JP2004046874A - Data transmitting device and method, data receiving device and method and data distributing system and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize disclosure of data to many users without using a server system and improvement of data reliability. <P>SOLUTION: "Data ALL" on a PC 11 is divided into three data of data 1/3, data 2/3 and data 3/3. Connection is randomly tried to PC's connected to a network from PC ll and the divided data is transmitted to the PC's on which a corresponding system is in operation respectively. The destination of the divided data, PC 21, for example, copies the transmitted data to another PC, PC 22, for example in the same way. The original data is divided and transmitted to other PC's on a network. The divided data is copied and transmitted to still another PC. The original data is distributed on a network, multiplexed and kept, from which data reliability and improvement in access response are expected. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a data transmitting apparatus and method, a data receiving apparatus and method, and a data distribution system that divides data and distributes and holds the divided data in a group of computer apparatuses connected to each other via a network. About the method.

In recent years, network environments have become widespread worldwide, and server systems are being provided everywhere on the network. The server system enables efficient operation of the network by intensively processing various tasks generated on the network. In addition, data that should be disclosed or shared by many users, or important data that has a great effect if lost, is stored in a fault-tolerant server system using a technique such as clustering, which is a dual server technique. Was common.

However, such a fault-tolerant server system generally has a problem that an OS (Operating System) and hardware are very expensive and difficult to manage.

Also, disk storage for retaining data must be multiplexed and operated by a technology such as RAID (Redundant Array of Independent Disks) that performs redundancy using a disk array device in preparation for a failure. Therefore, there is a problem that the disk storage becomes very expensive.

On the other hand, a client, which is a computer device connected to a network and provided with a service from a server system, can acquire data stored on the server by connecting to the server via the network. Via a connected server, data can also be obtained via the network from yet another server which is also connected to the network.

When the number of accesses to the server system increases, the response to the access from the client deteriorates due to an increase in the load on the network, the limitation of the CPU processing and the I / O transfer speed of the hardware in the server system, and the like. was there.

In this case, it is necessary to take measures for distributing access, such as distributing data by adding servers and improving the processing performance of servers. However, for this purpose, there was a problem that a very expensive investment had to be made.

Therefore, an object of the present invention is to provide a data transmission apparatus and method, a data reception apparatus and method, and a data distribution method that can release data to many users and improve data reliability without using a server system. It is to provide a system and a method.

In order to solve the above-mentioned problem, the present invention provides a data transmission device for transmitting data to a network, wherein each of a data dividing unit for dividing original data, and a divided data obtained by dividing the original data by the data dividing unit. On the other hand, attribute information adding means for adding attribute information consisting of at least information indicating the original data and information indicating the relationship between the original data of the divided data, and attribute information adding means for the information equipment connected to the network. A data transmission unit for transmitting each of the divided data added with the attribute information.

Also, the present invention provides a data transmission method for transmitting data to a network, wherein at least an original data is divided into each of the divided data obtained by dividing the original data in the data dividing step. Attribute information adding step of adding attribute information composed of information indicating data and information indicating the relationship between the original data of the divided data, and attribute information adding step of adding attribute information to information devices connected to the network. A data transmission step of transmitting each of the added divided data.

Also, the present invention provides a data receiving apparatus for receiving divided data obtained by dividing original data transmitted through a network, wherein the data receiving apparatus receives divided data obtained by dividing original data transmitted through a network. Receiving means, storage means for holding the divided data received by the data receiving means, and data for transmitting duplicate divided data obtained by duplicating the divided data received by the data receiving means to an information device connected to the network A data receiving device comprising a transmitting unit.

In addition, the present invention relates to a data receiving method for receiving divided data obtained by dividing original data transmitted over a network, wherein the data receiving method receives divided data obtained by dividing original data transmitted over a network. A receiving step, a step of storing the divided data received in the data receiving step in the storage means, and a copy divided data obtained by duplicating the divided data received in the data receiving step to an information device connected to the network. A data transmission step of transmitting data to the data reception method.

Further, the present invention provides a data distribution system for distributing and holding data on a network by dividing original data and distributing each of the divided data obtained by dividing the original data to a plurality of information devices connected via a network. A data distribution system characterized in that the data is distributed and stored.

Also, the present invention provides a data distribution method for distributing and retaining data on a network, wherein the original data is divided, and each of the divided data obtained by dividing the original data is distributed to a plurality of information devices connected via a network. The data distribution method is characterized in that the data is distributed and stored.

As described above, according to the first and seventh aspects of the present invention, the original data is divided, and for each of the divided data, at least information indicating the original data and information indicating the relationship between the original data of the divided data. The attribute data is added to the information device connected to the network, and the divided data to which the attribute information is added by the attribute information adding means is transmitted to the information device connected to the network. Distributed.

In addition, the invention according to claims 8 and 16 receives and retains the divided data obtained by dividing the original data transmitted through the network, and also generates the duplicate divided data obtained by duplicating the received divided data. Since the data is transmitted to the information equipment connected to the network, the original data is distributed and held on the network.

