time is acquired from the access point server storage unit 350. The element number 432 of the last transfer data list 430 has an element “TAIL”. Next, when the data server 300 is communicable with the access point 200, the data is continuously moved to the access point server 400 while communication is possible. If the network is disconnected while the data is being moved to the access point server 400, the state up to the time when the data movement is completed is temporarily stored and arrives at the access point 200 at another location. When the network connection is restored, the data movement is resumed from the temporarily stored state.

  The user access storage unit 340 stores an identifier 231 of a device that is accessing the data server 300. The identifier 231 here may be anything such as an IP address or a host name as long as it can uniquely identify the device.

  The access point server storage unit 350 is a storage area for storing the history of the access point 200 to which the data server 300 was connected, and the access point names are stored in chronological order. The history of the access point 200 accumulated in the access point server storage unit 350 is used when the data dropping unit 330 creates the transfer data list 430.

  User data storage units 360 and 410 are areas for storing transfer data list 430 and user data, and are arranged in data server 300 and access point server 400, respectively. The user data storage unit 360 stores data to be moved to another location by the data projecting unit 330.

  The data transfer unit 420 is a means for collecting data distributed and arranged in each access point server 400 at one place. Each access point server 400 having distributed data holds a transfer data list 430. The data transfer unit 420 transfers the data held by itself to the access point server 400 indicated by the pointer 433 of the transfer data list 430. Eventually, the data is collected in the access point server 400 in which the transfer data list 430 having “HEAD” as the pointer 433 exists. When the access point server 400 having a list having an element of “TAIL” in the element number 432 completes the data transfer, the access point server 400 notifies the access point server 400 indicated by the pointer 433 that the data transfer is completed, and transfers the transfer data. The list 430 is deleted. The access point server 400 notified of the completion of the data transfer rewrites the element number 432 of its own transfer data list 430 to “TAIL”. By repeating this operation, data is collected into “HEAD”.

Next, operations during data movement will be described in detail with reference to the flowcharts of FIGS. 5A and 5B and FIG.
First, refer to FIG. 5A.
(1) Step S101
The disconnect warning transmission unit 240 notifies the data movement determination unit 320 of the possibility of network disconnection. Before the notification, the access point 200 measures the distance 232 between the user PC 100 and the data server 300 by the position measurement units 110, 210, and 310 in advance, and the measurement information is stored in the position information storage unit 230. Shall. Further, it is assumed that the disconnect warning transmission unit 240 constantly monitors whether the stored distance 232 exceeds the threshold value given by the user.
(2) Step S102
The data movement determination unit 320 accesses the user access storage unit 340 and acquires the identifier 231 of the user PC 100 that is accessing the file.
(3) Step S103
The data movement determination unit 320 acquires distance information corresponding to the acquired identifier 231 of the user PC 100 from the position information storage unit 230.
(4) Step S104
The data movement determination unit 320 compares whether the “distance 232 between the data server 300 and the access point 200” and the “distance 232 between the user PC 100 and the access point 200” are the same. The “distance 232 between the data server 300 and the access point 200” is acquired from the position information storage unit 230 in the same manner as the “distance 232 between the user PC 100 and the access point 200”. If the “distance 232 between the data server 300 and the access point 200” and the “distance 232 between the user PC 100 and the access point (AP) 200” are the same, the file is not moved, and the process ends.
(5) Step S105
If the “distance 232 between the data server 300 and the access point 200” is different from the “distance 232 between the user PC 100 and the access point 200”, the data movement determination unit 320 creates the first transfer data list 430.
(6) Step S106
The data movement determination unit 320 copies the transfer data list 430 to the access point server 400.
(7) Step S107
The data movement determination unit 320 starts moving data to the access point server 400.
(8) Step S108
The data dropping unit 330 continues to move data until the network is disconnected. If the network between the data server 300 and the access point 200 is not disconnected, the data movement is completed and the process is terminated.
(9) Step S109
When the network is disconnected, the location information storage unit 230 stores the identifier 231 (host name, IP, etc.) of the access point server 400 that has moved the data until the network connection is restored at the destination. stand by.

