JP4383826B2 - Device-to-device data exchange system, device used therefor, exchange completion data management device and program - Google Patents

Description

  The present invention relates to a system for exchanging electronic data owned by each other between devices, and more particularly to a system that can complete the processing fairly for both devices performing the exchange processing.

  In recent years, with the spread of high-speed networks such as ADSL (Asymmetric Digital Subscriber Line) and FTTH (Fiber To The Home), P2P (Peer To Peer) that exchanges electronic data owned by each other between devices. ) Type data exchange system has appeared.

  The P2P type system that first appeared was a pure P2P type data exchange system composed of only two devices. For example, WinMX corresponds to this. In a pure P2P type data exchange system, 1) a function for requesting the other device to transmit the data desired by itself, 2) a function for transmitting the data requested by the other device, and 3) data from the other device. 4) Only a function of interrupting data transmission to the counterpart device. Thereby, data can be transmitted and received with each other. However, since the exchanged data sizes are different or the data transmission / reception speeds of the two are different, it is possible that one device completes data reception earlier than the other device. Therefore, in a pure P2P type data exchange system, by stopping the data transmission to the other party when you have completed the reception of the data, There was an unfair act of not completing the data reception.

Therefore, as a means for preventing the unfair acts described above, a method of providing a server in charge of data exchange processing has been proposed (see, for example, Patent Document 1 and Non-Patent Document 1). . In such a P2P type data exchange system with an intermediary server, in order to cope with a situation in which some problem occurs during data exchange between devices and the device cannot acquire the target data, First, the data to be exchanged is uploaded to the mediation server. In the P2P type data exchange system with an intermediary server, the intermediary server holds the data to be exchanged even if only one terminal cannot acquire the target data during data exchange between devices. The device that could not acquire the data can receive data supplement from the mediation server.
US Pat. No. 6,061,792 N. Asokan, Victor Shue, Michael Wayne Donner (N. Asokan, Victor Shoup and Michael Waidner), Asynchronous Protocols for Optomicistic Fair Exchange (“Asynchronous Protocol 30 RZ 76, Optimal Research for 29”) Report RZ 2976 (# 93022)), IBM Research, December 1997.

  When a pure P2P type data exchange system such as WinMx is used, the following problems occur. If an illegal act as described above is performed during data exchange between devices, the user of one device wants to cancel the data exchange. For example, when the device A and the device B are exchanging data, the device A acquires the target data before the device B and disconnects the communication with the device B. The user feels dissatisfied that he / she could not acquire data from the device A, and wants to cancel the data exchange with the device A and stop the data exchange. However, in such a situation, the device B cannot use or retrieve the data that has been passed to the device A. Thus, in the conventional pure P2P type data exchange system, when the other device has already completed data acquisition, the data exchange decided to be performed once cannot be canceled halfway. Therefore, even if an unfair exchange is performed, a situation occurs in which only one obtains and obtains data, and the other obtains and loses data.

  In the P2P type data exchange system with an intermediary server, after the data is uploaded to the intermediary server, data is exchanged between both terminals, and the data of the intermediary server is transmitted to one terminal when communication fails. Therefore, both terminals can always acquire data. However, since data to be exchanged between devices must first be uploaded to the mediation server, the communication cost and the load on the mediation server increase in proportion to the amount of data.

  Therefore, an object of the present invention is to provide an inter-device data exchange system that prevents unfair exchanges without increasing communication costs and server burdens, and a terminal, server, and program used therefor. is there.

  In order to solve the above problems, the present invention has the following features. A first aspect of the present invention is a system for exchanging data between devices connected via a communication medium, and possesses at least one exchangeable data, and is exchanged with other devices. Connected to the first device and the second device via the communication medium, the first device that desires data exchange with the first device, the second device that owns the data desired by the first device, and the first device. After the second device completes the data exchange, the first exchange completion data, which is data necessary for reproducing the data acquired by the first device, and the data acquired by the second device are reproduced. And an exchange completion data management device for managing the second exchange completion data, which is necessary data for the exchange, and the exchange completion data management device allows both the first and second devices to normally receive desired data. The first replacement completion Sends data to the first device, including the exchange completion data transmission means for transmitting a second exchange completion data to the second device.

  Preferably, the first device exchanges first exchange completion data creating means for creating second exchange completion data, and second exchange completion data created by the first exchange completion data creating means. A second exchange completion data creating means for creating the first exchange completion data; and a second exchange completion data creating means for creating the first exchange completion data. Second exchange completion data transmission means for transmitting the created first exchange completion data to the exchange completion data management apparatus, and the exchange completion data management apparatus further includes the first exchange completion data transmission means transmitted from the exchange completion data transmission means. In addition, it is preferable to include exchange completion data management means for managing the second exchange completion data so that the transmission source device can be identified.

  In addition, the first device further includes a first data conversion unit that converts data owned by the device into data that can be normally reproduced only by using the second exchange completion data; First data restoring means for restoring the data received from the first device to data that can be normally reproduced using the first exchange completion data, and the second device is further owned by the first device. Second data conversion means for converting the data to be converted into data that can be normally reproduced for the first time by using the first exchange completion data, and the data received from the first device as the second exchange completion data. And a second data restoring means for restoring to data that can be normally reproduced.

  Preferably, the first device further includes first exchange completion data creation request means for requesting the exchange completion data management apparatus to create second exchange completion data, and the second device further includes: And a second exchange completion data creation requesting means for requesting the exchange completion data management device to create the first exchange completion data. The exchange completion data management device further includes the first and second exchange completions. In response to a request from the data creation requesting means, the exchange completion data creating means for creating the first and second exchange completion data, and the first and second exchange completion data created by the exchange completion data creating means are requested. It is preferable to include exchange completion data management means for managing so that the previous device can be identified.

  Each of the first and second devices further converts the first data owned by the own device into second data that can be normally reproduced only by using the exchange completion data. And data restoration means for restoring the data received from the data exchange partner device to data that can be normally reproduced using the exchange completion data transmitted from the exchange completion data sending means. The completion data management apparatus uses the first and second exchange completion data to convert the first and second conversion processing data for converting the first data so that the second data can be normally reproduced. Further comprising conversion processing data creation and transmission means for generating and transmitting the first conversion processing data to the second device and transmitting the second conversion processing data to the first device; The data conversion unit of the first device converts the first data into the second data using the second conversion processing data from the conversion processing data transmission unit, and the data conversion unit of the second device converts the first data The first data may be converted into the second data using the first conversion processing data from the processing data transmission means.

  For example, the first conversion process data is a first encryption key, the first exchange completion data is a first decryption key corresponding to the first encryption key, and the second exchange process data is The second encryption key and the second exchange completion data may be a second decryption key corresponding to the second encryption key.

  Preferably, each of the first and second devices further includes communication result notification means for notifying the exchange completion data management device of information indicating a communication result when communication with the data exchange partner device is completed. The exchange completion data transmitting means determines whether or not both the first and second devices have successfully received the desired data based on the information indicating the communication result from the communication result notifying means of the first and second devices. It is good to judge.

  Preferably, the information indicating the communication result is information indicating whether or not the desired data has been normally received, and the information indicating that the exchange completion data transmitting unit has normally received from the first and second devices. The exchange completion data may be transmitted when the message is received.

  For example, the first exchange completion data is a decryption key for decrypting the data given to the first device by the second device, and the second exchange completion data is the second key for the first device. It may be a decryption key for decrypting data given to the device.

  Preferably, the first device and the second device may further include retransmission request means for requesting retransmission of data to the exchange partner device when the desired data cannot be completely received.

  A second aspect of the present invention is a device for exchanging desired data and data owned by the own device with another device that owns the desired data, and reproducing the data owned by the own device. Exchange completion data creation means for creating first exchange completion data, which is data necessary for the exchange, and exchange completion data management for managing the exchange completion data for the first exchange completion data created by the exchange completion data creation means When communication between the exchange completion data registration means to be registered in the apparatus and another device is completed, the second exchange completion data, which is data necessary for reproducing the data acquired from the other device, is exchanged data management. Replacement completion data acquisition means acquired from the apparatus.

  Preferably, the data possessed by the device itself is further converted into data that can be normally reproduced only by using the first exchange completion data, and the second data obtained by the exchange completion data obtaining means. It is preferable to include data restoration means for restoring data acquired from another device to data that can be normally reproduced using the exchange completion data.

  Furthermore, the data conversion means further comprises an exchange history storage means for storing a past exchange history with the data exchange partner device, the data conversion means changes the data conversion method based on the exchange history, and the exchange completion data creation means Based on the exchange history, the exchange completion data creation method may be changed.

  Furthermore, it is preferable to include a retransmission request means for requesting retransmission of data to the exchange partner device when the desired data cannot be completely received.

  A third aspect of the present invention is a device for exchanging desired data and data owned by the own device with another device that owns the desired data, and reproducing the data owned by the own device. When the communication between the exchange completion data creation requesting means for requesting the exchange completion data management device for managing the exchange completion data and the creation of the first exchange completion data, which is data necessary for performing, is completed, Replacement completion data acquisition means for acquiring second replacement completion data, which is data necessary for reproducing data acquired from another device, from the replacement completion data management device.

  Preferably, a conversion process for converting the owned data so that the data owned by the own device can be normally reproduced by using the first exchange completed data sent from the exchange completed data management device. Conversion processing data receiving means for receiving data, data conversion means for converting data owned by the own device using the conversion processing data received by the conversion processing data receiving means, and second data acquired by the exchange completion data acquiring means It is preferable to include data restoration means for restoring data acquired from another device to data that can be normally reproduced using the exchange completion data.

  Further, an exchange history storage means for storing a past exchange history with the data exchange partner device, and a conversion method notification means for notifying the exchange completion data management apparatus of a conversion method used in the data conversion means based on the exchange history. The data conversion means may convert the data owned by the own device using the conversion processing data using the designated conversion method sent from the exchange completion data management device.

  Furthermore, it is preferable to include a retransmission request means for requesting retransmission of data to the exchange partner device when the desired data cannot be completely received.

  4th aspect of this invention is the exchange completion data management apparatus used with the system for exchanging data between the apparatuses connected via a communication medium, Comprising: Between 1st apparatus and 2nd apparatus Only when the exchange completion data management means for managing exchange completion data necessary for reproducing the data exchanged between the first and second devices can successfully receive the desired data. The exchange completion data necessary for reproducing the data acquired by the second device is transmitted to the first device, and the exchange completion data necessary for reproducing the data acquired by the second device is transmitted to the second device. Exchange completion data transmission means.

  Preferably, in addition, in response to requests from the first and second devices, the exchange completion data creating means for creating the exchange completion data, and the exchange destination data created by the exchange completion data creating means is received by the request destination device. It is preferable to include an exchange completion data management means that manages the identification data so that it can be identified.

