JP2003122635A - Access right control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an access right control system capable of performing desired access right control in client equipment in a peer-to-peer file exchange system. SOLUTION: An access right control system is provided with a server 11, an access right managing data base 12, first and second client equipment 13 and 15, and data storage devices 14 and 16. The first and second client equipment 13 and 15 share a peer-to-peer file exchange system. The first and second client equipment 13 and 15 are constituted so as to be accessible to the server 11. The access right managing data base 12 stores an access right management list. When data are requested from the second client equipment 15, the first client equipment 13 inquires the server 11 about the access right, and the server 11 determines the access right by using the access right management list.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an access right control system for exchanging data in a peer-to-peer format in a network.

[0002]

2. Description of the Related Art In recent years, peer-to-peer computing has attracted attention. Peer-to-peer computing enables sharing of computer resources (CPU power and hard disk space) and various services (messages, file exchange systems, etc.) by directly communicating between devices connected by a network. It is a technology that allows even collaborative work between them. In this peer-to-peer file exchange system,
Devices (client devices) owned by the end users can directly communicate with each other to exchange files managed by the devices.

Whether or not a file managed by a client device in the peer-to-peer type file exchange system can be accessed by others (hereinafter referred to as an access right) is determined by the client device itself.
For example, the access destination (data provider) client device requests a password from the access source (data provider) client device, and only when the correct password is sent from the access source client device, The access right is controlled by allowing access to the file managed by the client device of the access destination. Further, as complicated access right control performed by the access destination client device, there is access right control by an access date and time or an identifier for identifying the access source client device, and further, for each file managed by the access destination client device, It is conceivable to set unique control information for each.

[0004]

Such complicated access right control is easy to realize when the client device of the access destination is composed of a personal computer or the like having a high processing capability. However, when the client device of the access destination is a consumer device having a limited processing capability, it is very difficult to realize the complicated access right control as described above. In addition, unlike personal computers, it is very difficult to replace the software stored in consumer devices with limited processing capacity after purchase, and the access right control method described above was added later. Or it cannot be modified.

[0005] On the other hand, a server, which is communicatively connected to the peer-to-peer file exchange system, manages files managed by client devices provided in the system as a list. The file name managed by the client device and the client device are described in the list managed by the server, and the client device provided in the same system refers to the list to obtain a desired list. The existence of the file and the client device that manages it are known. However, the above-mentioned server does not have the function of performing the above-mentioned access right control, and finally, the same access right control as that described above is performed by the client device of the access destination managing the desired file. Has been done.

Therefore, an object of the present invention is to provide an access right control system capable of executing desired access right control in a client device in a peer-to-peer type file exchange system.

[0007]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, the present invention has the following features. A first aspect of the present invention is an access right control system for determining an access right indicating permission / inhibition of access when a client device owned by an end user is directly requested by another device to transmit data. A communication device that is communicatively connected to the client device and that manages an access right management list in which the access right of the client device is described in advance. When the client device is requested to send data directly by another device, the client device includes an access permission determination unit that determines the access permission and sends back a determination result to the access permission determination unit. Results of inquiries by the access permission / inquiry part to be inquired and the access permission / inquiry part If the access judging unit the returned determination result from is accessible, and a data transmission unit which directly transmits the requested data to the other devices.

According to the first aspect of the present invention, by inquiring the access right from the client device which is the source of the data, the control of the access right at the time of performing the peer-to-peer data exchange is performed on the side of the server having a high processing capability. Therefore, even complicated access right control can be appropriately processed. While realizing such complicated access right control, the data itself to be exchanged can be exchanged without directly putting the load on the server on the network band by directly transmitting / receiving between the client devices. is there. Even if the client device is composed of a consumer device with a limited processing capacity, since the complicated access right control is processed by the server, it is possible to perform peer-to-peer data exchange by a consumer device with a restricted processing capability. On the other hand, the above-mentioned complicated access right control can be easily added.

A second invention is an invention subordinate to the first invention, and the access right management list managed by the server indicates an access right indicating an accessible device for each data managed by each client device. Is described, the access permission / inquiry unit makes an inquiry to the access permission / inhibition determination unit for each data requested to be transmitted, and the access permission / inhibition determination unit responds to the inquiry for each data by the access permission / inhibition unit. The right is judged and the judgment result is returned.

According to the second invention, it becomes possible to set an access right for each data managed by each client device.

A third aspect of the present invention is an aspect according to the second aspect of the present invention, further, in the access right management list managed by the server, a time condition indicating an accessible time is described for each data. The permission / inhibition determination unit refers to the time condition according to the current time inquired from the access permission / inquiry unit, and determines the access right for each data.

According to the third invention, it becomes possible to set an access right for each data managed by each client device, on the condition of the accessible time.

A fourth invention is an invention according to the second invention, and further, in the access right management list managed by the server, the number of times condition indicating the number of times of access is described for each data. The permission / prohibition determination unit refers to the number-of-times condition according to the number of inquiries from the access permission / inquiry unit, and determines the access right for each data.

According to the fourth invention, it is possible to set an access right for each data managed by each client device, on the condition that the number of times the client device can be accessed.

A fifth aspect of the invention is an invention dependent on the second aspect of the invention, and further, in the access right management list managed by the server, a duplication condition indicating a limitation regarding duplication of the data provided for each data. Is described, the access permission / inhibition determination unit determines the access right according to the inquiry for each data from the access permission / inquiry unit, and returns the duplication condition together with the determination result. If the result of the determination is that the data is accessible, the requested data is added with a copy condition and directly transmitted to another device.

According to the fifth aspect of the invention, it is possible to add a restriction on copying after data acquisition for each data managed by each client device.

A sixth invention is an invention according to the first invention, characterized in that the server is communicably connected to the client device via another proxy.

According to the sixth aspect of the present invention, even if the client device of the provider who inquires about the access right cannot directly communicate with the server, the access right can be inquired via another proxy, and the peer-to-peer method is possible. The access right at the time of exchanging data can be controlled on the side of the server having high processing capability.

A seventh invention is an invention according to the first invention, wherein the access permission / inhibition inquiry unit inquires of the access permission / inhibition determination unit about an access right to the request when data transmission is requested by another device. , A first certificate for certifying that the device is a client device and a second certificate for certifying the other device are added to the access permission determination unit, and the access permission determination unit After authenticating the inquiry from the access permission inquiry unit using the first and second certificates, the access right is judged and the judgment result is returned.

According to the seventh invention, the server can authenticate the first and second certificates and confirm that the communication is from the correct client device.

An eighth invention is an invention subordinate to the seventh invention, wherein the certificate is X.509. 509 is used.

According to the eighth invention, the server is Fifty
It is possible to easily and surely confirm that the communication is from the correct client device by using the 9-system certificate.

According to a ninth aspect of the present invention, when the second client device requests direct data transmission to the first client device owned by the end user, the access right indicating whether or not the access is permitted is determined. And a server which is communicably connected to at least a second client device and manages an access right management list in which access rights of at least the first and second client devices are described in advance. The server includes an access permission / inhibition determination unit that determines the access right by referring to the access right management list in response to the inquiry about the access right and returns the determination result, and the second client device is the first client device. When requesting direct data transmission to a user, the access right to the request is determined If the result of the inquiry made by the access permission inquiry unit and the access permission inquiry unit is that the determination result returned from the access permission determination unit is accessible, the determination result is directly added to the first client device. And a data requesting unit for requesting specific data transmission, wherein the first client device is
When the determination result transmitted from the data request unit is accessible, the data transmission unit includes a data transmission unit that directly transmits the data requested by the data request unit to the second client device, and the second client device includes: The data receiving unit further includes a data receiving unit that directly receives the data transmitted from the data transmitting unit in response to a request from the data requesting unit.

According to the ninth aspect of the invention, by inquiring the access right from the second client device, which is the data providing destination, the control of the access right at the time of performing the peer-to-peer data exchange is controlled by the server side having a high processing capability. Therefore, even complicated access right control can be appropriately processed. While realizing such complicated access right control, the data itself to be exchanged can be exchanged without directly putting the load on the server on the network band by directly transmitting / receiving between the client devices. is there. Even if the client device is composed of a consumer device with a limited processing capacity, since the complicated access right control is processed by the server, it is possible to perform peer-to-peer data exchange by a consumer device with a restricted processing capability. On the other hand, the above-mentioned complicated access right control can be easily added.

A tenth invention is an invention subordinate to the ninth invention, wherein the access right management list managed by the server indicates an access right indicating an accessible device for each data managed by each client device. Is described, the access permission / inquiry section makes an inquiry to the access permission / inhibition determination section for each data requesting data transmission, and the access permission / inhibition determination section responds to the access right And return the judgment result.