Further, according to the inventions described in claims 17 and 26, the original data is divided and each of the divided data obtained by dividing the original data is distributed and held in a plurality of information devices connected by a network. Original data is distributed and held in information devices on the network.

According to the present invention, original data is divided and stored in a plurality of computer devices, and a plurality of copies are created for each of the divided data, and the copied divided data is further distributed to a plurality of computer devices. And hold it. Therefore, there is an effect that a large-capacity storage system such as a disk array or a server system becomes unnecessary.

{Circle around (4)} Since the data is distributed and held, an improvement in the reliability of the data can be expected, and there is an effect that a storage system or a server system having fault tolerance such as clustering and RAID becomes unnecessary. When the distributed data is encrypted, confidentiality can be enhanced by making the storage location of the key information for encryption different from the storage location of the divided data.

(4) Since the same divided data is distributed and held in a plurality of computer devices, the same data can be obtained through a plurality of paths. Therefore, even if the communication state of a certain path is poor, the same data can be obtained by communicating with another path or another computer device, and when a certain data is requested, one server system can be accessed. Does not concentrate, and the access response increases.

Hereinafter, an embodiment of the present invention will be described. The present invention divides original data and distributes the divided data to a plurality of computer devices connected to each other by a network. This eliminates the need for a large-scale disk storage or server system and can reduce access response.

(1) A distributed system according to an embodiment of the present invention will be schematically described with reference to FIG. The computer devices PC11, PC12, and PC13 are connected by a communication network 10, and data can be exchanged between the computer devices PC11, PC12, and PC13. In the network 10, communication is performed using, for example, TCP / IP (Transmission Control Protocol / Internet Protocol) as a communication protocol.

The networks 20, 30, 40, 50, and 60 also have the same configuration as the network 10 described above. That is, the computer devices PC21 to 24 are connected to the network 20, the computer devices PC31 to 34 are connected to the network 30, the computer devices PC41 to 44 are connected to the network 40, the computer devices PC51 to 54 are connected to the network 50, and the computer devices PC61 to 64 are connected. They are connected by a network 60, and can communicate with each other in each network.

Furthermore, the networks 10, 20, 30, 40, 50, and 60 are respectively connected by the network 70 and can communicate with each other. Therefore, through the network 70, the computer devices PC11 to PC13, PC21 to PC24, PC31 to PC34,... Connected to the networks 10, 20, 30, 40, 50, and 60 respectively become the entire network 70. Can communicate with each other. Hereinafter, these computer devices PC11 to PC13, PC21 to PC24, PC31 to PC34,... Are described as being assumed to be directly connected to the network 70.

In this example, the network 70 also uses TCP / IP as a communication protocol. Each of the computer devices PC11, PC12, PC13, PC21,... That can communicate with each other via the network 70 has a unique IP address.

The networks 10, 20, 30,..., 70 are capable of high-speed communication, and are connected to the computer devices PC11, PC12, PC13, and PC13 connected to the networks 10, 20, 30,. It is desirable that the PCs 21,... Can always communicate with each other via the networks 10, 20, 30,.

The computer devices PC11, PC12, PC13, PC21, PC22,... Include a CPU (Central Processing Unit), a memory such as a RAM (Random Access Memory) and a ROM (Read Only Memory), and a storage device such as a hard disk drive (HDD). A personal computer having a general configuration including communication means for performing communication via a network can be used. Since the configuration of such a computer device is very well known, a detailed description is omitted.

The data distribution holding function for realizing the data distribution system according to the embodiment of the present invention is provided, for example, as a function of an OS (Operating System) in a computer device. However, the present invention is not limited to this, and this data distribution holding function can be realized by application software running on the OS of each computer device. Further, an algorithm for realizing the data distribution holding function can be realized in hardware. Such OS and application software are respectively mounted on the computer devices PC11, PC12, PC13, PC21,.

The computer devices PC11, PC12, PC13, PC21, PC22,... Are not limited to this example, and electronic game devices having, for example, a CPU, a memory, a communication unit, and an HDD can be applied. Of course, other information devices having a CPU, a memory, a communication unit, and a storage unit (for example, an HDD) may be used, or these various devices may be mixed on the network 70. In the above description, the protocol used in each of the networks 10, 20, 30,..., 70 is TCP / IP, but this is not limited to this example.

In such a configuration, for example, it is considered that data “data ALL” stored in the HDD of the computer device PC11 connected to the network 10 is disclosed to other computer devices connected to each other via the network 70. . The data “data ALL” has a data size of 120 MB (megabytes).

When data is disclosed via a network, (1) free disclosure to all computer devices communicable via the network 70, and (2) fee-based access to all computer devices communicable via the network 70. There are three options: public, (3) non-public, that is, the data can be used only by the computer device that holds the data. Hereinafter, the case (1) in which the free publication is selected will be described with reference to the flowchart of FIG.

First, the user stores, on the computer PC11, data "data ALL" to be disclosed via the network 70 in a transmission directory (folder) provided for disclosing data on the HDD of the computer PC11 itself. (Step S10). Hereinafter, this transmission directory is referred to as a “data disclosure directory”. After the user stores the public data in the data public directory, the data distributed holding process according to the embodiment of the present invention is performed in the computer device PC11 by, for example, a background process of an OS (Operating System). Since the processing is performed as background processing by the OS, there is no need for the user to be conscious.