  Furthermore, the conversion completion data for enabling the first and second devices to normally reproduce the exchanged data using the exchange completion data created by the exchange completion data creation means is created, It is preferable to include conversion processing data creation / transmission means for transmitting to the first and second devices.

  Preferably, the exchange completion data transmission means determines whether or not both the first and second devices have successfully received the desired data based on information indicating communication results from the first and second devices. It is good to judge.

  For example, the information indicating the communication result is information indicating whether or not the desired data has been normally received, and the exchange completion data transmitting means receives information indicating that the data has been normally received from the first and second devices. If received, exchange completion data may be transmitted.

  Preferably, it further includes an exchange completion data deleting means for deleting the managed exchange completion data when a predetermined condition is satisfied.

  For example, if the exchange completion data transmitted by the exchange completion data transmitting unit is normally received by the first and second devices as the predetermined condition, the exchange completion data deleting unit sends the first and second devices. It is recommended to delete the exchange completion data sent.

  For example, if the exchange completion data deletion means receives a notification that the desired data has not been normally received from any one of the devices as a predetermined condition, the exchange registered by the first and second devices It is good to delete completion data.

  According to a fifth aspect of the present invention, there is provided a program for causing a computer device to exchange desired data and data owned by itself with another computer device that possesses desired data. A step of causing the computer apparatus to create first exchange completion data which is data necessary for reproducing the owned data, and the created first exchange completion data to the exchange completion data management apparatus that manages the exchange completion data. On the other hand, when the step of registering with the computer device and the communication with the other computer device are completed, the second exchange completion data, which is data necessary for reproducing the data acquired from the other computer device, is exchange completed. And causing the computer device to acquire from the data management device.

  A sixth aspect of the present invention is a program for causing a computer device to exchange desired data and data owned by itself with another computer device that owns desired data. A step of causing the computer apparatus to request the exchange completion data management apparatus that manages the exchange completion data to create the first exchange completion data that is data necessary for reproducing the owned data, and another computer apparatus When the communication with the computer is completed, the second exchange completion data, which is data necessary for reproducing the data obtained from another computer apparatus, is acquired from the exchange completion data management apparatus by the computer apparatus.

  According to a seventh aspect of the present invention, there is provided a computer device used in a system for exchanging data between computer devices connected via a communication medium, between the first computer device and the second computer device. Only when the exchange completion data management means for managing exchange completion data necessary for reproducing the exchanged data and the first and second computer apparatuses can successfully receive the desired data, the first The exchange completion data necessary for reproducing the data acquired by the second computer apparatus is transmitted to the first computer apparatus, and the exchange completion data necessary for reproducing the data acquired by the second computer apparatus is transmitted to the second computer apparatus. It is a program for functioning as exchange completion data transmission means to be transmitted to a computer device.

  According to the present invention, data exchanged between devices is not uploaded to a server (exchange completion data management device) that acts as an intermediary, and is the minimum data necessary for completion of data exchange (exchange completion data). Will be uploaded to the exchange completion data management device, which is the server. Therefore, the problem that the communication cost and the burden on the mediation server increase in proportion to the amount of data exchanged between devices is reduced. In addition, according to the present invention, only when two devices that have exchanged data normally receive the desired data, both devices can acquire the exchange completion data. When the communication is abnormally terminated, such as when the other party cannot receive the desired data normally, the device on the communication disconnecting side cannot obtain the exchange completion data. Accordingly, since both devices cannot reproduce desired data, a fair data exchange system is constructed.

  Furthermore, the role of the server serving as an intermediary is further reduced by causing the device to create the exchange completion data. In addition, since the device converts the data it owns into data that cannot be played back normally unless the exchange completion data is used and sends it to the counterpart device, the counterpart device does not acquire the exchange completion data. Data cannot be reproduced normally.

  On the other hand, since the server creates the exchange completion data, it is not necessary to provide means for creating the exchange completion data on the device side, so the burden on the device can be reduced.

  For example, the device encrypts the data, sends it to the other device, and reproduces the received data using the decryption key as the encryption exchange completion data, thereby diverting general encryption / decryption software. By doing so, the system of the present invention can be easily constructed.

  In addition, since the exchange completion data management device determines whether or not the exchanged device was able to receive data normally based on the information indicating the communication result sent from the device, the exchange of data is normally normal. Can be recognized.

  Further, when each device cannot receive the desired data to the end, it makes a retransmission request to the counterpart device, so that it is possible to receive the desired data to the end.

  Further, it is possible to create exchange completion data based on the exchange history with the device that has exchanged data so far, and to simplify the restoration process in the counterpart device. Therefore, it is possible to quickly exchange with a reliable partner, and an easy-to-use system is provided. Furthermore, since conversion of data to be transmitted can be simplified based on an exchange history with a device that has exchanged data so far, data exchange with a reliable partner can be performed more quickly.

  Further, if the predetermined condition is satisfied, the exchange completion data is deleted from the network, so that illegal use can be prevented by leaving the exchange completion data for a long time.

  By distributing the program of the present invention to each computer device, an easy-to-use device-to-device data exchange system is constructed, and content distribution is promoted.

(First embodiment)
FIG. 1 is a block diagram showing the overall configuration of an inter-device data exchange system Sa with a mediation server in the first embodiment of the present invention. In FIG. 1, the inter-device data exchange system Sa with an intermediary server includes a plurality of devices 11, an exchange completion data management device 21, a public data management device 31, and a transmission path 41. In FIG. 1, it is assumed that the device 11a and the device 11b exchange data. Hereinafter, when the device to be replaced is not particularly limited, it is referred to as the device 11, and when the device to be replaced is limited and described, the device 11a and the device 11b are used. In addition, the number of the apparatus 11, the exchange completion data management apparatus 21, the public data management apparatus 31, and the transmission line 41 is not limited to the number shown in FIG.

  The device 11 is a computer device having a communication function, such as a personal computer, a mobile communication terminal, and a mobile phone, and is owned by an exchange. The device 11 owns data in a storage device such as a hard disk or a memory. The device 11 registers and publishes a list of exchangeable data among the data owned by the device itself in the public data management device 31. A user who operates the device 11 refers to a list of public data registered in the public data management device 31 and recognizes another device 11 that holds desired data. When the user desires data exchange with another device 11, the device 11 communicates with the other device 11 to exchange data owned by the own device with data owned by the other device. At the time of data exchange, the device 11 converts the data owned by the device 11 into data that cannot be reproduced only by possessing the data by a predetermined conversion method, and transmits the data to another device 11. When the device 11 exchanges data with another device 11, after the data exchange is completed, the device 11 creates data necessary for normal reproduction of the data (hereinafter referred to as exchange completion data), and exchange completion data management Send to device 21 for management. When the data exchange with the exchange partner device 11 is normally completed, the device 11 receives the exchange completion data created by the exchange partner device 11 sent from the exchange completion data management device 21 and uses it. The data obtained by the exchange is played back.

  Here, the exchange completion data will be described. The exchange completion data is data necessary for normal reproduction of data from other devices 11 acquired by data exchange. Typical exchange completion data is a decryption key. When using the decryption key as exchange completion data, the device 11 encrypts and transmits the data owned by the device 11 using an encryption algorithm as the predetermined conversion method when exchanging data with the other device 11. After the data exchange ends normally, the device 11 receives the decryption key created by the exchange partner device 11 sent from the exchange completion data management device 21 and decrypts the data using the decryption key. Thereby, the acquired data can be reproduced normally. Hereinafter, the predetermined conversion method is referred to as a data conversion method.

  The exchange completion data includes, in addition, data for the climax part of the movie, data for the chorus part of music, data obtained by thinning out the original data randomly or regularly. As described above, when a part of the original data is used as the exchange completion data, when the device 11 reproduces the exchanged data, the device 11 adds the obtained exchange completion data and the exchanged data to obtain data that can be normally reproduced. Will get. The predetermined conversion method in a case where a part of the original data is used as the exchange completion data as the exchange data is a method of extracting a part of the original data.

  The exchange completion data management device 21 is a computer device such as a server and is owned by an exchange broker. The exchange completion data management device 21 manages exchange completion data created by each device 11. When the exchange completion data management apparatus 21 receives notification from the two devices 11 that exchanged data that the data exchange has been completed normally, the exchange completion data management device 21 transmits the managed exchange completion data to both devices 11.

  The public data management device 31 is a computer device such as a server and is owned by a public data manager. The public data management device 31 manages a list of data registered that the user of the device 11 can exchange as a public data list.

  The transmission path 41 is typically a high-speed communication network using an optical fiber such as FTTH, but is not limited to this, and is not limited to ADSL, the Internet, satellite broadcasting, a wireless communication network, a private LAN, and a wireless network. Any communication medium capable of transmitting and receiving electronic data such as a LAN may be used.

  FIG. 2 is a block diagram showing a functional configuration inside the device 11. In FIG. 2, the device 11 includes a data conversion unit 111, a message processing unit 112, a storage device control unit 113, a data storage device 114, a user input / output unit 115, and a data transmission / reception unit 116.

  The data conversion unit 111 converts the data passed from the message processing unit 112 according to a specified request using a predetermined data conversion method. The data conversion unit 111 may be realized by hardware such as a dedicated LSI, or may be realized by a program executed by a general-purpose CPU.

  The message processing unit 112 communicates with the data conversion unit 111, the storage device control unit 113, the user input / output unit 115, and the data transmission / reception unit 116, and processes a message given from each of them. The message processing unit 112 may be realized by hardware such as a dedicated LSI or may be realized by a program executed by a general-purpose CPU.

  The storage device control unit 113 performs data input / output processing with respect to the data storage device 114. The storage device control unit 113 may be realized by hardware including a dedicated LSI or the like, or may be realized by a device driver of the data storage device 114 that executes a general-purpose CPU.

  The data storage device 114 is a storage device such as a hard disk or a memory for recording various data. The data storage device 114 stores data that can be disclosed. The public data ID is associated with the public data corresponding to the data ID of the data. Furthermore, information for explaining the actual content of the data (hereinafter referred to as content information) is associated with the public data ID.

  FIG. 3 is a diagram illustrating an example of a data structure of data in which a data ID and a public data ID are associated with each other. In FIG. 3, for example, in a column D401, a data ID “DATA_ID-1111” and a public data ID “PUBLIC_DATA_ID-1111” are associated with each other. In the field D402, the data ID “DATA_ID-2222” and the public data ID “PUBLIC_DATA_ID-2222” are recorded in association with each other.

  FIG. 4 is a diagram illustrating an example of a data structure of data corresponding to the data ID of FIG. In FIG. 4, for example, a column D501 is a data ID, and a column D502 is a data entity corresponding to the data ID of the column D501. The data entity is digital data such as a movie or music. As described above, the data entity corresponding to the data ID is stored in the data storage device 114.