An eleventh invention is an invention subordinate to the tenth invention, and further, a time condition indicating an accessible time is described for each data in the access right management list managed by the server. The permission / prohibition determination unit refers to the time condition according to the current time inquired from the access permission / inquiry unit, and determines the access right for each data.

A twelfth invention is an invention dependent on the tenth invention, and further, in the access right management list managed by the server, the number condition indicating the number of times of access is described for each data, The permission / prohibition determination unit refers to the number-of-times condition according to the number of inquiries from the access permission / inquiry unit, and determines the access right for each data.

[0028] A thirteenth invention is an invention subordinate to the tenth invention, and further, in the access right management list managed by the server, a duplication condition indicating a limitation relating to duplication of the data provided for each data. Is described, the access permission / inhibition determination unit determines the access right in response to an inquiry for each data by the access permission / inquiry unit, and returns a replication condition together with the determination result. If the judgment result is accessible,
Direct data transmission is requested to the first client device together with the determination result and the copy condition, and the data transmission unit is requested by the data request unit when the determination result transmitted from the data request unit is accessible. The duplication condition is directly transmitted together with the data to the data receiving unit, and the data receiving unit directly receives the data transmitted from the data transmitting unit, and the duplication condition of the data restricts subsequent duplication. .

According to the thirteenth aspect, even when the client device to which the data is provided inquires the server about the access right, a restriction regarding copying after data acquisition is added to each data managed by each client device. It becomes possible.

A fourteenth invention is an invention subordinate to the ninth invention, characterized in that the server is communicably connected to the second client device via another proxy.

According to the fourteenth aspect, even if the second client device, which is the destination of the inquiry for the access right, cannot directly communicate with the server, the access right can be inquired through another proxy. It is possible to control the access right when exchanging data peer-to-peer on the side of the server having high processing capability.

A fifteenth invention is a invention subordinate to the ninth invention, wherein the access permission / inquiry section accesses the access right to the request in order to request the data transmission to the first client device. When making an inquiry to the permission determination unit, a certificate for certifying that the device is the second client device is added to the access permission determination unit, and the access permission determination unit uses the certificate to access from the access permission determination unit. After authenticating the inquiry, the access right is judged and the judgment result is returned.

According to the fifteenth aspect, the server can authenticate the certificate and confirm that the communication is from the second client device.

A sixteenth invention is an invention subordinate to the fifteenth invention, and further, the access permission / inhibition determination unit returns a response with a signature for certifying that the determination is made by the server. If the determination result returned from the access permission / inhibition determination unit is accessible, the data request unit requests the first client device for direct data transmission together with the determination result with the signature and the certificate, The data transmission unit authenticates using the signature of the judgment result transmitted from the data request unit, and if the judgment result is accessible, the data transmission unit directly transmits the data requested by the data request unit and the duplication condition to the data reception unit. To send.

According to the sixteenth invention, the signature can prevent the result of the determination of the access right from being tampered with in the course of communication, and the result can be certainly determined by the server in the first client device. Can be judged.

A seventeenth invention is an invention subordinate to the fifteenth invention, wherein the certificate is X.509. 509 is used.

An eighteenth aspect of the present invention is a server which, when a plurality of client devices owned by an end user directly send and receive data managed by the client devices, determines an access right indicating whether or not the data can be accessed. hand,
By referring to the access right management list in the access right management unit for the access right management unit that manages the access right management list in which the access right of the client device is described in advance and the inquiry about the access right transmitted from the client device. , And an access permission determination unit that returns the access right and returns the determination result to the client device that made the inquiry.

According to the eighteenth aspect of the present invention, by controlling the access right at the time of exchanging data peer-to-peer with a server having a high processing capacity, the access right is inquired from the client device for exchanging data.
It is possible to configure a server that can appropriately process even complicated access right control.

In a nineteenth aspect of the present invention, when a direct data transmission is requested from another device, an access right indicating permission / prohibition of the data is managed in an access right management list in which the access right is described in advance for each device. A client device owned by an end user that allows a server that can communicate with it to determine,
When a direct data transmission is requested from another device, the access permission inquiry unit that inquires the access right to the request and the access permission inquiry unit, and the result of the inquiry returned from the server is accessible. In this case, the data transmission unit that directly transmits data in response to a request from another device is included.

According to the nineteenth aspect of the invention, by controlling the access right at the time of performing the peer-to-peer data exchange with the server having a high processing capability, the access right is inquired from the client device requested to transmit the data. Therefore, it is possible to configure a client device capable of appropriately processing even complicated access right control. Even if the client device of the providing source is a consumer device with a limited processing capability, the above complicated access right control is processed by the server. The above-mentioned complicated access right control can be easily added to the data exchange.

The twentieth aspect of the present invention is a communication for managing an access right management list in which the access right indicating permission / inhibition of the access right is previously described for each device when a direct data transmission is requested to another device. A client device owned by an end user that allows a possible server to determine the access right to the server when requesting direct data transmission to another device. When the determination result returned from the server is accessible as a result of the inquiry by the unit, the data request unit that adds the determination result to another device and requests direct data transmission is included.

According to the twentieth aspect of the present invention, by controlling the access right at the time of exchanging data peer-to-peer with the server having high processing capability, the access right is inquired from the client device requesting the data transmission. It is possible to configure a client device that can appropriately process even complicated access right control. Even when the client device of the providing source and the client device of the providing destination are configured by consumer devices with limited processing capability, the complicated access right control is processed by the server. It is possible to easily perform the above-mentioned complicated access right control for peer-to-peer data exchange.

A twenty-first aspect of the present invention is a client device owned by an end user that directly transmits data when requested by another device, and a request for direct data transmission from another device and the request. If the judgment result received by the receiving unit receives the judgment result of the access right indicating whether or not the data transmission is added and transmitted in addition to the request, and the judgment result received by the receiving unit is accessible, the data requested by another device The data transmission unit for directly transmitting

According to the twenty-first aspect of the present invention, the result of the determination of the access right at the time of exchanging data on a peer-to-peer basis is transmitted together with the request for data transmission, so that the client device requested to transmit the data has the result of the determination. Since it is possible to determine whether or not access is possible based on the above, it is possible to configure a client device that can appropriately process even complicated access right control. Even if the client device of the providing source is a consumer device with limited processing capability, the client device of the providing source does not need to control access rights, and thus peer-to-peer with a consumer device with limited processing capability. It is possible to easily perform complicated access right control for the data exchange in the above.

A twenty-second aspect of the invention is an invention dependent on the twenty-first aspect of the invention, wherein the determination result is added with a signature for proving that the device has determined the access right, and data transmission The unit evaluates the validity of the determination result by authenticating the signature of the determination result, and when the determination result is valid and accessible, the unit directly transmits the data requested by the other device.

According to the twenty-second aspect of the invention, the result of determination of the access right at the time of performing the peer-to-peer data exchange, which is transmitted together with the request for the data transmission, is prevented from being tampered with by the signature during the communication. Therefore, it is possible to reliably authenticate the authenticity of the client device of the provider.

In the twenty-third aspect of the present invention, when a client device owned by an end user is directly requested by another device to transmit data, an access right indicating whether or not the device can be accessed can be communicated with the client device. A method of controlling access right for a connected server, comprising: an access right management step of managing an access right management list in which access rights of client devices are described in advance; and a client device directly from another device. Access request for inquiring the access right to the request from the client device to the server when a specific data transmission is requested, and the access right managed in the access right management step for the inquiry in the access permission inquiry step By referring to the management list If the server determines the access right and returns the determination result to the client device, and if the determination result returned by the access permission determination step is accessible, the requested data is transferred from the client device to another device. And a data transmission step of directly transmitting the data to the user.

According to the twenty-third aspect, the access right is controlled on the side of the server having a high processing capability when the data is exchanged peer-to-peer by inquiring the access right from the client device which is the source of the data. Therefore, even complicated access right control can be appropriately processed. While realizing such complicated access right control, the data itself to be exchanged can be exchanged without directly putting the load on the server on the network band by directly transmitting / receiving between the client devices. is there. In addition, even if the client device is a consumer device with limited processing capability,
Since the above complicated access right control is processed by the server,
It is possible to easily perform peer-to-peer data exchange by a consumer device having a limited processing capacity by adding the above-mentioned complicated access right control.