Reference is now made to FIG.
(10) Step S110
The data dropping unit 330 immediately after the end of the flowchart shown in FIG. 5A is in a state of waiting for the network connection with the access point 200 to be restored.
(11) Step S111
When the network connection is restored, the data dropping unit 330 creates the transfer data list 430 using the previous connection location as the pointer 433. The previous connection location is the access point server 400 accessed before disconnection, and the transfer data list 430 having the identifier 231 of the access point server 400 as the pointer 433 is created. The element number 432 of the transfer data list 430 is the number of times the network is reconnected + 1.
(12) Step S112
The data dropping unit 330 copies the transfer data list 430 to the new access point server 400.
(13) Step S113
The data dropping unit 330 moves the remaining data to the access point server 400.
(14) Step S114
These processes are repeated until there is no data to be moved.
(15) Step S115
The data dropping unit 330 rewrites the element number 432 of the transfer data list 430 stored in the access point server 400 to “TAIL” if the network is not disconnected until the data movement to the access point server 400 is completed. The process is terminated.

Reference is now made to FIG.
FIG. 6 is a flowchart showing the state transition of the data transfer unit 420. The data transfer unit 420 starts processing when the network connection between the access point 200 and the data server 300 is disconnected.
(1) Step S116
The data transfer unit 420 transfers data to the access point server 400 indicated by the pointer 433.
(2) Step S117
The data transfer unit 420 continues until the transfer of the stored data is completed.
(3) Step S118
The data transfer unit 420 determines whether the element number 432 is “TAIL”.
(4) Step S119
If the element number 432 is not “TAIL”, the data transfer unit 420 waits because the data moved to the access point server 400 at the next destination is to be transferred.
(5) Step S120
If the element number 432 is “TAIL”, the data transfer unit 420 notifies the connection destination access point server 400 that the data transfer has been completed.
(6) Step S121
The data transfer unit 420 deletes the transfer data list 430 and ends the process.

  The access point server 400 notified of the completion of the data transfer rewrites the element number 432 of its own transfer data list 430 to “TAIL”. By repeating the processing of FIG. 6, the data is finally aggregated to the first access point server 400 that has started moving data from the data server 300 to the access point server 400.

  In this embodiment, before the network connection between the access point 200 and the data server 300 is cut off, the data is moved to a place (access point server 400) where the user can access as much as possible. The time when it cannot be shortened.

  In the above-described embodiment, it is determined that the data server 300 and the user PC 100 are moving together by measuring only the distance 232. Since this does not include the moving direction, if there are two moving objects moving in the opposite direction at the same speed, the data moving command by the data movement determining unit 320 is not notified to the data throwing unit 330. In order to prevent such a situation, the position measuring units 110, 210, and 310 that can acquire the moving direction in addition to the distance are preferably arranged in the access point 200, the user PC 100, and the data server 300. By doing so, more accurate movement determination can be performed. Specifically, a position information acquisition device such as GPS is raised. If the direction can be added to the position information, the process of “Step S104” is added with the condition “the direction is the same” in addition to the condition “the distance 232 is the same”.

  In the above embodiment, it is determined that the data server 300 and the user PC 100 are moving together by measuring only the distance 232, but the history of the measured distance 232 is stored in the position information storage unit 230. In addition, by causing the position information management unit 220 to calculate the “movement amount in a certain time”, the accuracy of the movement determination of the data movement determination unit 320 can be further increased. If the movement amount can be added to the position information, the process of “Step S104” is not “the distance 232 is the same” but “the movement amount is the same”.

  In the above embodiment, the user PC 100 and the data server 300 are directly connected to the access point 200. However, as shown in FIG. 7, the mobile PC 600 (600-i, i = 1 to n: n is arbitrary) In a communication system in which a mobile access point 500 (500-i, i = 1 to n) is installed in the mobile body and the mobile access point 500 is connected to an access point 200 installed outside the mobile body. Also, the present invention can be applied. In such a case, the position measuring unit 510 is installed at the access point 500 in the moving body, and the distance 232 to the access point 200 outside the moving body is measured. Even in that case, the processing procedure of the present invention itself is not changed. The mobile access point 500 may be an apparatus having the same configuration as the access point 200.