  FIG. 5 is a diagram showing a data structure of public content information corresponding to the public data ID of FIG. A column D601 is a disclosure data ID, and a column D602 is disclosure content information corresponding to the disclosure data ID in the column D601. The public content information includes, for example, a content name and information (remaining number of reproductions, expiration date) indicating how much rights remain for the content. Note that FIG. 5 shows an example in which “content name: blue town”, “remaining playback count: 7 times”, and “expiration date: March 31, 2003” as public content information.

  The device 11 uploads to the public data management device 31 a list in which the public data ID and the public content information are associated with each other. The list is managed by the public data management device 31 as a public data list.

  The user input / output unit 115 is an input device such as a keyboard, a mouse, or a button switch for accepting data input from a user who operates the device 11, and a display device such as a cathode ray tube or a liquid crystal screen for displaying data contents on the screen. An audio output device such as a speaker for outputting the contents of data as audio. The user input / output unit 115 performs data input processing and data output processing.

  The data transmission / reception unit 116 is a communication device such as a line termination device for transmitting / receiving data to / from another device 11, the exchange completion data management device 21, and the public data management device 31 via the transmission path 41.

  FIG. 6 is a block diagram illustrating a detailed functional configuration inside the data conversion unit 111. In FIG. 6, the data conversion unit 111 includes a pre-conversion data conversion processing unit 1111, an exchange completion data creation unit 1112, a post-conversion data conversion processing unit 1113, and a request determination unit 1114.

  The pre-conversion data conversion processing unit 1111 converts data owned by the device 11 based on a predetermined data conversion method. Hereinafter, the data before conversion is referred to as data before conversion. The converted data is called converted data. The pre-conversion data conversion processing unit 1111 sends the exchange completion data sent from the exchange completion data creation unit 1112 and the created post-conversion data to the message processing unit 112.

  For example, when an encryption method is used as the predetermined data conversion method, the pre-conversion data is data before encryption, and the post-conversion data is data after encryption. When a conversion method for extracting a climax part of a movie is used as a predetermined data conversion method, the converted data is data from which the climax part has been extracted. The same applies to the conversion method for extracting the rust portion. In addition, when the content provider designates the climax part and the rust part in advance, the pre-conversion data conversion processing unit 1111 can recognize the part. When the data thinning method is used as the predetermined data conversion method, the pre-conversion data conversion processing unit 1111 extracts the thinned portion specified from the pre-conversion data and creates post-conversion data.

  The exchange completion data creation unit 1112 creates conversion processing data necessary for converting the pre-conversion data into post-conversion data and exchange completion data necessary for returning the post-conversion data to the pre-conversion data. The data is sent to the data conversion processing unit 1111. When the data conversion processing unit 1111 uses an encryption method as the data conversion method, the exchange processing data is an encryption key for encrypting the data. The exchange completion data is decryption key data for decrypting the encrypted data.

  In addition, when a method of extracting a part of data is used as a data conversion method, the exchange processing data is extracted part designation data that designates a part to be extracted. Further, the exchange completion data is the extracted data. When a method of extracting a part of data is used as the data conversion method, the relationship of the processing flow between the exchange completion data creation unit 1112 and the pre-conversion data conversion processing unit 1111 is the processing shown in FIG. It will be mixed with the flow of. In the following description, for simplicity, an encryption method is used as a data conversion method unless otherwise specified. However, even when other data conversion methods are used, there is no essential difference in that the post-conversion data can be normally reproduced for the first time by creating the exchange completion data and using the exchange completion data. Changes are easy to implement.

  The post-conversion data conversion processing unit 1113 converts post-conversion data obtained from the other device 11 into pre-conversion data using the exchange completion data obtained from the exchange completion data management device 21, and sends it to the message processing unit 112. Specifically, when the exchange completion data is a decryption key, the post-conversion data conversion processing unit 1113 decrypts the encrypted post-conversion data using the exchange completion data to obtain pre-conversion data.

  The request determination unit 1114 determines the content of the request passed from the message processing unit 112 and executes predetermined processing. When the received request is a request for converting the pre-conversion data into the post-conversion data, the request determination unit 1114 sends the pre-conversion data received together with the request to the exchange completion data creation unit 1112. When the received request is a request for converting the converted data into the pre-conversion data, the request determination unit 1114 sends the converted data and the exchange completion data received together with the request to the converted data conversion processing unit 1113. send.

  FIG. 7 is a block diagram showing an internal functional configuration of the exchange completion data management device 21. 7, the exchange completion data management device 21 includes an exchange completion data transmission determination unit 211, a message processing unit 212, a storage device control unit 213, a data storage device 214, and a data transmission / reception unit 215.

  The exchange completion data transmission determination unit 211 creates a determination table in which the device ID and the exchange completion data transmitted from the device 11 are associated with each other, and whether or not the device 11 has notified that the data exchange has been normally completed. Is registered in the determination table, and it is determined whether or not the exchange completion data is transmitted to the device 11 based on the registered contents. Specifically, the exchange completion data transmission determination unit 211 receives the exchange completion data only when the notification that the data exchange has been completed normally is received from both of the two devices 11a and 11b that are exchanging data. Is transmitted to the two devices 11a and 11b. The exchange completion data transmission determination unit 211 may be realized by hardware such as a dedicated LSI or may be realized by a program executed by a general-purpose CPU.

  The message processing unit 212 communicates with the exchange completion data transmission determination unit 211, the storage device control unit 213, and the data transmission / reception unit 215 to process a message given from each. The message processing unit 212 may be realized by hardware such as a dedicated LSI or may be realized by a program executed by a general-purpose CPU.

  The storage device control unit 213 performs data input / output processing for the data storage device 214. The storage device control unit 213 may be realized by hardware including a dedicated LSI or the like, or may be realized by a device driver of the data storage device 214 that executes a general-purpose CPU.

  The data storage device 214 is a storage device such as a hard disk or a memory for recording various data. The data storage device 214 stores exchange completion data sent from the device 11 together with a determination table used for determining whether or not the exchange completion data is transmitted. The determination table corresponds to the ID of the device 11 that has transmitted the exchange completion data (hereinafter referred to as the device ID) and the device ID that are associated with the ID of the exchange completion data (hereinafter referred to as the exchange completion data ID). And a completion notification flag indicating whether or not the data exchange has been normally completed from the device 11 to be completed.

  FIG. 8 is a diagram illustrating an example of the data structure of the determination table. In FIG. 8, for example, in the determination table D901 whose determination table ID is “JUDGE_TABLE_ID-1111”, the device ID “CLIENT_ID-1111”, the exchange completion data ID “END_DATA_ID-1111”, and the completion notification flag “OFF” are displayed in the column D902. In the column D903, the device ID “CLIENT_ID-2222”, the replacement completion data ID “END_DATA_ID-2222”, and the completion notification flag “OFF” are recorded in association with each other. Here, in the completion notification flag, if there is a notification from the partner device that the data to be exchanged has been successfully received, “ON” is set, and something is wrong during the data exchange. Is generated, and “OFF” is set when there is a notification that the exchange target data could not be received. As described above, the determination table is used to manage the exchange completion data so that the transmission source device that has transmitted the exchange completion data can be identified.

  FIG. 9 is a diagram illustrating an example of the data structure of exchange completion data corresponding to the exchange completion data ID of FIG. In FIG. 9, a column D1001 shows the exchange completion data ID, and a column D1002 shows the substance of the exchange completion data corresponding to the exchange completion data ID of D1001. Here, the substance of the exchange completion data is the contents of the exchange completion data sent from the device 11. As described above, the data storage device 214 stores the exchange completion data together with the determination table.

  The data transmission / reception unit 215 is a communication device for transmitting / receiving data to / from the device 11 and the public data management device 31 via the transmission path 41.

  FIG. 10 is a block diagram illustrating a detailed functional configuration inside the exchange completion data transmission determination unit 211. In FIG. 10, the exchange completion data transmission determination unit 211 includes a determination table reference unit 2111, a determination table creation unit 2112, and a request determination unit 2113.

  The request determination unit 2113 determines the content of the request passed from the message processing unit 212 and executes predetermined processing. If the passed request is a request for requesting registration of replacement completion data, the request determination unit 2113 sends the replacement destination and source device IDs and the replacement completion data IDs from both to the determination table creation unit 2112. Pass and request creation of decision table. In the case where the passed request is a request for transmission completion data exchange based on the data exchange completion notification notified from the device 11, the request determination unit 2113 receives the device ID of the device 11 that made the completion notification. Then, the determination table ID corresponding to the device ID and the completion notification information included in the completion notification are passed to the determination table reference unit 2111 to request transmission determination of exchange completion data.

  The determination table creation unit 2112 creates a determination table based on the data notified from the request determination unit 2113, stores the determination table in the data storage device 214, and sends the ID of the determination table to the message processing unit 212. Note that a path for the determination table creation unit 2112 to store the determination table in the data storage device 214 is not shown.

  Based on the data notified from the request determination unit 2113, the determination table reference unit 2111 refers to the determination table stored in the data storage device 214 and determines whether or not to send the exchange completion data. Specifically, when both of the completion notification flags in the determination table are “OK”, that is, when the notification that the data exchange is normally completed is received from the two devices 11 that exchanged data. Only the determination table reference unit 2111 determines that the exchange completion data may be transmitted. When it is determined that transmission is possible, the determination table reference unit 2111 sends the device ID of the transmission destination device 11 and the exchange completion data ID to the message processing unit 212.

  FIG. 11 is a block diagram showing an internal functional configuration of the public data management device 31. In FIG. 11, the public data management device 31 includes a message processing unit 311, a storage device control unit 312, a data storage device 313, and a data transmission / reception unit 314.

  The message processing unit 311 communicates with the storage device control unit 312 and the data transmission / reception unit 314 to process messages given from the respective units. The message processing unit 311 may be realized by hardware including a dedicated LSI or the like, or may be realized by a program executed by a general-purpose CPU.

  The storage device control unit 312 performs data input / output processing on the data storage device 313. The storage device control unit 312 may be realized by hardware including a dedicated LSI or the like, or may be realized by a device driver of the data storage device 313 that executes a general-purpose CPU.

  The data transmission / reception unit 314 is a communication device for transmitting / receiving data to / from the device 11 and the exchange completion data management device 21 via the transmission path 41.

  The data storage device 313 is a storage device such as a hard disk or a memory for recording various data. The data storage device 313 stores a public data list. The public data list includes a public data ID and a device ID (hereinafter referred to as a registered device ID) of the device 11 that has registered the data. Content information is associated with the public data ID.