In the twenty-fourth aspect, when the second client device requests direct data transmission to the first client device owned by the end user, the access right indicating whether or not the second client device can access the data is given. A method of controlling access right for a server communicatively connected to a second client device, wherein the server manages an access right management list in which access rights of at least first and second client devices are described in advance. And an access permission inquiry step of inquiring the access right to the request from the second client device to the server when the second client device requests the first client device for direct data transmission. Access to inquiries by the access permission inquiry step By referring to the access right management list managed in the management step, the access right is judged by the server and the judgment result is returned to the second client device. If the determination result is accessible, a data request step of adding the determination result to the first client device and requesting direct data transmission, and if the determination result transmitted by the data request step is accessible, A data transmission step of directly transmitting the data requested by the data request step to the second client device, and a data transmission step of directly transmitting the data transmitted from the first client device by the data transmission step to the second client device. And a step of receiving data.

According to the twenty-fourth aspect of the present invention, by inquiring the access right from the second client device, which is the data supply destination, the access right is controlled at the time of performing the peer-to-peer data exchange on the server side having a high processing capability. Therefore, even complicated access right control can be appropriately processed. While realizing such complicated access right control, the data itself to be exchanged is
By directly transmitting and receiving between the client devices, it is possible to exchange data without imposing a load on the server on the network band. Even if the client device is composed of a consumer device with a limited processing capacity, since the complicated access right control is processed by the server, it is possible to perform peer-to-peer data exchange by a consumer device with a restricted processing capability. On the other hand, the above-mentioned complicated access right control can be easily added.

A twenty-fifth aspect of the invention is such that, when client devices owned by end users directly transmit and receive data managed by the client devices, an access right indicating whether or not the data can be accessed can be communicated with the client devices. An access right management step, which is a recording medium readable by the server in which an access right control program for allowing a connected server to judge is recorded, and which manages an access right management list in which access rights of client devices are described in advance, When a client device directly sends / receives data, the client device refers to the access right management list managed in the access right management step in response to an inquiry about the access right from the client device to the server. By determining the access right, The results and an access permission determination step of replying to said client device.

According to the twenty-fifth aspect of the present invention, by controlling the access right at the time of performing the peer-to-peer data exchange by the server having a high processing capacity, the access right is inquired from the client device for exchanging the data.
Even a complicated access right control can be processed appropriately.

In the twenty-sixth aspect, when a direct data transmission is requested from another device, an access right indicating permission / prohibition of access is managed in an access right management list in which the access right is described in advance for each device. A recording medium readable by a client device owned by an end user, which stores an access right control program that causes a communicable server to judge, and when the client device is requested to send data directly from another device, If the result of the inquiry in the access permission inquiry step for inquiring the access right to the request to the server and the access permission inquiry step is that the judgment result returned from the server is accessable, the requested data is sent from the client device to another device. And a data transmitting step of directly transmitting the data.

According to the twenty-sixth aspect, by controlling the access right at the time of performing the peer-to-peer data exchange by the server having a high processing capability, the access right is inquired from the client device requested to transmit the data. Therefore, even complicated access right control can be appropriately processed. Even if the client device of the providing source is a consumer device with a limited processing capability, the above complicated access right control is processed by the server. The above-mentioned complicated access right control can be easily added to the data exchange.

A twenty-seventh aspect of the invention is a communication for managing an access right management list in which an access right indicating permission / inhibition of the access right is previously described when requesting a direct data transmission to another device. A recording medium readable by a client device owned by an end user, which stores an access right control program that allows a server to judge, and an access right to the request when directly requesting data transmission to another device. The access permission inquiry step and the access permission inquiry step, and if the determination result returned from the server is accessible, the determination result is added to another device and the data is transmitted directly. And a data request step for requesting.

According to the twenty-seventh aspect of the present invention, by controlling the access right at the time of performing the peer-to-peer data exchange by the server having high processing capability, the access right is inquired from the client device requesting the data transmission, Even a complicated access right control can be processed appropriately. Even when the client device of the providing source and the client device of the providing destination are configured by consumer devices with limited processing capability, the complicated access right control is processed by the server. It is possible to easily perform the above-mentioned complicated access right control for peer-to-peer data exchange.

[0057]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) With reference to FIG. 1, an overall configuration of an access right control system according to a first embodiment of the present invention will be described. In FIG. 1, the access right control system includes a server 11, an access right management database 12, a first client device 13,
A data storage device 14, a second client device 15, and a data storage device 16 are provided. First and second
The client devices 13 and 15 are devices equipped with a CPU owned by the end user, and form peer-to-peer computing that directly communicates with each other, and form a peer-to-peer type file exchange system. The server 11 is communicatively connected to a client device arranged in the peer-to-peer file exchange system, and at least the first client device 13 is configured to be accessible to the server 11. There is. The data storage devices 14 and 16 include first and second client devices 13 and 15 respectively.
It is a storage device that stores files and the like managed by. The access right management database 12 is a storage device that stores an access right management list, which will be described later, managed by the server 11.

In the description of the embodiment, in order to simplify the description, the second client device 15 provides the desired file stored in the data storage device 14 managed by the first client device 13. Assuming a case of accessing for receiving, the first client device 13 is a client device of an access destination (hereinafter, referred to as a provider), and the second client device 15 is an access source (hereinafter, referred to as a client device).
The client device will be described as a "providing party"). Further, in the access right control system, 2
It is possible to deploy more than one client device, but here only the client device related to the access of the file will be described.

Next, the internal structure of the server 11 will be described with reference to FIG. 2. FIG. 2 is a functional block diagram showing the internal configuration of the server 11. In FIG. 2, the server 1
1 includes an access permission / inhibition determination unit 111, a database control unit 112, and an inter-client communication unit 113. The inter-client communication unit 113 uses a protocol such as TCP / IP and performs communication between the first client device 13 and the server 11. Database control unit 11
2 controls data stored in the access right management database 12. For example, when the database control unit 112 is requested by the access permission / prohibition determination unit 111 for the data stored in the access right management database 12, the database control unit 112 searches the data in the access right management database 12 in response to the request, or The data of is updated. Further, the database control unit 112 adds or deletes data in the access right management database 12 in response to a request from the client device instructed via the inter-client communication unit 113. The access permission / inhibition determination unit 111 refers to the access right management list of the access right management database 12 from the content when the access right determination is requested from the later-described first client device 13 via the inter-client communication unit 113. The access right determination result is returned to the inter-client communication unit 113. If it is determined that the access right management list needs to be updated, the database control unit 112 is instructed to update the access right management list.

Next, the internal configuration of the first client device 13 will be described with reference to FIG. Note that FIG.
3 is a functional block diagram showing an internal configuration of the first client device 13. FIG. In FIG. 3, the first client device 13 includes an inter-server communication unit 131, an access permission inquiry unit 132, a data transmission unit 133, an inter-client communication unit 134, and a storage device control unit 135. The inter-server communication unit 131 uses a protocol such as TCP / IP and uses the first client device 13 and the server 1.
It communicates with 1. In addition, the inter-client communication unit 1
34 uses a protocol such as TCP / IP to perform communication between the first client device 13 and the second client device 15. When the second client device 15 requests a list of data stored in the data storage device 14 via the inter-client communication unit 134, the data transmission unit 133 sends a data storage device via the storage device control unit 135. A list of data stored in 14 is generated, and the data list is provided to the second client device 15. In addition, when the data transmission unit 133 is notified by the server 11 that access is possible, the storage device control unit 13
The requested data is acquired from the data storage device 14 via 5, and this data is transmitted to the second client device 15 by controlling the inter-client communication unit 134. When accepting a data request from the second client device 15, the access permission / inquiry unit 132 makes an inquiry to the server 11 via the inter-server communication unit 131 in order to determine whether or not the data can be provided. Further, the first client device 13 has a unique identifier, and this identifier is stored in an identifier storage unit (not shown). The above-mentioned identifier is the first client device 13
The information peculiar to the CPU provided in the above may be used, or the IP address may be used.

Next, the internal configuration of the second client device 15 will be described with reference to FIG. Note that FIG.
FIG. 3 is a functional block diagram showing the internal configuration of the second client device 15. In FIG. 4, the second client device 15 includes an inter-client communication unit 151, a data request unit 152, a data receiving unit 153, and a storage device control unit 15.
4, a display device 155, and an input device 156. The inter-client communication unit 151 uses a protocol such as TCP / IP and performs communication between the first client device 13 and the second client device 15. The display device 155 prompts the user of the second client device 15 to select from the data list by displaying the data list received from the first client device 13 via the inter-client communication unit 151, for example. The input device 156 selects desired data from the data list by a user operation. The data request unit 152 performs communication for data request to the first client device 13 via the inter-client communication unit 151 in order to acquire the data selected by the user. Data receiving unit 153
When the data request is permitted, the storage device control unit 154 controls the data storage device 16 to store the data from the first client device 13 via the inter-client communication unit 151. Device 1
Store in 6. In addition, the second client device 15
It has a unique identifier, and this identifier is stored in an identifier storage unit (not shown). The above identifier is
The information unique to the CPU provided in the second client device 15 may be used, or the IP address may be used.