In the next step S11, the data "data ALL" stored in the data disclosure directory is first divided into a plurality of data. The number of divisions can be determined based on the designation of the user. For example, the user specifies the number n of the data “data ALL” to be divided for the computer device PC11. It is also possible to specify the size of the data after division. Here, it is assumed that the data “data ALL” is divided into three pieces of data each having a size of 50 MB, 50 MB, and 20 MB. In addition, each of the divided data is referred to as “data 1/3”, “data 2/3”, and “data 3/3”.

If the user does not specify, the OS automatically determines the number of divisions. At this time, it is more preferable that the OS consider the data size of the data to be divided, the load on the network to which the computer device PC11 is connected, and the like.

(4) In step S11, attribute information of the divided data is added to each of the divided data as predetermined header information. The items of the header information include, for example, (1) the file name of the original file, (2) the size of the original file, (3) the creator of the original file, (4) the registration date and time of the original file, and (5) the OS information of the original file. , (6) total number of divisions, (7) index number of this data, (8) size of this data, (9) number of permitted parent and child, (10) permission of division of child data, (11) system coefficient, and (12) disclosure Classification, (13) password of original data, and the like can be considered.

(4) Each item of the header information will be described by taking as an example the first data “data 1/3” obtained by dividing the data “data ALL”. The original file name of (1) indicates the file name of the original file, that is, the file name of the data “data ALL” which is the original data of the data “data 1/3”. In this example, it is “data ALL”. In the size of the original file of (2), the data size of the original data “data ALL” is indicated by the number of bytes. In this example, it is “120 MB”. The creator of (3) is the name of the copyright holder of the original file, and is determined from data in the OS that is input and registered, for example, when the OS is installed on the computer device PC11.

The registration date and time of (4) indicates the date and time when the original file was disclosed, for example, the date and time information when the data "DATA ALL" was stored in the directory "Data disclosure directory". The OS information of (5) stores, for example, other information on the original file, such as basic information of the OS that has performed the opening process of the file and time correction information.

The total number of divisions of (6) indicates the number n of original files divided. In this example, it is "3". The index number in (7) indicates the order of the data among the data obtained by dividing the original file. In this example, it is “1”. In the data size of (8), the size of the data is indicated by, for example, the number of bytes. In this example, it is “50 MB”.

As will be described later, in the distributed system according to this embodiment, after the divided data is copied to another computer device via the network, the divided data is further transferred to another computer device in the copy destination computer device. Can be copied. At this time, the divided data is referred to as a “parent”, and data obtained by copying the parent data to another computer device is referred to as a “child”. The parent-child permission count of (9) indicates how many times the same divided data is permitted to be copied. In this example, “2” is set, and two child data can be created for one parent data. The child data can be further divided. The permission for division of child data in (10) indicates whether the copied child data can be further divided and copied to another computer device. In this example, “NO” is set, and further division of the child data is prohibited. The system coefficient of (11) indicates the number of times the data is data compared to the original data. In this example, it is "0".

In the public division of (12), for the original data of the data, for example, a flag indicates whether the data is “publicly disclosed for free”, “publicly for paid” or “non-publicly disclosed”. The password of (13) indicates a password used for restoring the original data when, for example, the disclosure category of (12) is “paid publication” or “non-public”. Based on this password information, a user (copyright holder) for the original data of the data can be determined. In this example in which the release category is “free release”, no password is specified.

ヘ ッ ダ A header including such header information is added to each of the divided data. At this time, the OS encrypts a part of the header information and the data body by a predetermined method. All of the header information may be encrypted.

(4) The encryption of the header information and the data can be made different depending on the value of the “public category”. For example, if the “public category” is set to “free publication”, a default encryption that can be automatically decrypted by the OS is performed, and if the “public category” is “paid public”, a predetermined It can be encrypted so that it cannot be decrypted without entering a password.

(4) When data division and header addition are performed in step S11, the process proceeds to the next step S12. In step S12, the transmission preparation of the first data among the n pieces of data obtained by dividing the original data is performed. That is, the transmission of the data (in this example, the data “data 1/3”) in which the index number of (7) in the above-described header information is “1” is prepared. Transmission processing.

First, in step S13, an IP address is randomly selected by the computer device PC11, and an attempt is made to access another computer device communicably connected via the network 70. As a result, it is checked whether or not the connection destination computer connected based on the IP address can access the port of the port number (TCP port number) corresponding to the function.

選 択 The selection of the IP address in step S13 is not limited to random. For example, the computer device PC11 may have a list of IP addresses indicating computer devices to which the computer device PC11 can connect in advance, for example, as a table on the HDD. At the time of connection, this table is referred to and connection is attempted sequentially. In this case, the list does not need to list the IP addresses of all the computer devices that can be connected via the network 70.