  FIG. 12 is a diagram illustrating an example of the data structure of the public list data. In FIG. 12, for example, a registered device ID “CLIENT_ID-1111” and a public data ID “PUBLIC_DATA_ID-1111” are associated and recorded in a column D1201, and a registered device ID “CLIENT_ID-2222” is disclosed in a column D1202. The data ID “PUBLIC_DATA_ID-2222” is recorded in association with each other.

  FIG. 13 is a diagram illustrating an example of a data structure of content information corresponding to the public data ID of FIG. In FIG. 13, a column D1301 shows the data ID for disclosure. A column D1302 indicates content information corresponding to the public data ID in the column D1301. In FIG. 13, “content name: blue city”, “remaining playback count: 7 times”, and “expiration date: March 31, 2003” are registered as content information.

  The flow of processing in the inter-device data exchange system Sa configured as described above will be described below. Processing in this system can be classified into three scenes. The first scene is a scene in which public data owned by the device 11 is registered in the public data management device 31. The second scene is a scene in which the device 11a acquires the device ID corresponding to the public data ID designated by the user from the public data management device 31. The third scene is a scene in which the device 11a exchanges data with the device 11b and the exchange completion data management device 21. Hereinafter, operations of the device 11, the exchange completion data management device 21, and the public data management device 31 in each scene will be described.

(Sequence in the registration of public data)
First, the operations of the device 11 and the public data management device 31 in a scene where the public data owned by the device 11 is registered in the public data management device 31 will be described with reference to FIGS. 14 and 15.

  FIG. 14 is a sequence diagram illustrating operations of the device 11 and the public data management device 31 when registering content information related to public data owned by the device 11 in the public data management device 31. In FIG. 14, the timing at which each step is performed is surrounded by a square white frame so that the subject of the operation in the device 11 and the data and messages exchanged from the functional block to the functional block are clear. Etc. are described on the arrows connecting the functional blocks. The functional block realized by software is realized by a function programmed so as to follow the flow shown in the sequence diagram. A functional block realized in hardware can be realized if it is designed to operate in accordance with the flow shown in the sequence diagram. The same applies to the sequence diagrams of FIG. 14 and subsequent figures.

  First, in response to a user input operation, the user input / output unit 115 of the device 11 acquires a data ID of data that the user desires to register, notifies the message processing unit 112 of the data ID, and releases the data for publication. Registration is requested (step S1401).

  Next, in response to the public data registration request, the message processing unit 112 acquires the data ID included in the request, notifies the storage device control unit 113 of the data ID, and transmits the public data to the data storage device. Request to obtain from 114 (step S1402).

  Next, in response to the public data acquisition request, the storage device control unit 113 acquires the data ID included in the request, and stores the public data ID corresponding to the data ID and the content information of the public data. Obtained from the storage device 114, and sends the obtained public data ID and content information to the message processing unit 112 (step S1403).

  Next, when the message processing unit 112 receives the disclosure data ID and the content information, the message processing unit 112 creates a disclosure data registration message including the disclosure data ID, the content information, and the device ID of the own device, It transmits to the transmission / reception part 116 (step S1404). Upon receiving the public data registration message, the data transmission / reception unit 116 transmits the message to the public data management device 31 (step S1405).

  When the public data management device 31 receives the public data registration message from the device 11, the public data management device 31 creates a public data list based on the public data ID and the device ID included in the message, and the corresponding content information And an ACK message indicating the result of the registration process of registration data is transmitted to the device 11 (step S1406).

  When receiving the ACK message from the public data management device 31, the data transmission / reception unit 116 transmits the message to the message processing unit 112 (step S1407).

  When the message processing unit 112 receives the ACK message, the message processing unit 112 transmits information on the registration result included in the message to the user input / output unit 115 (step S1408). In response to this, the user input / output unit 115 notifies the user of registration result information by screen display or the like (step S1409).

  FIG. 15 is a sequence diagram illustrating operations of the public data management device 31 and the device 11 when the public data management device 31 receives a public data registration message. In FIG. 15, the same operations as those shown in FIG. 14 are denoted by the same step numbers and the description thereof is omitted. The sequence diagram shown in FIG. 15 is a diagram showing in detail the operation of the public data management apparatus 31 in step S1406 of FIG.

  First, the data transmission / reception unit 314 of the public data management device 31 receives a public data registration message from the device 11, and transmits the message to the message processing unit 311 (step S1501).

  Next, when the message processing unit 311 receives the disclosure data registration message, the message processing unit 311 extracts the disclosure data ID, the content information, and the device ID in the message, and sends a disclosure data registration request including them to the storage device control unit. It transmits to 312 (step S1502).

  Upon receipt of the public data registration request, the storage device control unit 312 associates the public data ID in the request with the content information, and creates a public data list by associating the public data ID with the device ID. The data is stored in the data storage device 313 and the registration result is transmitted to the message processing unit 311 (step S1503).

  When receiving the registration result, the message processing unit 311 transmits an ACK message including information on the registration result to the data transmission / reception unit 314 (step S1504). When receiving the ACK message, the data transmission / reception unit 314 transmits the message to the device 11 (step S1505).

(Sequence in the scene of acquiring the device ID)
Next, with reference to FIGS. 16 and 17, the operation of the device 11 a and the public data management device 31 in a scene where the device 11 acquires the device ID corresponding to the public data ID specified by the user from the public data management device 31. Will be described.

  FIG. 16 is a sequence diagram illustrating the operation of the device 11a when acquiring the device ID. First, the user input / output unit 115 of the device 11a acquires a public data ID of data that the user desires to exchange, and transmits a registration device ID acquisition request including the public data ID to the message processing unit 112. (Step S1601). Here, it is assumed that the public data ID can be obtained from a public data list or the like published by the public data management device 31. Here, it is assumed that the device 11a acquires the public data ID registered by the device 11b.

  Next, when the message processing unit 112 receives the registration device ID acquisition request, the message processing unit 112 acquires the public data ID in the request, creates a registered device ID acquisition message including the data ID, and transmits it to the data transmission / reception unit 116. (Step S1602).

  Upon receiving the registered device ID acquisition message, the data transmitting / receiving unit 116 transmits the message to the public data management device 31 (step S1603).

  When receiving the registered device ID acquisition message from the device 11a, the public data management device 31 acquires the registered device ID corresponding to the public data ID in the message (here, the device ID of the device 11b is acquired), and An ACK message including the registered device ID is transmitted to the device 11a (step S1604).

  When receiving the ACK message from the public data management device 31, the data transmission / reception unit 116 transmits the message to the message processing unit 112 (step S1605). When receiving the ACK message, the message processing unit 112 extracts the registered device ID in the message and transmits the registered device ID to the user input / output unit 115 (step S1606). The user input / output unit 115 uses the transmitted registered device ID to specify a communication partner device when performing data exchange.

  FIG. 17 is a sequence diagram showing operations of the public data management device 31 and the device 11a when the public data management device 31 receives a registered device ID acquisition message. 17, the same operations as those shown in FIG. 16 are denoted by the same step numbers and the description thereof is omitted. Note that the sequence diagram shown in FIG. 17 is a diagram showing in detail the operation of the public data management apparatus 31 in step S1604 of FIG.

  First, the data transmission / reception unit 314 of the public data management device 31 receives the registered device ID acquisition message from the device 11a and transmits the message to the message processing unit 311 (step S1701).

  When the message processing unit 311 receives the registered device ID acquisition message, the message processing unit 311 extracts the public data ID in the message, and transmits a registered device ID acquisition request including the ID to the storage device control unit 312 (step S1702).

  When receiving the registered device ID acquisition request, the storage device control unit 312 acquires the registered device ID corresponding to the public data ID in the request from the data storage device 313 and transmits the registered device ID to the message processing unit 311. (Step S1703).

  When the message processing unit 311 receives the registered device ID, the message processing unit 311 creates an ACK message including the registered device ID and transmits the ACK message to the data transmission / reception unit 314 (step S1704).

  When receiving the ACK message, the data transmission / reception unit 314 transmits the message to the device 11a (step S1705).

(Sequence in data exchange scene)
Next, a sequence for exchanging data between the two devices 11a and 11b with the exchange completion data management device 21 will be described with reference to FIGS.

  FIG. 18 is a sequence diagram showing the operations of the device 11a and the device 11b until the device 11a makes a data exchange offer to the device 11b and receives a response. First, the user input / output unit 115 of the device 11a has a public data ID of data that the user wants to exchange, and a device ID that owns the data (the device of the device that has registered the public data ID in the public data management device 31). ID) and a data exchange request including the two IDs is transmitted to the message processing unit 112 (step S1801). The acquisition processing of the public data ID and the device ID has been described with reference to FIGS.

  When the message processing unit 112 receives the data exchange request, the message processing unit 112 stores all the public data IDs registered in the public data management device 31 by the device 11a and all the content information corresponding to the public data IDs. A public data acquisition request for acquisition from the storage device 114 is transmitted to the storage device control unit 113 (step S1802).

  Next, when receiving the disclosure data acquisition request, the storage device control unit 113 receives from the data storage device 114 content information corresponding to all the disclosure data IDs registered in the disclosure data management device 31 by the device 11a. It is acquired and transmitted to the message processing unit 112 (step S1803).

  Next, the message processing unit 112 receives the public data ID and content information sent thereto, and sends a data exchange message including the device ID and the public data ID acquired in step S1801 to the data transmission / reception unit 116. (Step S1804).

  In response to this, the data transmitting / receiving unit 116 transmits the received data exchange message to the device 11b (step S1805).

  Upon receiving the data exchange message from the device 11a, the device 11b selects a public data ID that the user desires to exchange from within the message according to the operation shown in FIG. 23 described later, and includes the selected public data ID. An ACK message is transmitted to the device 11a (step S1806). However, when there is no data that the user desires to exchange, the device 11b transmits an ACK message including information indicating that.

  When receiving the ACK message from the device 11b, the data transmitting / receiving unit 116 transmits the message to the message processing unit 112 (step S1807).

  FIG. 19 shows the device from when the device 11a receives an ACK message received from the device 11b including a public data ID that is desired to be exchanged to the exchange completion data management device 21 for an intermediary process and to receive a response. It is a sequence diagram which shows operation | movement of 11a and the exchange completion data management apparatus 21. FIG. In FIG. 19, operations similar to those shown in FIG. 18 are denoted by the same step numbers and description thereof is omitted.

  The message processing unit 112 receives the ACK message and determines whether or not the exchange data ID is included in the ACK message. If included, the message processing unit 112 transmits an exchange target data acquisition request including the exchange data ID to the storage device control unit 113 (step S1808). On the other hand, if not included, the message processing unit 112 transmits information indicating that to the user input / output unit 115. In response, the user input / output unit 115 notifies the user that the data exchange is rejected to the device 11b.