Next, a second embodiment of the present invention will be described in detail with reference to the accompanying drawings.
Referring to FIG. 8, in the second embodiment of the present invention, a temporary server 700 (700-i, i = 1 to n: n is arbitrary) is added instead of the access point server 400 in the first embodiment. . The temporary server 700 includes a user data storage unit 710, a data transfer unit 720, and a storage area providing unit 730. Further, in addition to the components of the access point 200 in the first embodiment, a storage area management unit 250, a storage area management table 260, and a storage area search unit 270 are newly added to the access point 200. In this case, the access point 200 includes a position measurement unit 210, a position information management unit 220, a position information storage unit 230, a disconnect warning transmission unit 240, a storage area management unit 250, a storage area management table 260, a storage An area search unit 270 is provided.

  Temporary server 700 is a storage area for moving user data from data server 300 instead of access point server 400. The access point server 400 is permanently installed in the access point 200 and is a dedicated server for moving data from the data server 300. On the other hand, the temporary server 700 is lent from the owner of the server by a part of the storage area in an idle state from a personal computer or a workstation. Therefore, when the owner uses the temporary server 700, the number of temporary servers 700 and the storage capacity vary with time. A computer such as a personal computer or a workstation is provided with the data transfer unit 420 and the storage area providing unit 730, thereby becoming the temporary server 700 in the present invention.

  The storage area providing unit 730 stores that there is an area that can be provided as a data movement destination of the data projecting unit 330 among the storage areas of the temporary server 700 in which the storage area providing unit 730 is installed, that is, the user data storage unit 710 exists. The area search unit 270 is notified. It is assumed that the storage area providing unit 730 knows in advance where the storage area searching unit 270 exists. Further, when the user data storage unit 710 that can be provided is used by the owner of the temporary server 700, the storage area search unit 270 is notified that the user data storage unit 710 has become unusable. . However, if the data has already been moved to the user data storage unit 710 by the data dropping unit 330, the owner of the temporary server 700 cannot use the user data storage unit 710.

  The storage area management unit 250 provides information of the temporary server 700 that can move data from the data server 300 to the data dropping unit 330. The storage area management unit 250 selects and provides the server name 261 and the total capacity 262 as information on the temporary server 700 from the storage area management table 260.

  The storage area management table 260 is a table for storing a list of user storage areas provided from the temporary server 700.

FIG. 9 shows an example of the storage area management table 260.
The storage area management table 260 includes a server name 261, a total capacity 262, a usage amount 263, and a status 264. The server name 261 indicates identification information of the data server 700. The total capacity 262 indicates the total capacity of the user data storage unit 710. The usage amount 263 indicates the capacity used by the data server 300 in the user data storage unit 710 for data movement. The state 264 indicates a state in which the data server 300 is using or can use the user data storage unit 710 for data movement.

  As for the usage amount 263, a numerical value is entered when it is used, and “N / A” is entered when it is not used. There are three types of status 264: “in use”, “available”, and “unusable”. “In use” indicates a state in which data is being transferred from the data server 300 to the temporary server 700. “Usable” indicates a state in which the temporary server 700 can provide a difference amount between the total capacity 262 and the usage amount 263 in response to a request from the data dropping unit 330. “Unusable” indicates a state in which the difference between the total capacity 262 and the usage amount 263 is 0 or almost used, and the temporary server 700 cannot be provided in response to a request from the data launching unit 330.

  The storage area search unit 270 stores information regarding the user data storage unit 710 sent from the storage area providing unit 730 in the storage area management table 260.

  Next, the overall operation of the present exemplary embodiment will be described in detail with reference to the flowcharts of FIGS. 10A and 10B.