When the connection based on the IP address and the TCP port number is confirmed, in the next step S14, it is determined whether or not the function, that is, the distributed system according to the embodiment is operating on the OS of the connection destination computer device. Can be examined. If it is determined that the function is not operating in the connection destination computer apparatus PC, the process returns to step S13, and an attempt is made to access another IP address.

On the other hand, if it is determined in step S14 that the function is operating on the OS of the connection destination computer device, the process proceeds to step S15. Here, it is assumed that the computer device PC21 is a connection destination computer device. In a computer device corresponding to the function, a directory for receiving the transmitted data (hereinafter referred to as a data reception directory) is provided on the HDD in advance. In step S15, the transmission of the data “Data 1/3” as the first divided data is started from the computer device PC11 to the data receiving directory on the computer device PC21 to which the computer device PC11 is connected.

(4) The transmission state of data is exchanged between the transmission-side computer apparatus PC11 and the reception-side computer apparatus PC21, for example, by handshake, and it is confirmed whether the data transmission has been completed (step S16). If any error occurs during data transmission and data transmission cannot be completed, the process returns to step S13.

{Circle around (2)} The divided data confirmed to be transmitted in step S16 is given a file name in the receiving computer device PC21 and is held in the data receiving directory. Since the content of the transmission data can be determined from the header attached to the data, an arbitrary file name can be used as the file name of the received data in the data reception directory.

Here, it is desirable to prepare a relative table of data names and IP addresses for all OSs. When the data is transmitted, it is described in the table, so that the search time can be reduced when executing the data search described later. For example, data such as “Data 1/3 exists on the computer device PC21 of the IP address xx.xxx.xxx.xx” is added to the relative table of the data name and the IP address on the computer device PC11 on the transmission side. Keep it. Further, each time the computer device PC11 is connected to another computer device, the relative time table of the data name and the IP address is exchanged between the connection destination computer device and the connection source computer device, thereby further shortening the search time. Can be.

(4) If it is determined in step S16 that the data transmission has been completed, it is checked whether or not untransmitted data still exists among the divided data in the data disclosure directory of the computer device PC11 on the transmission side. If it is determined that all of the divided data has been transmitted and that there is no untransmitted data, the process proceeds to step S19, and a series of processes ends. At this time, the data "data ALL" stored for disclosure in the data disclosure directory of the computer device PC11 on the transmission side can be deleted.

On the other hand, if it is determined in step S16 that there is untransmitted data, the process proceeds to step S18 to prepare for transmission of the next data. Then, the process returns to step S13, another computer device capable of transmitting data is searched for from the computer devices connected to the network 70, and the data is transmitted to the computer device.

In the example of FIG. 1, among the data obtained by dividing the data "Data ALL" on the computer device PC11, "Data 1/3" is transmitted to the computer device PC21 as described above, and "Data 2/3" is transmitted. The computer device PC23 and “data 3/3” are transmitted to the computer device PC42. It is preferable to control so that each of the divided data is transmitted to different computer devices.

Also, if the original data is divided in such a manner that the original data of the original data cannot be identified from each of the divided data obtained by dividing the original data, the contents of the original data are transmitted to the computer device to which the divided data is transmitted. It can be concealed and is more preferable.

Furthermore, by configuring each of the divided data so that the original data cannot be identified, it may be possible to avoid the application of the copyright regulation to each of the divided data. That is, for example, when the original data is copyright-protected moving image data, if the original data is simply divided along the time axis corresponding to the reproduction of the moving image data to generate the divided data, each of the divided data becomes a moving image. Because it is reproducible, when it is transmitted to another computer device, it may be considered that the copyright law is violated. It is conceivable that application of such a copyright law can be avoided if the content of moving image data cannot be recognized by the divided data alone.

Various methods of dividing the data so that the original data cannot be identified from each of the divided data can be considered. For example, it is conceivable that the entire original data is encrypted by a predetermined encryption method, and the encrypted data is divided to generate divided data. However, the present invention is not limited to this, and the original data can be divided so as to be divided in a bit permutation. For example, the original data is divided for each byte so as to be divided into a most significant bit, a least significant bit, bits between them, and the like, thereby generating divided data. Furthermore, data may be extracted from the original data in fine units at arbitrary intervals, and the data in the fine units thus extracted may be combined based on a predetermined rule to generate divided data. Of course, these methods can be combined to generate divided data, and further another method can be used.

Next, a case where the received divided data is copied to another computer in the computer device that has received the divided data will be described with reference to the flowchart in FIG. When the received divided data is copied to another computer device, the copied data is made child data with respect to the original data that is the parent data.

Here, the computer apparatus PC21 to which the divided data “data 1/3” is transmitted from the computer apparatus PC11 according to the above-described flowchart of FIG. 2 will be described as an example. Further, the processing on the computer device PC21 described below is automatically executed in the background by the OS of the computer device PC21.

(4) When the data “data 1/3” is transmitted from the computer device PC11 in step S20, the data “data 1/3” is received in step S21 in the transmission destination computer device PC21. The received data "data 1/3" is stored in a data receiving directory provided in advance on the HDD of the computer device PC21 (step S21). When the data reception is completed, the computer device PC21 reads the header information from the header of the received data “data 1/3”.