In this embodiment, the first and second
It has been described that the client devices 13 and 15 have different internal configurations. Such a difference is
This is because it is assumed that the first client device 13 is the data provider and the second client device 15 is the data provider as described above. Therefore, when it is convenient for the first and second client devices 13 and 15 to be both the source and the destination, it is sufficient to provide each client device with the function of both client devices. .

Next, the overall processing of the access right control system will be described with reference to FIG. Note that FIG. 5 is a flow chart showing the operations performed by the server 11, the first and second client devices 13 and 15 which constitute the access right control system. Regarding the entire processing of the access right control system described here as well, it is assumed that the first client device 13 is the data provider and the second client device 15 is the data provider, and the second client device 15 A case where desired data stored in the data storage device 14 managed by the first client device 13 is acquired will be described. The processing operation of this access right control system is stored in the storage area provided in each device in the server 11, the first and second client devices 13 and 15, and the access right control program corresponding to each device is stored. It is done by being executed. However, these access right control programs are stored in each device as long as the server 11 and the first and second client devices 13 and 15 can read and execute them corresponding to each device. It may be stored in a storage medium other than the area.

In FIG. 5, the second client device 1
The data request unit 152 of the first client device 1
3 requests the list of data managed by the first client device 13 from the data list in which the contents are described.
(Step S1). In step S1, the second
When the user of the client device 15 operates the input device 156, the request for the data list is transmitted to the data request unit 152. Then, the data request unit 152 requests the first client device 13 for the data list via the inter-client communication unit 151.

Next, the inter-client communication section 134 of the first client device 13 is
5, the data list is requested, and the request for the data list is transmitted to the data transmission unit 133 (step S2). next,
The data transmission unit 133 searches the data managed by the data storage device 14 by controlling the storage device control unit 135, and creates a data list managed by the data storage device 14 (step S3). Then, the data transmission unit 133 transmits the data list created in step S3 to the second client device 15 via the inter-client communication unit 134 (step S4).

Next, the inter-client communication section 151 of the second client device 15 receives the data list transmitted from the first client device 13 in step S4, and the display device 155 of the second client device 15 is received. A list of data received by is displayed (step S
5). Next, the user of the second client device 15
Desired data is selected from the data list displayed on the display device 155, and the selection result is transmitted to the data request unit 152 by operating the input device 156 (step S).
6). Then, the data request unit 152 uses the file name to be provided for identifying the data selected in step S6 and the provider identifier (that is, the identifier of the second client device 15) for identifying itself as the inter-client communication unit. Data is requested from the first client device 13 by transmitting via 151 (step S7).

Next, the inter-client communication section 134 of the first client equipment 13 is connected to the second client equipment 1
The file name of the file to be provided and the identifier of the file providing destination that are requested by the server 5 are received, and the request is sent to the access permission inquiry unit 132 (step S8). Next, the access permission / inquiry unit 132 determines that the second client device 15
In order to determine whether or not to access the data requested by the request, as an access right inquiry to the request, the file name to be provided, the destination identifier, and the source identifier for identifying itself (that is, the first source identifier). The identifier of the client device 13) is used as the inter-server communication unit 1
It transmits to the server 11 via 31 (step S9).

Next, the inter-client communication unit 113 of the server 11 accesses the file name to be provided, the provider identifier, and the provider identifier transmitted from the first client device 13 as an access right inquiry. It is sent to the availability determination unit 111 (step S10). Next, the access permission / inhibition determination unit 111 controls the database control unit 112 in response to the access right inquiry, refers to the access right management list stored in the access right management database 12, and refers to the requested data. Access right is determined (step S11). The detailed operation of the access right determination processing in step S11 will be described later. Then, the accessibility determination unit 11
1 shows the result of determining the access right to the data requested in step S11 as the inter-client communication unit 113.
To the first client device 13 via (step S12). Further, in the registration data referred to from the access right management list in step S11, if a restriction of "duplication condition" described later is described, information indicating the duplication condition in the step S12 (hereinafter referred to as duplication condition information). Is also transmitted to the first client device 13 at the same time.

Next, the inter-server communication section 131 of the first client device 13 receives the access right determination result transmitted from the server 11 and sends it to the data transmission section 133 (step S13). Next, the data transmission unit 133 determines whether or not the data requested by the second client device 15 in step S8 can be accessed from the access right determination result (step S14). The data transmission unit 133
When the access right determination result indicates that the data is accessible, the data requested by the second client device 15 in step S8 is searched from the data storage device 14 by controlling the storage device control unit 135, and the data is retrieved. Is transmitted to the second client device 15 via the inter-client communication unit 134 (step S15). If the copy condition information is also sent at the same time in step S12, the requested data is sent to the second client device 15 together with the copy condition information. On the other hand, if the access right determination result indicates that access is not possible, data transmission to the second client device 15 is rejected.

Next, the inter-client communication section 151 of the second client device 15 receives the data transmitted in step S15 and sends it to the data receiving section 153 (step S16). Then, the data receiving unit 153 controls the storage device control unit 154 to store the data received in step S16 in the data storage device 16 or display the data on the display device 155. Further, when the data received in step S16 is received together with the copy condition information, the data is limited to the copy condition information for the subsequent copy. It should be noted that the limitation of this duplication will be described later.

Next, the data structure of the access right management list stored in the access right management database 12 will be described with reference to FIG. Note that FIG. 6 is an example of the access right management list stored in the access right management database 12. In FIG. 6, data registered in the access right management list stored in the access right management database 12 is “number”, “provider identifier”, “file name”, “provider identifier”, “time condition”. , “Number of times condition”, and “replication condition”.

The "number" in the access right management list is
In the access right management database 12, it is a natural number that is used to manage each registered data and that avoids duplication.

The "provider identifier" of the access right management list is an identifier unique to each client device for specifying the terminal (that is, the client device of the provider) from which the data is provided.

The "file name" of the access right management list is the file name of the data to be accessed. The file name may include a content ID that is identification information unique to the content.

The "provider identifier" of the access right management list is an identifier unique to each client device for specifying the terminal (that is, the client device of the provider) to which the data is provided. This "provider identifier"
Describes not only a specific client device but also “arbitrary” when access is permitted to any client device. If access is not granted to all client devices, it is described as "impossible" or not described.

“Time condition” of the access right management list
Is a time limit for performing access permission that specifies the date when data is permitted to be provided and the period when data is permitted to be provided. If there is no time limit for accessing the data, it is described as "arbitrary".

“Count condition” of the access right management list
Is a condition relating to the number of times data is permitted to be provided from the terminal which is the source of the data. This "count condition"
In the data for which the above number of times is set, when the server 11 grants the access right to the data, the “number of times condition” is given.
Is updated, and when the “number of times condition” is updated to “0 times”, subsequent access is not permitted. In addition, when the condition regarding the number of times is not provided in the data of the access right management list, it is described as “arbitrary”.

“Replication condition” of the access right management list
Is a condition indicating whether or not further copying of the provided data is permitted in the terminal of the providing destination. This “replication condition” is described as “impossible” if the registration data is not permitted to be replicated after being provided, and is described as “arbitrary” if there is no particular condition regarding the replication. When the number is limited, the number of generations (for example, “only one generation is allowed” described in “number” “4”) is described.

Registration data is described in the access right management list for each of the above-mentioned items. For example, "number" is "1"
The registration data is the registration data for managing the access right with respect to the audio file "file name""birthvoice.wav" stored in the terminal with the "provider identifier" being "1111". Only the terminal having the “provider identifier” of “2222” can access this audio file. Further, there is no restriction on the date and time of access to the terminal “2222”. However, it is prohibited to further copy the provided file "Birth voice.wav" at the terminal "2222" of the provision destination.

Further, for example, the registration data with the “number” of “4” is the access right for the image file “file name” “child.jpg” stored in the terminal with the “provider identifier” of “1111”. This is registration data for managing. Only the terminals having the “provider identifiers” of “2222” and “3333” can access this image file. Then, the date and time when the terminals “2222” and “3333” are accessible are “20
Limited to "01/07/31", that is, 2001 July
It is accessible until the 31st of the month, and is inaccessible after that. The above "2222" and "333"
There is no restriction on the number of times the “3” terminal accesses. Further, the terminals “2222” and “3333” of the provision destination are permitted to copy the provided file “children.jpg” for only one generation.