  Next, when the storage device control unit 113 receives the exchange target data acquisition request, the storage device control unit 113 refers to the data storage device 114 to acquire the data ID corresponding to the replacement data ID in the request, and corresponds to the data ID. Data is acquired, and the acquired data (hereinafter referred to as exchange target data) is transmitted to the message processing unit 112 (step S1809).

  When the message processing unit 112 receives the exchange target data, the message processing unit 112 transmits the exchange target data to the data conversion unit 111 and gives a request for conversion into converted data (hereinafter referred to as a data conversion request) (step S1810). .

  When receiving the data conversion request, the data conversion unit 111 converts the pre-conversion data in the request, creates post-conversion data and exchange completion data, and sends the post-conversion data and exchange completion data to the message processing unit 112. Transmit (step S1811).

  Next, when receiving the converted data and the exchange completion data, the message processing unit 112 creates an exchange completion data registration message including the exchange completion data and the device ID, and transmits the message to the data transmission / reception unit 116 (step S1812). ).

  When receiving the exchange completion data registration message, the data transmitter / receiver 116 transmits the message to the exchange completion data management device 21 (step S1813).

  Although not described here, the device 11b also performs the same processing as the device 11a and transmits the exchange completion data to the exchange completion data management device 21.

  When the exchange completion data management device 21 receives the exchange completion data registration message from the devices 11a and 11b, the exchange completion data management device 21 creates a determination table according to the operation shown in FIG. 24 described later, and exchange completion data included in the received message. Is stored, the ACK message including the determination table ID is transmitted to the device 11a and the device 11b (step S1814).

  Next, when receiving the ACK message from the exchange completion data management device 21, the data transmission / reception unit 116 of the device 11a transmits the message to the message processing unit 112 (step S1815).

  FIG. 20 is a sequence diagram showing operations of the device 11a and the device 11b after the device 11a receives an ACK message from the exchange completion data management device 21 until data exchange with the device 11b is started. In FIG. 20, the same operations as those shown in FIG. 19 are denoted by the same step numbers and the description thereof is omitted.

  First, when the message processing unit 112 of the device 11a receives an ACK message, the message processing unit 112 transmits an exchange start message to the data transmission / reception unit 116 (step S1816).

  Next, when receiving the exchange start message, the data transmitting / receiving unit 116 transmits the message to the device 11b (step S1817).

  Upon receipt of the exchange start message from the device 11a, the device 11b creates an ACK message and transmits the message to the device 11a according to the operation shown in FIG. 25 (step S1818).

  When receiving the ACK message from the device 11b, the data transmitting / receiving unit 116 of the device 11a transmits the message to the message processing unit 112 (step S1819).

  Thereafter, data exchange is started between the device 11a and the device 11b (step S1820). As a communication method at the time of data exchange, a known technique such as packet communication is used.

  FIG. 21 is a sequence diagram showing operations of the device 11a and the exchange completion data management device 21 from when the device 11a finishes communication with the device 11b until it receives an ACK message from the exchange completion data management device 21. In FIG. 21, the same operations as those shown in FIG. 20 are denoted by the same step numbers and the description thereof is omitted.

  First, when the communication with the device 11b is completed, the message processing unit 112 determines whether or not the target exchange target data has been successfully acquired from the device 11b (step S1821a). The determination as to whether or not the data has been acquired normally is made when the devices 11a and 11b exchange the sizes of the data scheduled to be transmitted in advance and the data size of the received data is smaller than the planned data size. This can be realized by determining that the exchange target data could not be received normally.

  If the message is successfully acquired, the message processing unit 112 creates an exchange completion notification message including information indicating exchange completion (hereinafter referred to as “OK information”) and a determination table ID (step S1821b). On the other hand, if not successfully acquired, the message processing unit 112 creates an exchange completion notification message including information indicating an exchange failure (hereinafter referred to as NG information) and a determination table ID (step S1821c). Next, the message processing unit 112 transmits the created exchange completion notification message to the data transmission / reception unit 116 (step S1821d).

  When receiving the exchange completion notification message, the data transmission / reception unit 116 transmits the message to the exchange completion data management device 21 (step S1822). Although not described here, the device 11b also performs the same processing as the device 11a, and transmits an exchange completion notification message to the exchange completion data management device 21.

  When the exchange completion data management device 21 receives the exchange completion notification message from the device 11a and the device 11b, the exchange required by the device 11a and the device 11b is performed based on the determination table according to the operation shown in FIG. It is determined whether or not the completion data is transmitted to the device 11a and the device 11b. When it is determined that the exchange completion data is to be transmitted, the exchange completion data management device 21 transmits an ACK message including the exchange completion data to the devices 11a and 11b. On the other hand, when it is determined that the exchange completion data is not transmitted, the exchange completion data management device 21 transmits an ACK message not including the exchange completion data to the devices 11a and 11b (step S1823). Details of the determination as to whether or not to transmit the exchange completion data will be described later with reference to FIG.

  The data transmission / reception unit 116 transmits an ACK message from the exchange completion data management device 21 to the message processing unit 112 (step S1824a).

  FIG. 22 is a sequence diagram showing the operation of the device 11a after receiving the ACK message from the exchange completion data management device 21. In FIG. 22, the same operations as those shown in FIG. 21 are denoted by the same step numbers and the description thereof is omitted.

  First, the message processing unit 112 analyzes the ACK message from the exchange completion data management device 21 and determines whether or not exchange completion data is included (step S1825a). If not included, the message processing unit 112 transmits information indicating that to the user input / output unit 115. In response to this, the message processing unit 112 notifies the user that the exchange target data cannot be reproduced because the exchange completion data could not be acquired (step S1825b).

  On the other hand, if it is included, the message processing unit 112 extracts the exchange completion data, and transmits a data conversion request including the exchange completion data and the converted data acquired from the device 11b to the data conversion unit 111 (step). S1825c).

  When receiving the data conversion request, the data conversion unit 111 creates pre-conversion data based on the exchange completion data and the converted data in the request, and transmits the pre-conversion data to the message processing unit 112 (step S1826).

  Next, when acquiring the pre-conversion data, the message processing unit 112 transmits a data registration request including the pre-conversion data to the storage device control unit 113 (step S1827). When the storage device control unit 113 receives the data registration request, the storage device control unit 113 extracts data in the request, assigns a new data ID, registers the data ID in the data storage device 114, and sends information indicating the registration result to the message processing unit 112. Transmit (step S1828).

  Next, when receiving the information indicating the registration result, the message processing unit 112 transmits information indicating the completion of the exchange to the user input / output unit 115 (step S1829). Finally, the user input / output unit 115 notifies the user that the data exchange has been completed (step S1830).

  FIG. 23 is a sequence diagram showing the operation of the device 11b when the device 11b receives the data exchange message from the device 11a. In FIG. 23, the same operations as those shown in FIG. 18 are denoted by the same step numbers, and the description thereof is omitted. The operation shown in FIG. 23 shows the operation of the device 11b in step S1806 in FIG. 18 in detail.

  When receiving the data exchange message from the device 11a, the data transmission / reception unit 116 of the device 11b transmits the message to the message processing unit 112 (step S1901).

  Next, when receiving the data exchange message, the message processing unit 112 extracts all the public data IDs and all the corresponding content information in the message, and sends a data selection request including them to the user input / output unit 115. (Step S1902).

  When the user input / output unit 115 receives the data selection request, the user input / output unit 115 presents all the public data IDs in the request and all the corresponding content information to the user, and causes the user to select the data desired to be exchanged. In response to this, the user selects data desired to be exchanged from the presented public data. On the other hand, if there is no particular data desired to be exchanged, the user selects information indicating that. The user input / output unit 115 transmits the public data ID corresponding to the public data selected by the user to the message processing unit 112 (step S1903). If not selected, the user input / output unit 115 transmits information indicating that to the message processing unit 112 instead of the public data ID.

  When the message processing unit 112 receives the public data ID or the information indicating no selection, the message processing unit 112 transmits an ACK message including them to the data transmission / reception unit 116 (step S1904). When receiving the ACK message, the data transmitting / receiving unit 116 transmits the message to the device 11a (step S1905).

  FIG. 24 is a sequence diagram showing the operation of the exchange completion data management apparatus 21 when the exchange completion data management apparatus 21 receives an exchange completion data registration message from the devices 11a and 11b. In FIG. 24, the same operations as those shown in FIG. 19 are denoted by the same step numbers and description thereof is omitted. The operation shown in FIG. 24 shows in detail the operation of the exchange completion data management apparatus 21 in step S1814 of FIG.

  When receiving the exchange completion data registration message from the device 11a and the device 11b, the data transmission / reception unit 215 of the exchange completion data management device 21 transmits the message to the message processing unit 212 (step S2001).

  When the message processing unit 212 receives the exchange completion data registration message, the message processing unit 212 transmits a determination table creation request including the exchange completion data ID and the device ID in the message to the exchange completion data transmission determination unit 211 (step S2002).

  Upon receiving the determination table creation request, the exchange completion data transmission determination unit 211 creates a determination table by associating the device ID included in the request with the replacement completion data ID, and sends the determination table ID of the determination table as a message. The data is transmitted to the processing unit 212 (step S2003).

  When the message processing unit 212 receives the determination table ID, the message processing unit 212 extracts the exchange completion data and the exchange completion data ID in the exchange completion data registration message received from the device 11a and the device 11b, and exchange completion data including such information. A registration request is transmitted to the storage device control unit 213 (step S2004).

  Next, when the storage device control unit 213 receives the exchange completion data registration request, the storage device control unit 213 stores the exchange completion data and the exchange completion data ID in the request in association with each other in the data storage device 214, and displays information indicating the registration result as a message. The data is transmitted to the processing unit 212 (step S2005).

  When the message processing unit 212 receives the information indicating the registration result, the message processing unit 212 transmits an ACK message including the determination table ID to the data transmission / reception unit 215 (step S2006). When receiving the ACK message, the data transmission / reception unit 215 transmits the message to the device 11a and the device 11b (step S2007).

  FIG. 25 is a sequence diagram showing the operation of the device 11b when the device 11b receives the exchange start message from the device 11a. In FIG. 25, the same operations as those shown in FIG. 20 are denoted by the same step numbers and the description thereof is omitted. The operation shown in FIG. 25 shows the operation of the device 11b in step S1818 in FIG. 20 in detail.

  When receiving the exchange start message from the device 11a, the data transmitting / receiving unit 116 of the device 11b transmits the message to the message processing unit 112 (step S2101). When receiving the exchange start message, the message processing unit 112 confirms the exchange content and transmits an ACK message to the data transmission / reception unit 116 (step S2102). When receiving the ACK message, the data transmitter / receiver 116 transmits the message to the device 11a (step S2103).