First, the flowchart of FIG. 10A will be described.
(1) Step S201
The disconnect warning transmission unit 240 notifies the data movement determination unit 320 of the possibility of network disconnection. Before the notification, it is assumed that the access point 200 measures the distance 232 between the user PC 100 and the data server 300 in advance by the position measurement unit 310, and the measurement information is stored in the position information storage unit 230. Further, it is assumed that the disconnect warning transmission unit 240 constantly monitors whether the stored distance 232 exceeds the threshold value given by the user.
(2) Step S202
The data movement determination unit 320 accesses the user access storage unit 340 and acquires the identifier 231 of the user PC 100 that is accessing the file.
(3) Step S203
The data movement determination unit 320 acquires distance information corresponding to the acquired identifier 231 of the user PC 100 from the position information storage unit 230.
(4) Step S204
The data movement determination unit 320 compares whether the “distance 232 between the data server 300 and the access point 200” and the “distance 232 between the user PC 100 and the access point 200” are the same. The “distance 232 between the data server 300 and the access point 200” is acquired from the position information storage unit 230 in the same manner as the “distance 232 between the user PC 100 and the access point 200”. If the “distance 232 between the data server 300 and the access point 200” and the “distance 232 between the user PC 100 and the access point (AP) 200” are the same, the file is not moved, and the process ends.
(5) Step S205
When the distances 232 between the user PC 100, the data server 300, and the access point 200 are different, the data movement determination unit 320 instructs the data transfer unit 330 to move the data. The data dropping unit 330 requests information on the temporary server 700 from the storage area management unit 250 arranged in the access point 200. In this processing, the data dropping unit 330 notifies the storage area management unit 250 of the capacity of the user data storage unit 710 of the temporary server 700 necessary for moving the data. The storage area management unit 250 selects one or a plurality of temporary servers 700 having the required capacity and whose status 264 is “available” from the storage area management table 260, and selects the selected temporary server 700. The server name 261 is transmitted to the data release unit 330. Further, the storage area management unit 250 changes the state 264 of the selected temporary server 700 in the storage area management table 260 from “available” to “in use”.
(6) Step S206
The data dropping unit 330 creates a transfer data list 430 for each temporary server 700.
(7) Step S207
The data dropping unit 330 copies the transfer data list 430 to the temporary server 700. When there are a plurality of temporary servers 700, the transfer data list 430 is copied to the temporary server 700 in an appropriate order. The transfer data list 430 to be copied here does not have the same transfer data list 430 for all the temporary servers 700 but forms a link list as described in the first embodiment. Therefore, the transfer data list 430 has different element numbers 432 and pointers 433 depending on each temporary server 700.
(8) Step S208
Then, the data dropping unit 330 copies the data to the temporary server 700.
(9) Step S209
Here, if the network between the data server 300 and the access point 200 is not disconnected, the data dropping unit 330 continues the process and ends.
(10) Step S210
When the network is disconnected, the data dropping unit 330 changes the state 264 of the temporary server 700 that has not been used as a data storage area to “usable” or “unusable”. When this step is detailed, first, the access point 200 that knows that the network has been disconnected notifies the storage area search unit 270 that the network has been disconnected. The storage area searching unit 270 notifies the storage area providing unit 730 of the temporary server 700 whose status 264 is “in use” among the entries of the storage area management table 260 that the network has been disconnected. The storage area providing unit 730 notifies the storage area searching unit 270 of the usage amount 263 of the user data storage unit 710 of the temporary server 700 in which the storage area providing unit 730 is arranged. The storage area search unit 270 that has received the usage amount 263 of each temporary server 700 rewrites the state 264 to “usable” or “unusable” according to the usage amount 263 of each temporary server 700. The determination criterion of the state transition is the difference between the total capacity 262 and the usage amount 263 of each temporary server 700. If the usable user data storage unit 710 still remains, it can be “useable”, and if it does not remain, “unusable” "
(11) Step S211
Finally, the location information storage unit 230 stores the identifier 231 of the temporary server 700.