Further, the registration data whose "number" is "9" is registration data for managing a special access right. In this registration data, the “provider identifier” is “444
The terminal "4" is data for access right management to the terminal whose "provider identifier" is "1111", but the "file name" is "arbitrary". That is, it means that the terminal of "1111" can access all the files stored in the terminal of "4444". In this type of usage, the "number" is "11".
This is used when the owners of the terminals “11” and “4444” are the same person and mutual file access is permitted unconditionally.

The registration data described in the access right management list stored in the access right management database 12 described above can be described under the following conditions. Condition 1: Among the data managed by all client devices whose access rights are managed by the server 11, the data that can be provided to other client devices or provided with some condition are described in the access right management list. To do.
(That is, data that is not described in the access right management list cannot be accessed.) Condition 2: Among the data managed by all the client devices that manage the access right by the server 11, it cannot be provided to other client devices or Describe the data that can be provided with some conditions in the access right management list. (In other words, data that is not described in the access right management list can be accessed)

Next, step S11 (see FIG. 5).
The detailed operation of the access right determination processing performed by the access permission determination unit 111 will be described. 7. Note that FIG. 7 is a subroutine of the above step S11 showing an example of a detailed operation of the access right determination processing performed by the access permission determination unit 111. Further, the access right management database 12 described above
It is assumed that the registration data described in the access right management list stored in (1) is described based on the above condition 1 (that is, data not described in the access right management list cannot be accessed).

In FIG. 7, the access permission / prohibition determination unit 111
Is an access in which a provider identifier for identifying a client device of a provider, a destination identifier for identifying a client device of a destination, and a file name of a target file for identifying data to be provided are described. A right inquiry is acquired (step S111). Next, the accessibility determination unit 111 sets 1 to initialize the temporary variable n used in the subroutine (step S112).

Next, the access permission / inhibition decision section 111 determines that the provider identifier acquired in step S111 and the "number" described in the access right management list stored in the access right management database 12 are "n". It is determined whether or not the “provider identifier” of the registration data “” matches (step S113). Then, the access permission / inhibition determination unit 111 advances the processing to the next step S114 when the agreement is obtained in step S113. On the other hand, if the access permission determination unit 111 does not match in step S113, the process proceeds to the next step S119.

In step S114, the access permission / inhibition determination section 111 determines the file name to be provided acquired in step S111 and the "file name" of the registration data whose "number" is "n" described in the access right management list. It is determined whether or not As described above, the "file name" of the access right management list may be set to "arbitrary". In this case, the accessibility determination unit 111 determines that the provision target file name acquired in step S111 matches the “file name” in the access right management list. Then, the access permission / inhibition determination unit 111 proceeds the processing to the next step S115 when the agreement is obtained in step S114. On the other hand, the access permission / inhibition determination unit 111 determines that the above step S11 is performed.
If they do not match in step 4, the process proceeds to the next step S119.

In step S115, the access permission / inhibition determining section 111 determines the provision destination identifier acquired in step S111 and the "providing destination identifier" of the registration data whose "number" is "n" described in the access right management list. It is determined whether or not Note that, as described above, the “provider identifier” of the access right management list may be set to “arbitrary”. In this case, the access permission / inhibition determination unit 111 determines that the provision destination identifier acquired in step S111 matches the “providing destination identifier” in the access right management list. Then, the access permission / inhibition determination unit 111 advances the processing to the next step S116 when the agreement is obtained at the step S115. On the other hand, if the access permission determination unit 111 does not match in step S115, the process proceeds to step S119.

In step S116, the access permission / inhibition decision section 111 compares the current time with the “time condition” of the registration data whose “number” is “n” described in the access right management list to determine whether or not access is permitted. judge. The above-described comparison performed by the access permission / inhibition determination unit 111 is determined to be accessible when the “time condition” is described as “arbitrary”, and is currently determined when the time constraint is described in the “time condition”. It is determined whether the time satisfies the constraint. Then, when the access permission / inhibition determination unit 111 determines in step S116 that the access is permitted, the process proceeds to the next step S117. On the other hand, the accessibility determination unit 1
When determining that the access is impossible in step S116, the process proceeds to the next step S119.

In step S117, the access permission / inhibition decision section 111 refers to the "number of times condition" of the registration data whose "number" is "n" described in the access right management list to determine the access permission / inhibition. In the above determination made by the access permission / inhibition determination unit 111, when "any number" or "number of times of one or more" is described in the "number of times condition", it is determined that the access is permitted and "0 times" is set in the "number of times condition". Is described, it is determined that access is impossible. In addition, the access permission / inhibition determination unit 111 determines that the “number of times is one or more” is described in the “count condition”, determines that the access is permitted, and then decreases the number of times described in the “count condition” by 1 to set the access right. Update the management list. Then, when the access permission / inhibition determination unit 111 determines in step S117 that the access is permitted, the process proceeds to the next step S118. on the other hand,
If the access permission / inhibition determination unit 111 determines in step S117 that access is not possible, the process proceeds to step S119.

In the step S117, as a method of updating the “number of times condition” of the access right management list, a method has been explained in which the number of times is always reduced by one when accessing from any client device when it is determined that access is possible. . However, when a plurality of “provider identifiers” are set, those client devices do not share one “count condition”, but each client device to which the data is provided has a “count condition”. It doesn't matter if you give it.

In step S118, the access permission / inhibition determination unit 111 determines that the access right inquiry obtained in step S111 is accessible and ends the subroutine. It should be noted that the process of step S118 can be performed only when the access permission / inhibition determination unit 111 matches the content of the access right inquiry acquired in step S111 in steps S113 to S117 and satisfies all the access conditions. Therefore, the access permission / inhibition determination unit 111 determines access permission only to the client devices that match the registration data description of the access right management list and satisfy the respective conditions.

On the other hand, as described above, if the access right inquiry obtained in step S111 does not satisfy any of the results determined in steps S113 to S117, the access permission / inhibition determination section 111 determines in step S1.
The process proceeds to 19. In step S119, the accessibility determination unit 111 increments the temporary variable n used in the subroutine by 1 to n + 1, and advances the process to step S120.

In step S120, the accessibility determination unit 111 determines whether or not the current temporary variable n is larger than the data registration number N of the access right management list. Then, the accessibility determination unit 111 determines that n>
In the case of N, it is determined that all the registration data of the access right management list have been searched, and the process proceeds to the next step S121. On the other hand, if n ≦ N, the accessibility determination unit 111 determines that there is registration data that has not been searched for in the access right management list, returns to step S113, and sets the new “number” set in step S119. , And perform a similar search.

In step S121, the access permission / inhibition determination section 111 determines that the access right inquiry obtained in step S111 is not accessible, and ends the subroutine. The process of step S121 is performed when the contents of the access right inquiry obtained by the access permission determination unit 111 in step S111 in steps S113 to S117 do not match, or when any of the access conditions is not satisfied. To be done. That is, the access permission / inhibition determination unit 111 determines that the content of the access right inquiry does not match any of the registered data descriptions in the access right management list, or does not satisfy any of the conditions, It is determined that access is impossible.

In the access right determination process performed by the access permission / inhibition determination section 111 shown in FIG. 7 described above, the registration data described in the access right management list stored in the access right management database 12 has the above condition 1 However, the registration data may be described based on the condition 2 (that is, data not described in the access right management list is accessible). In that case, the operation procedure of the access right determination processing performed by the access permission / inhibition determination unit 111 shown in FIG. 7 described above can be handled by changing only the steps described below. That is, with reference to FIG. 8, the access permission / inhibition determination unit 111 determines that the above steps S115 to S1.
When it is determined to be “no” in 17, the above step S121
In step S111, the access right inquiry obtained in step S111 is determined to be inaccessible, and the subroutine ends. In addition, the accessibility determination unit 1
If n> N in step S120, the process proceeds to step S118, the process 11 determines that the access right inquiry acquired in step S111 is accessible, and ends the subroutine. In this way, the access permission / inhibition determination unit 111 can appropriately determine the access permission / inhibition for the access right management list described by a plurality of description conditions by using the operation procedure according to the description conditions. .