  FIG. 26 is a sequence diagram showing the operation of the exchange completion data management device 21 when the exchange completion data management device 21 receives the exchange completion notification message from the devices 11a and 11b. In FIG. 26, the same operations as those shown in FIG. 21 are denoted by the same step numbers and the description thereof is omitted. The operation shown in FIG. 26 shows in detail the operation of the exchange completion data management apparatus 21 in step S1823 of FIG.

  When receiving the exchange completion notification message from the device 11a and the device 11b, the data transmission / reception unit 215 of the exchange completion data management device 21 transmits the message to the message processing unit 212 (step S2201).

  Upon receiving the exchange completion notification message from the device 11a and the device 11b, the message processing unit 212 receives the determination table ID and the exchange end information (OK information indicating the exchange completion or NG information indicating the exchange failure) in the messages. ) And the device ID are extracted, registered in the determination table, the determination table ID is designated, and whether or not the replacement completion data may be transmitted to the devices 11a and 11b is determined as the replacement completion data transmission determination unit 211. (Step S2202).

  When the exchange completion data transmission determination unit 211 receives the exchange completion data transmission determination request, the exchange completion data transmission determination unit 211 refers to the determination table corresponding to the determination table ID in the request and notifies the completion of both the device IDs of the device 11a and the device 11b. It is determined whether or not OK information is registered in the flag (step S2203a). When OK information is registered in both, the exchange completion data transmission determination unit 211 transmits the exchange completion data corresponding to the device ID of the device 11b to the device 11a, and the exchange completion data corresponding to the device ID of the device 11a. In order to transmit to the device 11b, the device ID and the corresponding exchange completion data ID are transmitted to the message processing unit 212 and requested (step S2203b). On the other hand, if NG information is registered in one of the determination tables, the exchange completion data transmission determination unit 211 transmits information indicating that the exchange completion data transmission is not possible to the message processing unit 212, and accordingly, the message The processing unit 212 transmits an ACK message indicating that the exchange completion data cannot be acquired to the devices 11a and 11b (steps 2203c and 2203d).

  When the message processing unit 212 receives the device ID and the exchange completion data ID, the message processing unit 212 transmits the exchange completion data ID to the storage device control unit 213 and controls the storage device to acquire the corresponding exchange completion data from the data storage device 214. A request is made to the unit 213 (hereinafter referred to as an exchange completion data acquisition request) (step S2204).

  When the storage device control unit 213 receives the exchange completion data acquisition request, the storage device control unit 213 acquires the exchange completion data corresponding to the exchange completion data ID in the request from the data storage device 214, and sends the acquired exchange completion data to the message processing unit 212. Transmit (step S2205).

  When the message processing unit 212 receives the exchange completion data, the message processing unit 212 transmits the exchange completion data corresponding to the device ID of the device 11b to the device 11a and the exchange completion data corresponding to the device ID of the device 11a to the device 11b. An ACK message including completion data is transmitted to the data transmitter / receiver 215 (step S2206). When receiving the ACK message, the data transmission / reception unit 215 transmits the message to the device 11a and the device 11b as specified by the transmission destination (step S2207).

  As described above, in the first embodiment, data itself exchanged between devices is not uploaded to the exchange completion data management device, and only the minimum data necessary for completion of data exchange (exchange completion data) is stored. The data is uploaded to the exchange completion data management device. Therefore, the problem that the communication cost and the burden on the mediation server increase in proportion to the amount of data exchanged between devices is reduced. In addition, only when the two devices that exchanged data successfully receive the desired data, both devices can obtain the exchange completion data, so the communication is cut off halfway, When communication ends abnormally, for example, when the other party cannot receive desired data normally, the device on the communication disconnecting side cannot acquire replacement completion data. Accordingly, since both devices cannot reproduce desired data, a fair data exchange system is constructed.

  Furthermore, the role of the exchange completion data management device is further reduced by causing the device to create exchange completion data. In addition, since the device converts the data it owns into data that cannot be played back normally unless the exchange completion data is used and sends it to the counterpart device, the counterpart device does not acquire the exchange completion data. Data cannot be reproduced normally.

  For example, the device encrypts the data, sends it to the other device, and reproduces the received data using the decryption key as the encryption exchange completion data, thereby diverting general encryption / decryption software. By doing so, the system of the present invention can be easily constructed.

  In addition, since the exchange completion data management device determines whether or not the exchanged device was able to receive data normally based on the information indicating the communication result sent from the device, the exchange of data is normally normal. Can be recognized.

  Also, by distributing the program of the present invention to each computer device, an easy-to-use device-to-device data exchange system is constructed, and content distribution is promoted.

  Note that the device 11, the exchange completion data management device 21, and the public data management device 31 shown in the first embodiment may be realized by a program for causing a general-purpose computer device to execute the above-described operation. Such a program is stored in a recording medium such as a hard disk, an optical disk, a CD-ROM, or a memory, and is executed by a CPU or the like.

  In the first embodiment, each device creates the exchange completion data and transmits it to the exchange completion data management device. However, the exchange completion data management device may create the exchange completion data. Hereinafter, a system in which the exchange completion data management apparatus creates exchange completion data will be described. For example, when a decryption key is used as exchange completion data, each device requests the exchange completion data management device to create a decryption key when it is desired to exchange data with other devices. In response to this, the exchange completion data management apparatus creates a decryption key and a corresponding encryption key. The exchange completion data management apparatus registers and manages the created decryption key in the determination table so that the requesting device that made the creation request can be identified. Then, the exchange completion data management device transmits the created encryption key to the requesting device. When the encryption key is sent, the device encrypts the data to be exchanged using the encryption key and creates converted data. The converted data can be decrypted by using the decryption key registered in the exchange completion data. The device transmits the encrypted converted data to the exchange partner device, and obtains desired data from the exchange partner device. Thereafter, in the same manner as in the above embodiment, the device acquires the decryption key from the exchange completion data management device, restores the converted data received from the exchange partner device, and reproduces it. In this way, when the exchange completion data management device creates the decryption key, the exchange completion data management device also creates an encryption key corresponding to the created decryption key at the same time, and sends it back to the device that requested the creation of the decryption key. It will be. It can be said that the encryption key is data (hereinafter referred to as conversion processing data) for converting the pre-conversion data so that the post-conversion data can be normally reproduced by using the decryption key. In this case as well, the exchange completion data may be other than the decryption key. Further, the conversion processing data may be other than the encryption key. Furthermore, the device in the system in which the management apparatus creates replacement completion data and the replacement completion data management apparatus are also realized by a program that causes a computer device to execute the above-described operation. In this way, since the exchange completion data management device creates the exchange completion data, it is not necessary to provide a means for creating the exchange completion data on the device side, so the burden on the device can be reduced. . This is effective when a device having a low processing capability is used.

  In the first embodiment, when the size of data scheduled to be transmitted is exchanged between devices in advance and the data size of the received data is smaller than the planned data size, the data to be exchanged normally Although the device determines that the data could not be received, the method for determining whether or not the exchange target data has been normally received is not limited to this. For example, each device obtains a hash value of the converted data and registers the hash value in the exchange completion data management device 21 together with the exchange completion data. Then, when the communication with the counterpart device is completed, each device obtains a hash value of the received data and transmits it to the exchange completion data management device 21. In response to this, the exchange completion data management device 21 compares the registered hash value with the received hash value, and if the hash values match, determines that the data exchange has been performed normally, If the hash values do not match, it is determined that data exchange has not been performed normally. By using the hash value in this way, part of the exchange target data is lost on the transmission path, so even if the exchange target data that could not be reproduced but could be reproduced is obtained normally. It is possible to determine that data exchange has been performed, which is useful. Naturally, the information is not limited to the above as long as the information indicating the communication result is sent from the device as information that allows the exchange completion data management unit to determine whether or not the data exchange has been normally performed.

  In the first embodiment, when the exchange target data cannot be normally received, the device transmits the NG information to the exchange completion data management device. However, the OK information is received from the two devices. If the exchange completion data management unit transmits the exchange completion data only in this case, the NG information need not be transmitted.

  Here, a procedure for deleting the exchange completion data stored in the exchange completion data management apparatus 21 will be described. FIG. 27 is a flowchart showing the operation of the exchange completion data management apparatus 21 until the exchange completion data is deleted. The operation shown in FIG. 27 is performed after the exchange completion data management apparatus 21 transmits an ACK message in FIG.

  First, the exchange completion data management device 21 refers to the determination table to determine whether or not the two devices 11a and 11b that have exchanged data have both sent OK information (step S2701). If both pieces of OK information have been sent, the exchange completion data management device 21 determines whether or not an ACK message indicating that the exchange completion data has been successfully acquired has been received from both devices 11a and 11b (step). S2702).

  If received, it indicates that the exchange completion data has been successfully acquired by both the devices 11a and 11b, so the exchange completion data management device 21 deletes the stored exchange completion data and the determination table corresponding thereto. (Step S2703), and the process ends. On the other hand, if it has not been received, since the exchange completion data has not normally reached the device due to a communication error or the like, the exchange completion data management device 21 has transmitted an ACK message indicating that the exchange completion data could not be obtained normally. The exchange completion data is retransmitted to the device (step S2704), and the process returns to step S2702.

  If neither OK information has been sent in step S2701, the exchange completion data management device 21 determines whether either one has sent NG information (step S2705). If either one has sent the NG information, the exchange completion data management device deletes the exchange completion data stored and the determination table corresponding thereto (step S2703), and ends the process.

  On the other hand, if either one has not sent NG information but there is no response from at least one, the exchange completion data management device 21 determines whether or not a predetermined time has elapsed (step S2706). If not, the exchange completion data management device 21 returns to the operation of step S2701. On the other hand, if it has elapsed, the exchange completion data management device 21 deletes the exchange completion data stored and the determination table corresponding to the exchange completion data (step S2703), and ends the process.

  As described above, if the predetermined condition is satisfied, the exchange completion data is deleted from the network. Therefore, it is possible to prevent unauthorized use due to the exchange completion data remaining for a long time.

(Second Embodiment)
In the second embodiment of the present invention, data to be exchanged can be received halfway from another device, but if the data cannot be received to the end, the device can acquire the remaining data that could not be received. The system will be described. Also in the second embodiment, since the configuration of the entire system is the same as that of the first embodiment, FIG. 1 is used.

  FIG. 28 is a sequence diagram illustrating operations of the device 11a and the device 11b when the device 11a requests the device 11b to retransmit the exchange target data. First, when communication with the device 11b is completed, the message processing unit 112 of the device 11a determines whether the size of the received data is smaller than the total size of the exchange target data sent from the device 11b in advance. (Step S2801).