Next, the flowchart of FIG. 10B will be described.
(12) Step S212
The data dropping unit 330 immediately after the end of the flowchart shown in FIG. 10A is in a state of waiting for the network connection with the access point 200 to be restored.
(13) Step S213
Then, when the network connection is restored (S10), the data dropping unit 330 acquires information of the temporary server 700 at the new access point 200 (S27). The information acquisition method of the temporary server 700 is as described in the flowchart of FIG. 10A.
(14) Step S214
The data dropping unit 330 creates the transfer data list 430 using the previous connection location as the pointer 433. The previous connection location is the temporary server 700 accessed before disconnection, and the transfer data list 430 having the identifier 231 of the temporary server 700 as the pointer 433 is created.
(15) Step S215
The data dropping unit 330 copies the transfer data list 430 to the new temporary server 700.
(16) Step S216
In addition, the data dropping unit 330 moves the remaining data to the temporary server 700.
(17) Step S217
These processes are repeated until there is no data to be moved.
(18) Step S218
If there is no disconnection of the network until the data transfer to the temporary server 700 is completed, the data dropping unit 330 sets the largest number among the element numbers 432 of the transfer data list 430 stored in each temporary server 700 as “ The process ends after rewriting to "TAIL" (S15).

  In this embodiment, instead of providing a dedicated server called the access point server 400, by replacing the temporary server 700, a large amount of data that could not be transferred from the data server 300 to the access point server 400 is transferred to the temporary server 700. Can be moved.

  In the above embodiment, as shown in FIG. 11, the hop count 265 from the access point 200 to the temporary server 700 can be added to the storage area management table 260 as an entry. In this case, the storage area management table 260 includes a server name 261, a total capacity 262, a usage amount 263, a status 264, and a hop count 265. The number of hops 265 indicates the number of times that a router passes when a certain server and a certain server perform network communication. Thereby, when acquiring information of the temporary server 700, the temporary server 700 closer to the access point 200 can be selected, and the network delay related to the movement and transfer of data can be reduced.

Next, a third embodiment of the present invention will be described in detail with reference to the accompanying drawings.
Referring to FIG. 12, in the third embodiment of the present invention, the data server 300 includes a drop priority calculation unit 370 and a drop order list 380 in addition to the components of the data server 300 in the first embodiment. To join. In this case, the data server 300 includes a position measurement unit 310, a data movement determination unit 320, a data drop unit 330, a user access storage unit 340, an access point server storage unit 350, a user data storage unit 360, a drop A priority calculation unit 370 and a drop order list 380 are provided.

  The drop priority calculation unit 370 is a means for calculating the data movement order when the data drop unit 330 moves data from the data server 300 to the access point server 400. The drop priority calculation unit 370 calculates the data movement order before the data movement starts and stores it as a drop order list 380. The data drop unit 330 moves the data to the access point server 400 according to the drop order list 380. The priority of data movement is calculated using accumulated information such as the number of times of browsing the data, the update frequency, and the execution time.

  The drop order list 380 is a list that describes the order of movement of data to be moved to the access point server 400. For example, if the movement unit of the data to be moved is “for each file”, the drop order list 380 is a list in which the file names are arranged in the movement order.

  Each of the above embodiments can be implemented in combination.

  In an environment where a moving body such as a vehicle (train, car, etc.) or an airplane and the outside of the moving body are connected by a wireless network, the present invention detects the disconnection of the wireless network in advance and moves. Allows data in the body to be transferred to a server outside the mobile.

  According to the present invention, since data can be distributed in a home server or a computer that receives data from a data center, a place where data is fixedly accumulated, such as a home server or a data center, is required. It will not be.

  As described above, in the present invention, the access point 200 includes the position measurement unit 210 and the disconnection warning transmission unit 240, the data server 300 includes the position measurement unit 310, and the data movement determination unit 320. Is provided with a position measuring unit 110.

  The access point 200 includes a position measurement unit 210 and a disconnect warning transmission unit 240, the data server 300 includes a position measurement unit 310 and a data movement determination unit 320, and the user PC 100 includes a position measurement unit 110. It is characterized by that.