(4) In the read header information, it is determined in step S22 whether or not the number of data copies exceeds the number of times indicated in the parent-child permission count based on the parent-child permission count described in (9) above. For example, each time the received divided data is copied to another computer device, if the number of permitted parent and child times is reduced by 1 to rewrite the header, the data is transmitted to another computer device when the number of permitted parent and child times is 1 or more. It is necessary to copy, and it can be determined that there is no need to copy when the parent-child permission count is 0.

(5) If it is determined that the number of data copies exceeds the number indicated in the parent-child permitted number, a series of processing is terminated. On the other hand, if the number of copies has not exceeded the number indicated in the parent-child permitted number, the process proceeds to step S23, and the next copy is performed.

In step S23, it is determined whether or not the data is further divided and copied to another computer based on the above-described (10) permission to divide the child data in the read header information. If the child data division permission is a value indicating that the data is further divided, the process proceeds to step S24, and the data is further divided into a predetermined number of divisions. In the division processing at this time, for example, similar to the processing in step S11 in the flowchart of FIG. 2 described above, processing such as data division, generation of header information on each of the divided data, and addition of a header are performed.

と When the data is divided in step S23, the process proceeds to step S25. If it is determined in step S23 that the data is not to be divided, the process proceeds to step S25. In the processing of step S25 and subsequent steps, data is transmitted to another computer device by the same processing as the processing of steps S13 to S18 in the flowchart of FIG. 2 described above.

That is, in step S25, an IP address is selected by the computer device PC21 randomly or by referring to a table, an attempt is made to access another computer device, and a port of a port number corresponding to the function is connected to the connected computer. Is checked to see if it is accessible. In the next step S26, it is checked whether or not the function is operating on the OS of the connection destination computer device. If it is determined that the function is not operating, the process returns to step S25 and another IP address is set. Access is attempted to If it is determined that the function is operating on the OS of the connection destination computer device, the process proceeds to step S27, and the data reception directory of the connection destination computer device (computer device PC22) is set. For example, transmission of data “data 1/3” is started.

(4) The data transmission state is exchanged between the computer device PC21 on the transmitting side and the computer device PC22 on the receiving side by, for example, handshake, and it is confirmed whether the data transmission has been completed (step S28). If any error occurs during data transmission and data transmission cannot be completed, the process returns to step S25.

{Circle around (4)} The divided data confirmed to be transmitted in step S28 is given a file name in the receiving computer PC22 and is held in the data reception directory. Since the content of the transmission data can be determined from the header attached to the data, an arbitrary file name can be used as the file name of the received data in the data reception directory.

If it is determined in step S28 that the data transmission has been completed, it is checked whether or not untransmitted data still exists in the data disclosure directory of the computer device PC21 on the transmission side (step S29). For example, when the data is further divided in step S24, it is checked whether or not the remaining divided data still exists. If it is determined that there is no untransmitted data, a series of processing ends. In this case, the data “data 1/3” used for transmission in the computer device PC21 on the transmission side is not deleted.

On the other hand, if it is determined in step S29 that there is untransmitted data, preparations for transmitting the next data are made, and the process returns to step S25, where another computer capable of transmitting data is connected to network 70 again. Then, the next data is transmitted to the searched computer device.

(4) In this way, a plurality of pieces of the divided data are stored in the computer device connected to the network 70. In the example of FIG. 1, “data 1/3” transmitted to the computer device PC21 is copied to the computer device PC22 and further copied to the PC31. The “data 2/3” transmitted to the computer device PC23 is copied to the computer device PC24 and further copied to the PC43. “Data 3/3” transmitted to the computer device PC42 is copied to the computer device PC51, and further copied to the PC53.

In the above steps S23 and S24, if data division is instructed by child data division permission in the header, as described above, the data obtained by dividing the original data is further divided, and the divided data is The data is transmitted and copied to another computer device, and the data is propagated. For example, the data “data 1/3” obtained by dividing the original data further includes data “data 1 / 3-1 / 3”, “data 1 / 3-2 / 3”, and “data 1 / 3-3 / 3 ". The divided data is transmitted to different computer devices and copied.

As described above, in one embodiment of the present invention, the original data is divided and stored in a plurality of computer devices, and a plurality of copies are created for each of the divided data. Are further distributed and held in a plurality of computer devices. Therefore, a large-capacity storage system such as a disk array or a server system is not required. In addition, since the data is distributed, an improvement in data reliability against a system failure or the like can be expected.

(4) Since the same divided data is distributed and held in a plurality of computer devices, the same data can be obtained through a plurality of paths. Therefore, even if the communication state of a certain path is poor, the same data can be obtained by communicating with another path or another computer device. In other words, when certain data is requested, access is not concentrated on one server device.

Further, as a computer device constituting the distributed system according to the embodiment, for example, when a notebook personal computer that can be driven by a battery power supply is used, the notebook personal computer is a computer device with an uninterruptible device. You can think. Therefore, by using a large number of notebook personal computers as the computer devices constituting the distributed system according to the embodiment, a distributed system that is resistant to an accident such as a power failure can be constructed.