  If it is smaller, the message processing unit 112 causes the data transmission / reception unit 116 to transmit a retransmission request including the size of the already received data to the device 11b (step S2802). In response to this, the message processing unit 112 of the device 11b recognizes the remaining data based on the received data size, causes the storage device control unit 113 to acquire the remaining data from the data storage device 114, and transmits and receives data. The unit 116 is caused to transmit the remaining data to the device 11a (step S2803). The device 11a receives the remaining data transmitted from the device 11b, combines it with the already received data, stores it, and returns to the operation of step S2801.

  On the other hand, if it is not small, that is, if the reception size and the total size are the same, the message processing unit 112 sends an exchange completion notification message indicating that the reception was successful to the data transmission / reception unit 116. The exchange completion data is received from the exchange completion data management device 21 (step S2806), and the process is terminated. In addition, even when a retransmission request is given from the device 11b to the device 11a, the device 11b may operate in the same manner.

  As described above, when each device cannot receive the desired data to the end, it makes a retransmission request to the counterpart device, so that it is possible to receive the desired data to the end.

  In the above description, the device 11b transmits the remaining data in response to the retransmission request. However, when the device 11b cannot communicate, the device 11a normally receives the remaining data. Therefore, the exchange completion notification indicating that the data could not be normally received is transmitted to the exchange completion data management device 21.

  In the embodiment in which the exchange completion data management device 21 creates the exchange completion data, when the device 11b resends the exchange target data in response to a retransmission request from the device 11b, the exchange completion data management device 21 converts the exchange completion data from the exchange completion data management device 21 again. Processing data and exchange completion data may be acquired to create post-conversion data. In this case, the device 11b may send the converted data from the beginning. The device 11a to which the converted data is sent from the beginning may discard the already received data.

(Third embodiment)
In the third embodiment of the present invention, a system that simplifies data exchange according to the exchange partner user will be described. Also in the third embodiment, the configuration of the entire system is the same as that of the first embodiment, so FIG. 1 is used.

  In the third embodiment, the device 11 stores in the data storage device 114 the exchange history with the counterpart device that has exchanged data so far. FIG. 29 is a diagram illustrating an example of a data configuration of an exchange history stored in the device 11. As shown in FIG. 29, the exchange history is calculated from the number of exchanges so far, the number of successful exchanges so far, the number of exchanges and the number of successes so far, corresponding to the device ID of the exchange partner device. Rate, the reception ratio of the data exchanged last, and the storage position of the finally received data (hereinafter referred to as the final data storage position). When data exchange with another device 11 is performed, the device 11 registers the data exchange result in the data storage device 114 as an exchange history.

  FIG. 30 is a flowchart showing the operation of the device 11a when the device 11b is requested to exchange data. First, the message processing unit 112 of the device 11a creates a data exchange message for the device 11b and causes the data transmission / reception unit 116 to transmit the message (step S3001). Next, the device 11a receives the ACK message from the device 11b, and recognizes the public data owned by the selected device 11a (step S3002).

  Next, the device 11a refers to the replacement history and determines a method for creating replacement completion data (step S3003). There are various methods for creating the exchange completion data. For example, “if the number of exchanges is 5 times or more and the success rate is 95%, the device 11a sends it directly to the device 11b without performing data conversion such as encryption”, “successful if the number of exchanges is 5 times or more When the number of times is 80% or more and less than 95%, the data is encrypted using an encryption key with a key length of 128 bits, and the decryption key corresponding to the encryption key is used as exchange completion data. ” If the success count is less than 80%, the data is encrypted using an encryption key with a key length of 1024 bits, and the decryption key corresponding to the encryption key is used as exchange completion data. In this case, a method of encrypting data using an encryption key having a key length of 512 bits and using a decryption key corresponding to the encryption key as exchange completion data is conceivable. That is, the higher the success rate of data, the shorter the key length of the encryption key, so that it is possible to save the time and effort required for decryption for a trusted counterpart device. For example, in the example of FIG. 29, data encryption is not performed for the device with the device ID “C0001”. The device with the device ID “C0002” is encrypted using an encryption key having a 512-bit key length. The device having the device ID “C0003” is encrypted using an encryption key having a key length of 1024 bits. The method for creating the exchange completion data is not limited to the above.

  Next, the device 11a creates post-conversion data and exchange completion data using the creation method determined in step S3003 (step S3004), and transmits the created exchange completion data to the exchange completion data management device 21 ( Step S3005), data exchange is started (step S3006), and the process is terminated.

  In this way, the exchange completion data can be created based on the exchange history with the device that has exchanged data so far, and the restoration process in the counterpart device can be simplified. Therefore, it is possible to quickly exchange with a reliable partner, and an easy-to-use system is provided. Furthermore, since conversion of data to be transmitted can be simplified based on an exchange history with a device that has exchanged data so far, data exchange with a reliable partner can be performed more quickly.

  In the above embodiment, the operation when the exchange completion data is created in the device has been described. Hereinafter, an operation when creating exchange completion data by the exchange completion data management apparatus will be described.

  FIG. 31 is a flowchart showing the operation of the device 11a when the exchange completion data is created by the exchange completion data management apparatus. The message processing unit 112 of the device 11a creates a data exchange message for the device 11b and causes the data transmission / reception unit 116 to transmit the message (step S3101). Next, the device 11a receives the ACK message from the device 11b, and recognizes the public data owned by the selected device 11a (step S3102).

  Next, the device 11a refers to the replacement history and determines a replacement processing method in the replacement completion data management device 21 (step S3103). Here, the exchange processing method is a method for converting data in the device 11a. For example, the device 11a refers to the exchange history, and determines the length of the encryption key to be used when encrypting data as the conversion process. In this case, the device 11a uses a short encryption key for a device having a high exchange success rate.

  Next, the device 11a notifies the exchange completion data management device 21 of information indicating the determined exchange processing method (step S3104). In response to this notification, the exchange completion data management device 21 creates exchange process data (for example, an encryption key) used in the designated conversion process method, and further, exchange completion data corresponding to the exchange process data. (For example, a decryption key) is created. Then, the exchange completion data management device 21 stores the created exchange completion data and transmits the exchange completion data to the device 11a.

  In response to this, the device 11a receives the exchange processing data (step S3105), creates converted data using the exchange processing data (step S3106), and starts data exchange with the device 11b.

  Note that, as shown in FIG. 29, the data reception ratio and final data storage location registered in the exchange history when the device 11a makes a retransmission request to the device 11b when the data cannot be received normally. Used for. In this case, it is assumed that the size of data to be transmitted in advance is exchanged between both devices at the start of data exchange. The device 11a notifies the device 11b of information related to the communication result indicating how far the data has been normally received from the data reception rate. In response to this, the device 11b recognizes the remaining portion that could not be transmitted normally and retransmits it to the device 11a. The device 11a stores the retransmitted data so that a part of the data stored in the collection data storage position is connected to the rest of the reproduced data.

  A hash value of data to be transmitted in advance at the start of data exchange may be exchanged between both devices. In this case, a device that wishes to exchange data obtains a hash value of the received data and determines whether the data has been received to the end. If the data has not been received to the end, the device that wishes to exchange data transmits a hash value of a part of the received data to the counterpart device. In response to this, the counterpart device retransmits the remaining data recognized from the hash value. By using the hash value in this way, it is possible to recognize whether or not the desired data has been received even if the data size has changed on the transmission path.

  The inter-device data exchange system according to the present invention and the devices used therefor, the exchange completion data management device and the program can prevent unfair exchange from occurring without increasing communication costs and server burdens. This is useful in a system for exchanging electronic data such as contents.

The block diagram which shows the whole structure of the data exchange system Sa between the apparatuses with a mediation server in the 1st Embodiment of this invention. The block diagram which shows the functional structure inside the apparatus 11 The figure which shows an example of the data structure of the data with which data ID and public data ID were linked | related The figure which shows an example of the data structure of the data corresponding to data ID of FIG. The figure which shows the data structure of the publication content information corresponding to data ID for publication of FIG. The block diagram which shows the detailed functional structure inside the data conversion part 111 The block diagram which shows the functional structure inside the exchange completion data management apparatus 21 The figure which shows an example of the data structure of a judgment table The figure which shows an example of the data structure of the exchange completion data corresponding to the exchange completion data ID of FIG. The block diagram which shows the detailed functional structure inside the exchange completion data transmission determination part 211 A block diagram showing an internal functional configuration of the public data management device 31 The figure which shows an example of the data structure of public list data The figure which shows an example of the data structure of the content information corresponding to public data ID of FIG. The sequence diagram which shows operation | movement of the apparatus 11 and the public data management apparatus 31 at the time of registering the content information regarding the data for public possession which the apparatus 11 has in the public data management apparatus 31 Sequence diagram showing operations of the public data management apparatus 31 and the device 11 when the public data management apparatus 31 receives a public data registration message Sequence diagram showing operation of device 11a when acquiring device ID Sequence diagram showing operations of public data management device 31 and device 11a when public data management device 31 receives a registered device ID acquisition message Sequence diagram showing operations of device 11a and device 11b until device 11a offers data exchange to device 11b and receives a response When the ACK message received by the device 11a from the device 11b includes the public data ID desired to be exchanged, the device 11a and the exchange completion until the exchange completion data management device 21 is offered an intermediary process and a response is received. Sequence diagram showing operation of data management device 21 Sequence diagram showing operations of the device 11a and the device 11b until the device 11a receives an ACK message from the exchange completion data management device 21 and starts exchanging data with the device 11b. Sequence diagram showing operations of the device 11a and the exchange completion data management device 21 from when the device 11a finishes communication with the device 11b until receiving an ACK message from the exchange completion data management device 21 Sequence diagram showing operation of device 11a after receiving ACK message from exchange completion data management device 21 Sequence diagram showing operation of device 11b when device 11b receives a data exchange message from device 11a Sequence diagram showing the operation of the exchange completion data management device 21 when the exchange completion data management device 21 receives the exchange completion data registration message from the devices 11a and 11b. Sequence diagram showing operation of device 11b when device 11b receives an exchange start message from device 11a Sequence diagram showing the operation of the exchange completion data management device 21 when the exchange completion data management device 21 receives the exchange completion notification message from the devices 11a and 11b The flowchart which shows operation | movement of the exchange completion data management apparatus 21 until it deletes exchange completion data. Sequence diagram showing operations of device 11a and device 11b when device 11a requests device 11b to resend exchange target data The figure which shows an example of the data structure of the exchange log | history stored in the apparatus 11 Flow chart showing the operation of the device 11a when requesting data exchange to the device 11b Flowchart showing the operation of the device 11a when creating exchange completion data in the exchange completion data management device

Explanation of symbols

Sa Inter-device data exchange system 11, 11a, 11b Device 21 Exchange completion data management device 31 Public data management device 41 Transmission path 111 Data conversion unit 112, 212, 311 Message processing unit 113, 213, 312 Storage device control unit 114, 214 , 313 Data storage device 115 User input / output unit 116, 215, 314 Data transmission / reception unit 211 Exchange completion data transmission determination unit 1111 Pre-conversion data conversion processing unit 1112 Exchange completion data creation unit 1113 Post-conversion data conversion processing unit 1114, 2113 Request determination Unit 2111 determination table reference unit 2112 determination table creation unit