Although the method of authenticating the first and second client devices 13 and 15 is not described in the description of the first embodiment, the server 11 and the first and second client devices 13 and 15 are described. It may be possible to confirm that the communication from the client device is correct by authenticating with the client. That is, at the time of communication from the second client device 15 to the first client device 13, the second client certificate for certifying that the second client device 15 is transmitted, When communicating from the client device 13 to the server 11,
By transmitting the second client certificate and the first client certificate proving that it is the first client device 13 to the server 11, the server 1
1 can authenticate these certificates and confirm that the communication is from the correct client device. As the certificate used at this time, for example, X. which is the standard specification of the electronic key certificate and the certificate revocation list. Fifty
9 or the like can be used.

When the server 11 sends the access condition determination result and the copy condition information to the first client device 13, the server 11 performs a predetermined encryption on the copy condition information. . For example, the server 11
By signing and transmitting the above-mentioned duplication condition information with the private key owned by, the legitimacy is assured to the second client device 15 to which the data to which this duplication condition is applied is provided. Data to which this duplication condition is applied is DRM (Digital Rights Mana).
encryption). For example, in the first client device 13 that is the data provider, when the replication condition information is transmitted from the server 11 together with the determination result of the access right, the second client is applied to data to which the replication condition information is applied. It is encrypted with the public key disclosed by the device 15 and transmitted to the second client device 15 together with the above-mentioned copy condition information. Then, in the second client device 15, the private key is stored in the tamper resistant area and kept secret to the user of the device. As a result, even if the above-mentioned data is illegally copied to other than the second client device 15, the data cannot be decrypted, and the copying is substantially limited. When copying is performed according to the above-mentioned duplication conditions, the encrypted data must be decrypted once with the secret key of the second client device 15 and then encrypted again with the public key disclosed by the duplication destination device. It is possible to restrict duplication.
Although the data is directly encrypted with the public key here, the data is encrypted with the common key encryption key, and the encryption key used here is used with the public key disclosed by the second client device 15. The first client device 13 may encrypt and send the encryption key together with the encrypted data. If the signature of the above-mentioned copy condition information has been tampered with (that is, not the information from the server 11),
It is not possible to copy the data to which the copy condition information is applied.

Regarding the confidentiality and tampering resistance regarding the path of the communication performed between the server 11 and the first and second client devices 13 and 15, a method is particularly described in the first embodiment. However, encrypted communication using an encryption method that combines a secret key method and a session key may be performed. As such encrypted communication, SSL (Secure Socket Layer) is used.
r) or the like can be used.

In the first embodiment, the first client device 13 creates the data stored in the data storage device 14 managed by itself as the data list in the step S3. Only the data accessible by the client device 15 may be created as the data list. This is because the first client device 13 receives the data list request from the second client device 15 in step S2, and returns the data accessible by the second client device 15 to the server 11. Inquiries about access rights. As a result of the access right inquiry, the above-mentioned data list is created based on the data that is determined to be provided to the second client device 15, and only accessible data is created as the above-mentioned data list. You can Even after the second client device 15 makes a request for data using the data list in which only the accessible data is described, the first client device 13 again gives the access right to the server 11. You may make an inquiry.

As described above, according to the access right control system of the first embodiment, the access right at the time of performing the peer-to-peer data exchange is checked by inquiring the access right from the client device which is the data provider. Since the control is performed on the side of the server having a high processing capability, it becomes possible to appropriately process even a complicated access right control. While realizing such complicated access right control, the data itself to be exchanged can be exchanged without directly putting the load on the server on the network band by directly transmitting / receiving between the client devices. is there. Even if the client device is composed of a consumer device with a limited processing capacity, since the complicated access right control is processed by the server, it is possible to perform peer-to-peer data exchange by a consumer device with a restricted processing capability. On the other hand, the above-mentioned complicated access right control can be easily added.

(Second Embodiment) With reference to FIG. 9, an overall configuration of an access right control system according to a second embodiment of the present invention will be described. In the above-described first embodiment, the client device that is the data provider (that is, the first client device 13 that is the access destination) inquires the server 11 of the access right.
The second embodiment is an access right control system in which a client device (that is, an access source client device) that is a data providing destination makes an inquiry about an access right to a server.

In FIG. 9, the access right control system includes a server 21, an access right management database 22,
First client device 23, data storage device 24, second client device 25, and data storage device 26
Is equipped with. First and second client device 23
Reference numerals 25 and 25 are devices equipped with CPUs owned by end users, which form peer-to-peer computing that directly communicates with each other and form a peer-to-peer type file exchange system. Also, the server 21
Is communicatively connected to a client device arranged in the peer-to-peer type file exchange system, and at least the second client device 25 is configured to be accessible to the server 21. The data storage devices 24 and 26 are storage devices that store files and the like managed by the first and second client devices 23 and 25, respectively. The access right management database 22 is a storage device that stores an access right management list, which will be described later, managed by the server 21.

In the description of this embodiment, in order to simplify the description, the second client device 25 provides the desired file stored in the data storage device 24 managed by the first client device 23. Assuming a case of accessing for receiving, the first client device 23 is an access destination (hereinafter, referred to as a provider) client device, and the second client device 25 is an access source (hereinafter,
The client device will be described as a "providing party"). Further, in the access right control system, 2
It is possible to deploy more than one client device, but here only the client device related to the access of the file will be described.

Next, the internal structure of the server 21 will be described with reference to FIG. Note that FIG. 10 is a functional block diagram showing the internal configuration of the server 21. In FIG. 10, the server 21 includes an accessibility determination unit 211, a database control unit 212, and an inter-client communication unit 213. The client-to-client communication unit 213 uses TCP / I
The second client device 2 using a protocol such as P
5 and the server 21 are communicated. The database control unit 212 controls the data stored in the access right management database 22. For example, when the access control unit 211 requests the data stored in the access right management database 22, the database control unit 212 searches the data in the access right management database 22 according to the request, or The data of is updated. Also, the database control unit 212
Adds or deletes data in the access right management database 22 in response to a request from a client device instructed via the inter-client communication unit 213.
When the second client device 25, which will be described later, requests an access right determination via the inter-client communication unit 213, the access permission / inhibition determination unit 211 refers to the access right management list of the access right management database 22 from the content thereof. The access right determination result is returned to the inter-client communication unit 213. If it is determined that the access right management list needs to be updated, the database control unit 212 is instructed to update the access right management list.

Next, the internal configuration of the first client device 23 will be described with reference to FIG. Note that FIG.
FIG. 1 is a functional block diagram showing an internal configuration of the first client device 23. In FIG. 11, the first client device 23 includes an inter-client communication unit 231, a data transmission unit 232, and a storage device control unit 233. The inter-client communication unit 231 uses a protocol such as TCP / IP and performs communication between the first client device 23 and the second client device 25. When the data transmission unit 232 is requested by the second client device 25 to list the data stored in the data storage device 24 via the inter-client communication unit 231, the data transmission unit 232 sends the data storage device via the storage device control unit 233. A list of data stored in 24 is generated, and the data list is provided to the second client device 25. In addition, the data transmission unit 232
When the result of determining that the server 21 is accessible from the second client device 25 is transmitted, the data storage device 24 is transmitted via the storage device controller 233.
The requested data is obtained, and this data is transmitted to the second client device 25 by controlling the inter-client communication unit 231. In addition, the first client device 23
Has a unique identifier, and this identifier is stored in an identifier storage unit (not shown). The identifier may be information unique to the CPU provided in the first client device 23 or an IP address.

Next, the internal configuration of the second client device 25 will be described with reference to FIG. Note that FIG.
2 is a functional block diagram showing an internal configuration of the second client device 25. In FIG. 12, the second client device 25 includes an inter-server communication unit 251, an access permission inquiry unit 252, a data request unit 253, an inter-client communication unit 254, a storage device control unit 255, a data receiving unit 256, and a display device 257. And input device 258
Is equipped with. The server-to-server communication unit 251 uses TCP / IP.
Second client device 25 using a protocol such as
Communication with the server 21. The inter-client communication unit 254 uses a protocol such as TCP / IP to perform communication between the first client device 23 and the second client device 25. The display device 257 prompts the user of the second client device 25 to select from the data list by displaying the data list received from the first client device 23 via the inter-client communication unit 254, for example. The input device 258 selects desired data from the data list by a user operation. The data request unit 253 instructs the access permission / inquiry unit 252 to inquire about the determination of the access right to the data selected by the user, and acquires the selected data based on the determination result. Communication for requesting data to the device 23 is performed via the inter-client communication unit 254. When accepting a data request from the data requesting unit 253, the access permission / inquiry unit 252 makes an inquiry to the server 21 via the inter-server communication unit 251 in order to determine the accessibility of the data. When the above access is permitted, the data receiving unit 256 receives the data from the first client device 23 via the inter-client communication unit 254, and the storage device control unit 255 controls the data storage device 26 to cause the data. Are stored in the data storage device 26.
Also, the second client device 25 has a unique identifier, and this identifier is stored in an identifier storage unit (not shown).
Stored in. The identifier may be information unique to the CPU provided in the second client device 25 or an IP address.