Next, a description will be given of a case where a computer device on which the distributed system according to the embodiment of the present invention is operating is disconnected from the network. The computing device is disconnected from the network when shut down, for example. A computer device disconnected from the network cannot be referred to from other computer devices connected to the network. Therefore, if the divided data transmitted from the other computer device to the computer device exists in a state where copying to another computer device is not performed, the divided data is at least The computer device cannot be taken out until it is connected to the network next time. In order to avoid such a situation, in this embodiment, when the computer device is disconnected from the network, the divided data stored in the computer device is transmitted to another computer device. This transmission process is automatically performed when the network is disconnected, and after the data transmission is completed, the computer device is disconnected from the network.

FIG. 4 is a flowchart showing an example of processing in the computer device when the network is disconnected by the distributed system according to the embodiment. The power supply of the computer device is controlled by the OS, and the shutdown is executed by instructing the OS to shut down. That is, for example, when the user instructs the computer to shut down, the OS automatically performs a series of processes required for shutdown, for example, disconnection from the network, and finally turns off the power of the computer by the OS. And the shutdown is completed.

For example, when the disconnection from the network is instructed by shutdown or the like in the computer device PC53 (step S30), transmission of all data held in the data reception directory provided on the HDD of the computer device PC53 is prepared. (Step S31). Here, it is assumed that “data 3/3” is held in the data reception directory of the computer device PC53.

(4) Thereafter, transmission of data on the data reception directory is started in the same manner as the above-described processing after step S25 in FIG. In step S32, an IP address is selected by the computer device PC53 at random or by referring to a table, an attempt is made to access another computer device, and an access is made to the port of the port number corresponding to the function in the connected computer. The possibility is checked. In the next step S33, it is checked whether or not the function is operating on the OS of the connection destination computer device. If it is determined that the function is not operating, the process returns to step S32, and another IP address is set. Access is attempted to

If it is determined in step S33 that the function is operating on the OS of the connection destination computer device, the process proceeds to step S34, where the data reception directory of the connection destination computer device (computer device PC54) is set. In response to this, transmission of data “data 3/3” held in the data reception directory of the computer device PC53 is started. At the time of data transmission at the time of network disconnection, the permitted number of parent and child in the header information is not rewritten.

(4) The data transmission state is exchanged between the transmission-side computer device PC53 and the reception-side computer device PC54, for example, by handshake, and it is confirmed whether the data transmission has been completed (step S35). If any error occurs during data transmission and data transmission cannot be completed, the process returns to step S32.

If it is determined in step S35 that the data transmission has been completed, it is checked whether or not untransmitted data still exists in the data reception directory of the computer device PC53 on the transmission side (step S36). If it is determined that there is no untransmitted data, a series of data transmission processing is terminated, and another process of shutdown is executed in the computer device PC53. When the data transmission process is completed, the transmitted data can be deleted from the data reception directory of the computer device PC53.

On the other hand, if it is determined in step S36 that there is untransmitted data, the next data is prepared for transmission, the process returns to step S32, and another computer capable of transmitting data is connected to the network 70 again. Then, the next data is transmitted to the searched computer device.

Next, a method for acquiring data published on the network 70 as described above will be described. Here, a case where data “data ALL” is obtained from the computer device PC61 is considered. For example, when the user instructs the computer device PC61 to acquire the data "data ALL", first, the computer device PC61, for example, a computer device that is close to the network (computer device PC53 in this example). ), The data (data ALL) obtained by dividing the data “data ALL” in the data receiving directory of the computer device PC53 (in this example, the data “data 1/3”, “data 2/3” or “data 3/3”). ) Is checked for existence.

If it is determined that the data obtained by dividing the data “data ALL” does not exist on the computer device PC53, the other computer devices connected to the network 70 are sequentially accessed by the computer device PC61, and the data reception directory is obtained. It is checked whether or not the data exists.

As described above, a file name of the data obtained by dividing the data “DATA ALL” is arbitrarily set when the data is stored in the data receiving directory in the transmission destination computer device. Therefore, the data search here is performed by referring to the file name of the original data included in the header information of each data. When data is searched using the file name of the header information, another file having the same file name may be obtained as a search result. In such a case, other items of the header information, for example, “author of the original file”, “date and time of registration of the original file”, “OS information of the original file”, and the like can also be used as search conditions.

Note that it is preferable that the computer device PC61 can acquire the above-mentioned relative table of the data name and the IP address from the connection destination computer device, because the computer device having the data can be searched more quickly.

In this way, when a computer device (here, the computer device PC51, in which the data 3/3 is searched) in which the data obtained by dividing the data "Data ALL" is stored is found, the computer device PC61 and the computer PC61 are connected. The device PC51 is connected, and the computer device PC61 requests the computer device PC51 to transmit the data “Data 3/3” to the computer device PC61. In response to this request, the data “Data 3/3” is transmitted from the computer device PC51 to the computer device PC61. The transmitted data “data 3/3” is received by the computer device PC61 and stored in a predetermined directory.