  The access point 200 always monitors the distance between the data server 300 and each user PC 100 using the position measurement unit 210. Then, if the distance between the data server 300 and the access point 200 becomes longer, the disconnect warning transmission unit 240 is used to warn the data server 300 that there is a possibility that the network connection may be disconnected. The data server 300 that has received the warning uses the data movement determination unit 320 to determine whether or not the data stored in the data server 300 needs to be moved to another location. When the data server 300 is moving in the same direction and at the same speed as the user PC 100, it is estimated that the user PC 100 and the data server 300 exist in the same moving body, and the user PC 100 and the data in the same moving body. The server 300 can access the file by performing direct communication without going through the access point 200. Therefore, it is not necessary to move the data stored in the data server 300 to another place, and the state is maintained as it is. When the data server 300 is moving in a different direction from the user PC 100 at different speeds, the user PC 100 and the data server 300 are estimated to be arranged in different moving bodies and stored in the data server 300. Move data to a server installed outside the moving body.

  Adopting such a configuration, detecting in advance the disconnection of the wireless network connecting the mobile body and the outside of the mobile body to determine whether the user can access the transferred data even after the network disconnection, Provided is a data transfer system capable of transferring data in a mobile body to a server outside the mobile body if access is impossible.

FIG. 1 is a block diagram showing a configuration of a known technique. FIG. 2 is a block diagram showing the configuration of the first embodiment of the present invention. FIG. 3 is a block diagram illustrating a configuration of the position information storage unit. FIG. 4 is a block diagram showing the configuration of the transfer data list. FIG. 5A is a first flowchart showing the operation of the first embodiment. FIG. 5B is a second flowchart showing the operation of the first embodiment. FIG. 6 is a flowchart showing the operation of the data transfer unit. FIG. 7 is a block diagram showing a modification of the first embodiment of the present invention. FIG. 8 is a block diagram showing the configuration of the second embodiment of the present invention. FIG. 9 is a block diagram showing the configuration of the storage area management table. FIG. 10A is a first flowchart showing the operation of the second embodiment. FIG. 10B is a second flowchart showing the operation of the second embodiment. FIG. 11 is a block diagram showing a modification of the storage area management table in the second embodiment of the present invention. FIG. 12 is a block diagram showing the configuration of the third embodiment of the present invention.

Explanation of symbols

1 Home Server 2 Train Reservation 3 Train Server 4 Seat Reservation 5 Data Transfer 6 Ride 7 Ride Data Edit 8 Get Off 9 Data (Difference) Transfer 100 User PC
DESCRIPTION OF SYMBOLS 110 Position measurement part 200 Access point 210 Position measurement part 220 Position information management part 230 Position information storage part 231 Identifier 232 Distance 240 Disconnection warning transmission part 250 Storage area management part 260 Storage area management table 261 Server name 262 Total capacity 263 Usage amount 264 State 265 Number of hops 270 Storage area search unit 300 Data server 310 Position measurement unit 320 Data movement determination unit 330 Data drop unit 340 User access storage unit 350 Access point server storage unit 360 User data storage unit 370 Drop priority calculation unit 380 Drop order List 400 Access point server 410 User data storage unit 420 Data transfer unit 430 Transfer data list 431 User name 432 Element number 433 Pointer 500 (-i, i = 1 to n) Mobile access point 510 (-i, i = 1 to n) Position measuring unit 600 (-i, i = 1 to n) Mobile body 700 (-i, i = 1 to n) Temporary server 710 (-i, i) = 1 to n) User data storage unit 720 (-i, i = 1 to n) Data transfer unit 730 (-i, i = 1 to n) Storage area providing unit

Claims (17)