In this embodiment, the first and second
It has been described that the client devices 23 and 25 have different internal configurations. Such a difference is
This is because it is assumed that the first client device 23 is the data provider and the second client device 25 is the data provider as described above. Therefore, when it is convenient for the first and second client devices 23 and 25 to be both the source and the destination, it is sufficient to provide each client device with the function of both client devices. .

Next, the overall processing of the access right control system according to the second embodiment will be described with reference to FIG. Note that FIG. 13 shows the server 21, the first and second client devices 2 that constitute the access right control system.
3 is a flowchart showing the operations performed by 3 and 25. Regarding the overall processing of the access right control system described here, it is assumed that the first client device 23 is the data provider and the second client device 25 is the data provider, and the second client device 25 Data storage device 2 managed by the first client device 26
A case where desired data stored in No. 4 is acquired will be described. The processing operation of this access right control system is performed by the server 21, the first and second client devices 2
In 3 and 25, the access right control program corresponding to each device is stored in the storage area provided in each device and executed. However,
These access right control programs are other than the storage area provided in each device as long as the server 21 and the first and second client devices 23 and 25 can read and execute them corresponding to each device. It may be stored in another storage medium.

In FIG. 13, the data request unit 253 of the second client device 25 requests a list of data managed by the first client device 23, so that the data list in which the contents are described is the first data list. Client device 2
3 is requested (step S21). In step S21, the user of the second client device 25 makes the input device 2
By operating 58, the data list request is transmitted to the data request unit 253. Then, the data request unit 2
53 via the inter-client communication unit 254,
The data list is requested of the first client device 23.

Next, the inter-client communication section 231 of the first client device 23 uses the second client device 2
5, the data list is requested, and the request for the data list is transmitted to the data transmission unit 232 (step S22). Next, the data transmission unit 232 searches the data managed by the data storage device 24 by controlling the storage device control unit 233, and creates a data list managed by the data storage device 24 (step S23). ). And
The data transmission unit 232 transmits the data list created in step S23 to the second client device 25 via the inter-client communication unit 231 (step S2).
4).

Next, the inter-client communication unit 254 of the second client device 25 makes the first communication in step S24.
The data list transmitted from the client device 23 is received, and the received data list is displayed by the display device 257 of the second client device 25 (step S2).
5). Next, the user of the second client device 25
Desired data is selected from the data list displayed on the display device 257, and the selection result is transmitted to the data request unit 253 by operating the input device 258 (step S2).
6). Then, the data request unit 253, the step S26.
The file name to be provided for identifying the data selected in step 3 and the provider identifier (that is, the identifier of the first client device 23) for determining the source terminal are sent to the access permission / inquiry section 252. Next, the access permission / inquiry unit 252 determines, in order to determine whether or not the data requested by the data requesting unit 253 is accessible, as an access right inquiry to the request, the file name to be provided, the source identifier, and the self The provider identifier (that is, the identifier of the second client device 25) for determining is transmitted to the server 21 via the inter-server communication unit 251 (step S27).

Next, the inter-client communication section 213 of the server 21 accesses the file name to be provided, the destination identifier, and the source identifier transmitted from the second client device 25 as an access right inquiry. It is sent to the availability determination unit 211 (step S28). Next, the access permission / inhibition determination unit 211 controls the database control unit 212 in response to the access right inquiry, refers to the access right management list stored in the access right management database 22, and refers to the requested data. Access right is determined (step S29). The access right determination processing in step S29 will be described later. Then, the access permission / inhibition determination unit 211 performs predetermined encryption on the result of determination of the access right to the data requested in step S29, and then executes the second client device 25 via the inter-client communication unit 213.
(Step S30). In addition, the above step S
In the registration data referred to from the access right management list in 29, when the restriction of “replication condition” is described, the replication condition information is also transmitted to the second client device 25 at the same time in step S30.

The encryption of the result of the access right judgment performed in step S30 is to ensure the validity of the result of the access right judgment by the server 21. For example, by encrypting the determination result of the access right with a public key disclosed by the first client device 23, or by adding data signed with a private key owned by the server 21 and transmitting the data, the validity is obtained. Is guaranteed. That is, by this encryption, it is possible to prevent falsification during communication, and in the validity evaluation of the first client device 23 described later, it is possible to reliably determine that the result is the result determined by the server 21. Is.

Next, the inter-server communication section 251 of the second client device 25 receives the access right judgment result transmitted from the server 21 and sends it to the data request section 253 (step S31). Next, the data request unit 253 determines whether or not the data selected in step S26 can be accessed based on the access right determination result (step S32). When the access right determination result indicates that the access is possible, the data request unit 253 transmits the provision target file name together with the access right determination result transmitted from the server 21 via the inter-client communication unit 254. , Request data from the first client device 23 (step S33). If the copy condition information is also transmitted at the same time in step S30,
A request is made to the first client device 23 together with the copy condition information. On the other hand, when the access right determination result indicates that access is not possible, the second client device 25 cancels the data request to the first client device 23.

Next, the inter-client communication section 231 of the first client device 23 operates the second client device 2
The file name of the file to be provided and the access right determination result requested by No. 5 are received and sent to the data transmission unit 232 (step S34). Then, the data transmission unit 232
The validity of the access right determination result is determined based on whether or not the result is determined by the server 21 (step S
35). In this step S35, the data transmission unit 232
Can confirm the validity by solving the access right determination result encrypted by the server 21 in step S30. Then, the data transmission unit 23
When the access right determination result is valid, the second control unit 233 searches the data storage device 24 for the data requested by the second client device 25, and retrieves the data from the client. It is transmitted to the second client device 25 via the intercommunication unit 231 (step S36). If the copy condition information is also sent at the same time in step S33, the requested data is sent to the second client device 25 together with the copy condition information. On the other hand, if the access right determination result is not valid, data transmission to the second client device 25 is rejected.

Next, the inter-client communication section 254 of the second client device 25 receives the data transmitted in the above step S36 and sends it to the data receiving section 256 (step S37). Then, the data receiving unit 256 controls the storage device control unit 255 to store the data received in step S37 in the data storage device 26 or display the data on the display device 257. When the data received in step S37 is received together with the duplication condition information, the data is limited to the duplication condition information for subsequent duplication. It should be noted that the limitation of this duplication will be described later.

The data structure of the access right management list stored in the access right management database 22 is the same as the data structure of the first embodiment described with reference to FIG. The detailed operation of the access right determination processing performed by the access permission / inhibition determination unit 211 in step S29 (see FIG. 13) is also the same as that of the subroutine of the first embodiment described with reference to FIG. That is, even in the second embodiment, the access permission / inhibition determination unit 211 appropriately uses the operation procedure according to the description condition for the access right management list described in the plurality of description conditions. Can be determined. Therefore, in the second embodiment, detailed description of the data structure of the access right management list and the detailed operation of the access right determination processing performed by the access permission / inhibition determination unit 211 will be omitted.

In the second embodiment, the first client device 23 creates the data stored in the data storage device 24 managed by itself as the data list in the above step S23. The client device 25 may obtain the data list from the server 21 by inquiring the server 21 about only the data accessible from the first client device 23. This is because the second client device 25 sends a data list request to the server 21 in step S21 to make an access right inquiry so that the second client device 25 sends back accessible data. Then, in the server 21, the data accessible by the second client device 25 is searched from the access right management list to create the data list, and only the accessible data is created as the data list. It can be sent to the client device 25.

Further, in the explanation of the second embodiment, although the method concerning the authentication of the second client device 25 is not described, between the server 21 and the first and second client devices 23 and 25, You may confirm that the communication is from the correct client device by authentication. That is, at the time of communication from the second client device 25 to the first client device 23 or the server 21, a second client certificate for certifying that it is the second client device 25 should be transmitted. The server 21 and the first client device 23
By authenticating this certificate, it is possible to confirm that the communication is from the correct client device. As the certificate used at this time, for example, X. which is the standard specification of the electronic key certificate and the certificate revocation list. 509 or the like can be used.