(4) The computer device PC61 checks the “total number of divisions” in the header information of the received data “data 3/3”. Accordingly, it is possible to determine how many pieces of remaining data need to be acquired in order to restore the original data of the data “data 3/3”. Based on this determination result, the above-described procedure is repeated to obtain the remaining data.

(4) When all the divided data for restoring the original data are thus obtained, the data can be restored and combined. Here, if the original data of the divided data is set to be freely available for free based on the “disclosure section” of the header information, the divided data is restored and combined as it is to obtain data “data ALL” as the original data. be able to.

For example, if the above-described default encryption is performed on each of the divided data that has been made free of charge, the encryption of each divided data is automatically decrypted by the OS in the computer device PC61. Then, the header of each divided data is removed, and each divided data is sequentially combined based on the index number of each divided data.

Each divided data may be encrypted with a randomly generated key, for example, DES (Data Encryption Standard). In this case, the key is stored in a different location, ie, a different computer device, from the divided and encrypted data. For example, a relative table is created between the data name, the IP address of the storage destination of the data, and the IP address of the storage destination of the encryption key, so that the storage destination of the key can be known. This makes it impossible to read the contents of the divided data by a single computer device that owns the divided data, thereby increasing the confidentiality of the data.

On the other hand, if the “public category” is set to paid publication, the data can be restored and combined after charging by a predetermined method. There are several charging methods.

方法 As an example, a method using a password can be considered. In this case, when restoring and combining the divided data, the OS prompts for a password. The user inputs a credit card number in advance on a site on the network operated by the copyright holder of the original data of the divided data, and has a password issued. By inputting this password to the OS, restoration and combination of the divided data are performed.

As another example, a method using a setup program for restoring data can be considered. In this case, when the transmission source computer device divides the original data stored in the data public directory and transmits the data to each computer device, the original data is temporarily converted into a setup program, and the setup program is divided. When the original data is restored, first, the divided data is automatically restored and combined by the OS, and the setup program is restored. Then, a predetermined host computer on the network is accessed by the setup program, and the host computer performs a billing process. After the charging process, a setup process is performed by a setup program, and the original data is restored.

デ ー タ As described above, it is also possible to set data to be private by the “public classification”. In this case, as an example, when searching for data, processing must be performed on the OS so that the data cannot be obtained as a search result unless a password that can be known only by the copyright holder of the data is input along with the data name. There is a way to do it.

For example, if the “public category” of the data stored in the data public directory is set to “non-public”, a password is also entered and included in header information and the like. When searching for data, a password is input in advance along with the data name. When the “public classification” of the header information of the data retrieved by the data name is “non-public”, if the password included in the header information does not match the password input in advance at the time of retrieval, the data is Prevent search results.

Also, as another example, it is possible to search and acquire data, but a method of requesting the input of a password when restoring and combining the data is conceivable. Also in this case, as described above, when the “public classification” of the data stored in the data public directory is set to “non-public”, the password is also input and included in the header information and the like. Then, if the “public classification” of the header information is set to “non-public” in the data obtained as a result of the search, processing is performed on the OS so as to prompt the input of the password. If the input password does not match the password included in the header information of the acquired data, the data cannot be restored and combined.

1 is a schematic diagram schematically showing a distributed system according to an embodiment of the present invention. 5 is a flowchart illustrating an example of processing when data is disclosed via a network according to an embodiment of the present invention. 11 is a flowchart illustrating an example of a process when copying received divided data to another computer device. 5 is a flowchart illustrating an example of processing in the computer device when the network is disconnected by the distributed system according to the embodiment.

Explanation of reference numerals

10, 20, 30, 40, 50, 60, 70 ... network, PC11, PC12, PC13, PC21, PC22, PC23, PC24, PC31, PC32, PC33, PC34, PC41, PC42, PC43, PC44, PC51, PC52, PC53, PC54, PC61, PC62, PC63, PC64 ... Computer device

Claims (29)