A position measuring unit that measures each position of devices connected to each other, calculates a moving direction and a moving speed of each device, and measures a distance between the devices;
When the distance between the devices exceeds a predetermined threshold, a disconnection warning transmission unit that determines that there is a possibility of network disconnection,
When the moving direction or moving speed of each device is different and the disconnect warning sending unit notifies that there is a possibility of network disconnection, the data in one of the devices is transferred to another location. A data movement determination unit for determining whether it is necessary to move, and
A data transfer system comprising: a data dropping unit for moving data in the data server to another location when the data in the data server needs to be moved to another location. The data transfer system according to claim 1,
The data transfer determination unit determines that it is not necessary to move data in the data server to another location when the movement direction and movement speed of each device are the same. The data transfer system according to claim 1 or 2,
The disconnection warning transmission unit restricts the determination about the possibility of network disconnection when the moving direction and moving speed of the devices are the same. The data transfer system according to any one of claims 1 to 3,
A temporary server for storing data in the data server;
A storage area search unit for storing information on the capacity and usage status of the temporary server in a storage area management table;
A data transfer system, further comprising: a storage area management unit that refers to the storage area management table and provides information on the temporary server to the data drop section. The data transfer system according to any one of claims 1 to 4,
When moving the data in the data server to another location, a drop priority calculation unit that calculates the movement order of the data,
A drop order list for storing the movement order of the data;
The data drop unit is a data transfer system that moves data according to a movement order of the data. A position measuring unit for measuring positions of devices connected to each other, calculating a moving direction and a moving speed of each device, and measuring a distance between each device;
A position information management unit that stores the position, moving direction, moving speed, and distance between each device in association with the identification information of each device;
An access point comprising: a disconnection warning transmission unit that determines that there is a possibility of network disconnection when the moving direction or moving speed of each device is different and the distance between each device exceeds a predetermined threshold. A location measurement unit that notifies location information to an access point that relays communication with the terminal;
If the distance between the terminal and the access point is different from the access point when the distance to the access point exceeds a predetermined threshold and the access point is notified that there is a possibility of network disconnection, A data movement determination unit that determines whether it is necessary to move to a place;
A data server comprising: a data projecting unit that moves the held data to another location when the held data needs to be moved to another location. Measuring the position of each device connected to each other, calculating the moving direction and moving speed of each device, and measuring the distance between the devices;
Determining that there is a possibility of network disconnection when the distance between the devices exceeds a predetermined threshold;
When the moving direction or moving speed of each device is different and the disconnect warning sending unit notifies that there is a possibility of network disconnection, the data in one of the devices is transferred to another location. Determining whether it needs to be moved;
And a step of moving the data in the data server to another location when the data in the data server needs to be moved to another location. The data transfer method according to claim 8, wherein
A data transfer method further comprising the step of determining that the data in the data server does not need to be moved to another location when the moving direction and moving speed of the devices are the same. The data transfer method according to claim 8 or 9, wherein
A data transfer method further comprising a step of restricting determination as to the possibility of network disconnection when the moving direction and moving speed of each device are the same. The data transfer method according to any one of claims 8 to 10,
Storing information on the capacity and usage status of a temporary server for storing data in the data server in a storage area management table;
Storing the data in the data server in the temporary server according to the storage area management table. A data transfer method according to any one of claims 8 to 11,
Calculating the data movement order when moving the data in the data server to another location;
A data transfer method further comprising the step of moving data according to the order of movement of the data. Measuring the position of each device connected to each other, calculating the moving direction and moving speed of each device, and measuring the distance between the devices;
Determining that there is a possibility of network disconnection when the distance between the devices exceeds a predetermined threshold;
When the moving direction or moving speed of each device is different and the disconnect warning sending unit notifies that there is a possibility of network disconnection, the data in one of the devices is transferred to another location. Determining whether it needs to be moved;
A data transfer program comprising: a step of moving data in the data server to another location when the data in the data server needs to be moved to another location. A data transfer program according to claim 13, comprising:
A data transfer program, further comprising the step of determining that the data in the data server does not need to be moved to another location when the moving direction and moving speed of the devices are the same. The data transfer program according to claim 13 or 14,
A program for data transfer, further comprising a step of restricting determination as to the possibility of network disconnection when the moving direction and moving speed of each of the devices are the same. A data transfer program according to any one of claims 13 to 15,
Storing information on the capacity and usage status of a temporary server for storing data in the data server in a storage area management table;
A data transfer program further comprising the step of storing the data in the data server in the temporary server according to the storage area management table. A data transfer program according to any one of claims 13 to 16, comprising:
Calculating the data movement order when moving the data in the data server to another location;
A data transfer program further comprising the step of moving data in accordance with the data movement order.

Images