Claims (29)

A system for exchanging data between devices connected via a communication medium,
A first device that possesses at least one exchangeable data and desires to exchange data with another device;
A second device possessing data desired by the first device;
In order to play back data acquired by the first device after the first and second devices have completed data exchange and are connected to the first and second devices via the communication medium An exchange completion data management device for managing first exchange completion data, which is necessary data, and second exchange completion data, which is data necessary for reproducing data acquired by the second device; ,
The exchange completion data management device
Only when both the first and second devices have successfully received the desired data, the first exchange completion data is transmitted to the first device, and the second exchange completion data is sent to the first device. A data exchange system between devices, including exchange completion data transmission means for transmitting to two devices. The first device is:
First exchange completion data creating means for creating the second exchange completion data;
First exchange completion data transmission means for transmitting the second exchange completion data created by the first exchange completion data creation means to the exchange completion data management device;
The second device is:
Second exchange completion data creating means for creating the first exchange completion data;
Second exchange completion data transmitting means for transmitting the first exchange completion data created by the second exchange completion data creating means to the exchange completion data management device;
The exchange completion data management device further includes:
2. The apparatus according to claim 1, further comprising exchange completion data management means for managing the first and second exchange completion data transmitted from the exchange completion data transmission means so that a transmission source device can be identified. Data exchange system between devices. The first device further includes:
First data conversion means for converting data owned by the device into data that can be normally reproduced only by using the second exchange completion data;
First data restoration means for restoring data received from the second device to data that can be normally reproduced using the first exchange completion data;
The second device further includes:
Second data conversion means for converting data owned by the device into data that can be normally reproduced only by using the first exchange completion data;
3. The device-to-device device according to claim 2, further comprising: a second data restoring unit that restores data received from the first device to data that can be normally reproduced using the second exchange completion data. Data exchange system. The first device further includes:
Including first exchange completion data creation requesting means for requesting the exchange completion data management device to create the second exchange completion data;
The second device further includes:
Second exchange completion data creation requesting means for requesting the exchange completion data management device to create the first exchange completion data;
The exchange completion data management device further includes:
Exchange completion data creation means for creating the first and second exchange completion data in response to requests from the first and second exchange completion data creation request means;
2. The inter-device data according to claim 1, further comprising: an exchange completion data management unit that manages the first and second exchange completion data created by the exchange completion data creation unit so that a requested device can be identified. Exchange system. Each of the first and second devices further includes:
Data conversion means for converting the first data owned by the own device into second data that can be normally reproduced only by using the exchange completion data;
Data restoration means for restoring data received from a data exchange partner device to data that can be normally reproduced using the exchange completion data transmitted from the exchange completion data transmission means,
The exchange completion data management device
By using the first and second exchange completion data, the first and second conversion processing data for converting the first data so that the second data can be reproduced normally is created. A conversion processing data creation and transmission means for transmitting the first conversion processing data to the second device and transmitting the second conversion processing data to the first device;
The data conversion means of the first device converts the first data into second data using the second conversion processing data from the conversion processing data transmission means,
The data conversion means of the second device converts the first data into second data using the first conversion processing data from the conversion processing data transmission means. Item 5. The inter-device data exchange system according to Item 4. The first conversion processing data is a first encryption key,
The first exchange completion data is a first decryption key corresponding to the first encryption key;
The second exchange processing data is a second encryption key,
6. The inter-device data exchange system according to claim 5, wherein the second exchange completion data is a second decryption key corresponding to the second encryption key. Each of the first and second devices further includes:
Including communication result notification means for notifying the exchange completion data management device of information indicating a communication result when communication with the data exchange partner device is terminated;
The exchange completion data transmission means is configured so that both the first and second devices normally transmit desired data based on information indicating the communication result from the communication result notification means of the first and second devices. The inter-device data exchange system according to claim 1, wherein it is determined whether or not reception is possible. The information indicating the communication result is information indicating whether or not the desired data has been successfully received,
8. The apparatus according to claim 7 , wherein the exchange completion data transmitting unit transmits the exchange completion data when information indicating that the exchange completion data has been normally received from the first and second apparatuses is received. Inter-data exchange system. The first exchange completion data is a decryption key for decrypting data given to the first device by the second device,
The inter-device data exchange according to claim 1, wherein the second exchange completion data is a decryption key for decrypting data given to the second device by the first device. system.   The said 1st and 2nd apparatus further contains the resending request | requirement means which requests | requires resending of data with respect to the apparatus of the other party of exchange, when desired data cannot be received completely. Inter-device data exchange system. A device for exchanging the desired data and the data owned by the own device with another device that owns the desired data,
Exchange completion data creating means for creating first exchange completion data which is data necessary for reproducing data owned by the own device;
Exchange completion data registration means for registering the first exchange completion data created by the exchange completion data creation means in an exchange completion data management device that manages exchange completion data;
When the communication with the other device is completed, the exchange completion data acquisition for acquiring the second exchange completion data, which is data necessary for reproducing the data acquired from the other device, from the exchange completion data management device Means, including means. Further, data conversion means for converting data owned by the device into data that can be normally reproduced only by using the first exchange completion data;
12. Data restoration means for restoring the data obtained from the other device to data that can be normally reproduced using the second exchange completion data obtained by the exchange completion data obtaining means. Equipment described in. Furthermore, it comprises an exchange history storage means for storing a past exchange history with the data exchange partner device,
The data conversion means changes a data conversion method based on the exchange history,
The exchange completion data generation means, on the basis of the exchange history, and changes the method of creating exchange completion data, equipment according to claim 12.   The device according to claim 11, further comprising: a retransmission request means for requesting retransmission of data to an exchange partner device when desired data cannot be completely received. A device for exchanging the desired data and the data owned by the own device with another device that owns the desired data,
Exchange completion data creation request means for requesting the exchange completion data management device that manages the exchange completion data to create the first exchange completion data that is data necessary for reproducing the data owned by the own device;
When the communication with the other device is completed, the exchange completion data acquisition that acquires the second exchange completion data, which is data necessary for reproducing the data acquired from the other device, from the exchange completion data management device Means, including means. Further, a conversion process for converting the owned data so that the data owned by the own device can be normally reproduced by using the first exchange completed data sent from the exchange completed data management device. Conversion processing data receiving means for receiving data;
Data conversion means for converting data owned by the device itself using the conversion processing data received by the conversion processing data receiving means;
16. Data restoration means for restoring the data obtained from the other device to data that can be normally reproduced using the second exchange completion data obtained by the exchange completion data obtaining means. Equipment described in. Further, an exchange history storage means for storing a past exchange history with the device of the data exchange partner,
Conversion method notification means for notifying the exchange completion data management device of a conversion method used by the data conversion means based on the exchange history,
The data conversion means converts data owned by the device itself using conversion processing data using the specified conversion method sent from the exchange completion data management device. The equipment described.   The device according to claim 15, further comprising: a retransmission requesting unit that requests retransmission of data to the exchange partner device when desired data cannot be completely received. An apparatus used in a system for exchanging data between devices connected via a communication medium,
Exchange completion data management means for managing exchange completion data necessary for reproducing data exchanged between the first device and the second device;
Only when both the first and second devices have successfully received the desired data, exchange completion data necessary for reproducing the data acquired by the first device is transmitted to the first device. And an exchange completion data transmitting means for sending exchange completion data necessary for reproducing the data acquired by the second device to the second device. Furthermore, an exchange completion data creating means for creating the exchange completion data in response to requests from the first and second devices,
20. The exchange completion data management device according to claim 19, further comprising exchange completion data management means for managing the exchange completion data created by the exchange completion data creation means so that a requested device can be identified.   Furthermore, by using the exchange completion data created by the exchange completion data creating means to create conversion processing data for allowing the first and second devices to normally reproduce the data after exchange, 21. The exchange completion data management apparatus according to claim 20, further comprising conversion processing data creation and transmission means for transmitting to the first and second devices.   The exchange completion data transmission means determines whether or not both the first and second devices have successfully received the desired data based on information indicating communication results from the first and second devices. 20. The exchange completion data management apparatus according to claim 19, wherein the exchange completion data management apparatus is determined. The information indicating the communication result is information indicating whether or not the desired data has been successfully received,
The exchange according to claim 22, wherein the exchange completion data transmitting means transmits exchange completion data when receiving information indicating that the exchange completion data has been normally received from the first and second devices. Completion data management device.   20. The exchange completion data management apparatus according to claim 19, further comprising exchange completion data deleting means for deleting managed exchange completion data when a predetermined condition is satisfied.   When the exchange completion data transmitted by the exchange completion data transmission unit is normally received by the first and second devices as the predetermined condition, the exchange completion data deletion unit performs the first and second operations. The exchange completion data management apparatus according to claim 24, wherein the exchange completion data transmitted to the device is deleted.   The exchange completion data deleting means is registered by the first and second devices when receiving a notification that the desired data could not be normally received from any one device as the predetermined condition. The exchange completion data management apparatus according to claim 24, wherein the exchange completion data is deleted. A program for causing a computer device to exchange the desired data and the data owned by itself with another computer device that owns the desired data,
Causing the computer device to create first exchange completion data, which is data necessary for reproducing the data owned by itself;
Registering the created first exchange completion data in the computer device with an exchange completion data management device that manages the exchange completion data;
When communication with the other computer device is completed, second exchange completion data, which is data necessary for reproducing data acquired from the other computer device, is transferred from the exchange completion data management device to the computer device. A program comprising the steps of obtaining. A program for causing a computer device to exchange the desired data and the data owned by itself with another computer device that owns the desired data,
Causing the computer apparatus to request the exchange completion data management apparatus that manages the exchange completion data to create the first exchange completion data that is data necessary for reproducing the data owned by itself;
When communication with the other computer apparatus is completed, second exchange completion data, which is data necessary for reproducing data acquired from the other computer apparatus, is transferred from the exchange completion data management apparatus to the computer apparatus. A program comprising the steps of obtaining. A computer device used in a system for exchanging data between computer devices connected via a communication medium,
Exchange completion data management means for managing exchange completion data necessary for reproducing data exchanged between the first computer apparatus and the second computer apparatus; and
Only when both the first computer apparatus and the second computer apparatus have successfully received the desired data, exchange completion data necessary for reproducing the data acquired by the first computer apparatus is transmitted to the first computer. A program for functioning as exchange completion data transmission means for transmitting to the second computer apparatus the exchange completion data necessary for transmitting to the apparatus and reproducing the data acquired by the second computer apparatus.

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