In a data transmission device for transmitting data to a network,
Data dividing means for dividing the original data;
Attribute information for adding attribute information including at least information indicating the original data and information indicating a relationship between the divided data and the original data to each of the divided data obtained by dividing the original data by the data dividing unit; Additional means;
A data transmission unit for transmitting each of the divided data to which the attribute information has been added by the attribute information addition unit to an information device connected to a network. The data transmission device according to claim 1,
Further comprising storage means for storing data;
The division of the original data by the data dividing unit, the addition of the attribute information to each of the divided data by the attribute information adding unit, and the transmission of the divided data by the data transmitting unit are performed in a predetermined area of the storage unit. A data transmission device, wherein the data transmission is automatically performed on the stored original data. The data transmission device according to claim 1,
The data transmission device, wherein the information indicating the original data includes at least a name, a data size, and a registration date and time of the original data. The data transmission device according to claim 1,
The information indicating the relationship between the divided data and the original data includes at least the number of the divided data divided from the original data and the position on the original data of the divided data to which the attribute information is added. A data transmission device characterized by the above-mentioned. The data transmission device according to claim 1,
The data transmitting means randomly specifies the information device connected to the network and attempts communication, and checks whether or not the specified information device can perform predetermined processing on the divided data. And transmitting the divided data to the information device if the designated information device is capable of performing the predetermined processing on the divided data. The data transmission device according to claim 1,
The data transmission method further comprises a table indicating a correspondence between information indicating the divided data transmitted by the data transmission means and information indicating a transmission destination of the divided data transmitted by the data transmission means. apparatus. The data transmission device according to claim 1,
The data transmission device, wherein the data dividing means divides the original data so that the content of the original data cannot be identified from each of the divided data obtained by dividing the original data. In a data transmission method for transmitting data to a network,
A data dividing step for dividing the original data;
An attribute for adding attribute information consisting of at least information indicating the original data and information indicating a relationship between the divided data and the original data to each of the divided data obtained by dividing the original data in the data dividing step A step of adding information;
Transmitting the divided data to which the attribute information has been added in the attribute information adding step to the information device connected to the network. In a data receiving device that receives divided data obtained by dividing original data transmitted through a network,
Data receiving means for receiving the divided data obtained by dividing the original data transmitted through the network,
Storage means for holding the divided data received by the data receiving means,
A data receiving device, comprising: data transmitting means for transmitting, to an information device connected to a network, duplicate divided data obtained by duplicating the divided data received by the data receiving means. The data receiving apparatus according to claim 9,
The transmission of the duplicate divided data by the data transmitting means is performed based on copy permission information that is supplied in addition to the divided data and that indicates the number of times that the divided data is duplicated. apparatus. The data receiving apparatus according to claim 9,
The data receiving apparatus, wherein the receiving of the divided data by the receiving means and the transmission of the duplicate divided data by the data transmitting means are automatically performed. The data receiving apparatus according to claim 9,
Data dividing means for further dividing the divided data received by the receiving means, wherein each of the data divided by the data dividing means is transmitted to an information device connected to a network by the data transmitting means. A data receiving apparatus characterized in that: The data receiving apparatus according to claim 9,
The data transmitting means randomly specifies the information device connected to the network and attempts communication, and checks whether or not the specified information device can perform predetermined processing on the divided data. And transmitting the duplicated divided data to the information device if the designated information device is capable of performing the predetermined processing on the divided data. The data receiving apparatus according to claim 9,
A data receiving apparatus, wherein when the communication with the network is cut off, the divided data stored in the storage means is transmitted to the information device connected to the network. The data receiving apparatus according to claim 9,
It further comprises a table showing a correspondence relationship between the information indicating the duplicate divided data transmitted by the data transmitting means and the information indicating the transmission destination of the duplicate divided data transmitted by the data transmitting means. Data receiver. The data receiving apparatus according to claim 9,
A data receiving apparatus, wherein the divided data is divided so that the contents of the original data from which the divided data is divided cannot be identified from each of the divided data. In a data receiving method for receiving divided data obtained by dividing original data transmitted through a network,
A data receiving step of receiving the divided data obtained by dividing the original data transmitted through the network;
Holding the divided data received in the data receiving step in storage means,
Transmitting a duplicate divided data obtained by duplicating the divided data received in the data receiving step to an information device connected to a network. In a data distribution system that distributes and holds data on a network,
A data distribution system, wherein original data is divided, and each of the divided data obtained by dividing the original data is distributed and stored in a plurality of information devices connected via a network. The data distribution system according to claim 18,
A data distribution system wherein attribute information including at least information indicating the original data and information indicating a relationship between the divided data and the original data is added to each of the divided data. The data distribution system according to claim 19,
A data distribution system, wherein the information indicating the original data includes at least a name, a data size, and a registration date and time of the original data. The data distribution system according to claim 19,
The information indicating the relationship between the divided data and the original data includes at least the number of the divided data divided from the original data and the position on the original data of the divided data to which the attribute information is added. A data distribution system, characterized in that: The data distribution system according to claim 18,
The information devices connected to the network are specified at random, and the divided data is distributed to the information devices which are determined to be capable of performing predetermined processing on the distributed data among the specified information devices. A data distribution system, characterized in that the data distribution system is configured to cause the data to be distributed. The data distribution system according to claim 18,
A data distribution system, further comprising a table indicating a correspondence relationship between information indicating the distributed divided data and information indicating a distribution destination of the divided data. The data distribution system according to claim 18,
2. The data distribution system according to claim 1, wherein the divided data held in the information device is duplicated and held in another information device. The data distribution system according to claim 18,
2. The data distribution system according to claim 1, wherein the divided data stored in the information device is further divided and distributed and stored in a plurality of other information devices. The data distribution system according to claim 18,
The data distribution system according to claim 1, wherein when the information device is disconnected from the network, the stored divided data is stored in another information device connected to the network. The data distribution system according to claim 18,
A data distribution system, wherein the divided data is divided so that the contents of the original data from which the divided data is divided cannot be identified from each of the divided data. In a data distribution method for distributing and retaining data on a network,
A data distribution method, wherein original data is divided, and each of the divided data obtained by dividing the original data is distributed and stored in a plurality of information devices connected via a network. The data distribution method according to claim 28,
The divided data is encrypted using key information,
A data distribution method, wherein the key information is held in an information device different from the plurality of information devices holding the divided data.

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