When the server 21 sends the access condition determination result and the copy condition information to the second client device 25, the server 21 performs a predetermined encryption on the copy condition information. . For example, the server 21
By signing and transmitting the above-mentioned duplication condition information with the private key possessed by, the legitimacy is assured to the second client device 25 to which the data to which this duplication condition is applied is provided. Data to which this duplication condition is applied is DRM (Digital Rights Mana).
encryption). For example, in the first client device 23 that is the data provider, when the copy condition information is transmitted from the server 21 together with the access right determination result, the second client device 23 applies to the data to which the copy condition information is applied. It is encrypted with the public key disclosed by the device 25 and transmitted to the second client device 25 together with the above-mentioned copy condition information. Then, in the second client device 25, the private key is stored in the tamper resistant area and kept secret to the user of the device. As a result, even if the above-mentioned data is illegally copied to a part other than the second client device 25, the data cannot be decrypted and the copy is substantially limited. When copying is performed according to the above-mentioned duplication conditions, the encrypted data must be decrypted once with the secret key of the second client device 25, and encrypted again with the public key disclosed by the duplication destination device. It is possible to restrict duplication.
Although it is assumed here that the data is directly encrypted with the public key, the data is encrypted with the common key encryption key, and the encryption key used here is used with the public key that the second client device 25 publishes. The first client device 23 may encrypt and send the encryption key together with the encrypted data. In addition, when the signature of the copy condition information is falsified (that is, not the information from the server 21),
It is not possible to copy the data to which the copy condition information is applied.

Regarding the confidentiality and tampering resistance regarding the path of communication performed between the server 21 and the first and second client devices 23 and 25, the second embodiment particularly describes the method. However, encrypted communication using an encryption method that combines a secret key method and a session key may be performed. As such encrypted communication, SSL (Secure Socket Layer) is used.
r) or the like can be used.

As described above, according to the access right control system according to the second embodiment, by inquiring the access right from the client device to which the data is provided, the access right at the time of performing the peer-to-peer data exchange can be confirmed. Since the control is performed on the side of the server having a high processing capability, it becomes possible to appropriately process even a complicated access right control. While realizing such complicated access right control, the data itself to be exchanged can be exchanged without directly putting the load on the server on the network band by directly transmitting / receiving between the client devices. is there. Even if the client device is composed of a consumer device with a limited processing capacity, since the complicated access right control is processed by the server, it is possible to perform peer-to-peer data exchange by a consumer device with a restricted processing capability. On the other hand, the above-mentioned complicated access right control can be easily added.

In the access right control system according to the first and second embodiments described above, the client device directly connected to the server requests the server to determine the access right, and the result is sent to the other client. Although it is configured to be transmitted to the device, the client device requesting the determination of the access right and the server do not have to be directly connected. If the server is communicatively connected to the client device arranged in the peer-to-peer type file exchange system, the client device as another proxy (the third client device and the third client device) capable of directly communicating with the server. The present invention can be realized by the communication between the client device requesting the determination of the access right and the server via the communication. For example, in the above-described first embodiment, when the first client device 13 cannot directly communicate with the server 11,
A similar access right control system can be configured by the first client device 13 communicating with the server 11 via the third client device. Further, in the above-described second embodiment, when the second client device 25 cannot directly communicate with the server 21, the second client device 25 communicates with the server 21 via the third client device. By
A similar access right control system can be constructed. When configuring the access right control system via the third client device as described above, the third client certificate for certifying that the client device is the third client device is used, It goes without saying that the server can confirm that the communication is from the correct client device by authenticating each other.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an overall configuration of an access right control system according to a first embodiment of the present invention.

FIG. 2 is a functional block diagram showing an internal configuration of a server 11 shown in FIG.

3 is a functional block diagram showing an internal configuration of a first client device 13 shown in FIG. 1. FIG.

4 is a functional block diagram showing an internal configuration of a second client device 15 shown in FIG.

5 is a flowchart showing an overall operation performed by a server 11 and first and second client devices 13 and 15 shown in FIG. 1. FIG.

6 is a diagram illustrating a data structure of an access right management list stored in an access right management database 12 shown in FIG.

7 is a subroutine showing an example of a detailed operation of an access right determination process performed by an access permission / inhibition determination section 111 in step S11 shown in FIG.

8 is a subroutine showing another example of detailed operation of the access right determination processing performed by the access permission / inhibition determination section 111 in step S11 shown in FIG.

FIG. 9 is a diagram illustrating an overall configuration of an access right control system according to a second exemplary embodiment of the present invention.

10 is a functional block diagram showing an internal configuration of the server 21 shown in FIG.

11 is a functional block diagram showing an internal configuration of a first client device 23 shown in FIG.

12 is a functional block diagram showing an internal configuration of a second client device 25 shown in FIG.

13 is a flowchart showing an overall operation performed by the server 21 and the first and second client devices 23 and 25 shown in FIG.

[Explanation of symbols]

11, 21 ... Server 12, 22 ... Access right management database 13, 23 ... First client device 14, 16, 24, 26 ... Data storage device 15, 25 ... Second client device 111, 211 ... Access permission determination unit 112, 212 ... Database control sections 113, 134, 151, 213, 231, 254 ... Inter-client communication section 131, 251, ... Inter-server communication section 132, 252 ... Access permission inquiry section 133, 132 ... Data transmission section 135, 154, 233, 255 ... Storage device control unit 152, 253 ... Data request unit 153, 256 ... Data receiving unit 155, 257 ... Display device 156, 258 ... Input device

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masahiro Oho             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 5B017 AA07 BA06 BB06 CA16                 5B082 EA11                 5B085 AE04 AE23 BA07 BE01 BE04                       BG02 BG07

Claims (27)

[Claims] 1. An access right control system for determining, when a client device owned by an end user is directly requested by another device to transmit data, an access right indicating whether or not the device can be accessed. A communication device that is communicatively connected to the client device and that manages an access right management list in which access rights of the client device are described in advance. The client device includes an access permission determination unit that determines the access right and returns a determination result by referring to the access right to the request when another device directly requests the data transmission. An access permission inquiry unit that inquires the access permission determination unit, Access right management including a data transmission unit that directly transmits the requested data to another device when the result of the inquiry by the inquiry unit indicates that the judgment result returned from the accessibility determination unit is accessible. system. 2. The access right management list managed by the server describes the access right indicating an accessible device for each data managed by each client device, and the access permission / inhibition inquiring unit is configured to access the data. For each data requested to be transmitted, the access permission / inhibition determination unit is inquired, and the access permission / inhibition determination unit determines the access right and returns the determination result in response to the inquiry for each data by the access permission / inhibition inquiry unit. The access right management system according to claim 1. 3. The access right management list managed by the server describes a time condition indicating an accessible time for each data, and the access permission / inhibition determination unit is inquired from the access permission / inhibition inquiry unit. The access right management system according to claim 2, wherein the access right is determined for each of the data by referring to the time condition according to the current time. 4. The access right management list managed by the server describes a frequency condition indicating the number of times access is possible for each data, and the access permission / inhibition determination unit is inquired from the access permission / inhibition inquiry unit. The access right is determined for each data by referring to the number condition according to the number of times
The access right management system according to claim 2. 5. The access right management list managed by the server further describes a copy condition indicating a restriction relating to the copy of the data provided for each of the data, and the access permission / inhibition determination unit is configured to access the access permission / denial. In response to an inquiry for each data by the inquiry unit, the access right is determined and the duplication condition is returned together with the determination result, and the data transmission unit, when the determination result returned from the access permission determination unit is accessible, The access right management system according to claim 2, wherein the requested data is added to the copy condition and directly transmitted to another device. 6. The access right management system according to claim 1, wherein the server is communicably connected to the client device via another proxy. 7. The access propriety inquiring unit is for certifying that it is the client device when the data transmission is requested from another device and the access right to the request is inquired to the access propriety judging unit. The first certificate and the second certificate for certifying the other device are added to the access permission determination unit, and the access permission determination unit determines the first and second certificates. The access right management system according to claim 1, wherein the access right is judged and the judgment result is returned after the inquiry from the access permission / inquiry unit is authenticated by using the authentication. 8. The certificate includes X. The access right control system according to claim 7, wherein 509 is used. 9. An access right for determining an access right indicating whether or not the second client device, when the second client device directly requests data transmission, to the first client device owned by the end user. A control system, comprising: a server that is communicably connected to at least the second client device, and that manages an access right management list in which access rights of at least the first and second client devices are described in advance. Includes an access permission / inhibition determination unit that determines the access right by referring to the access right management list in response to the inquiry about the access right, and returns a determination result, wherein the second client device is the first client device. When requesting direct data transmission to another client device, Access permission inquiry unit for inquiring about the access right to the access permission determination unit, and when the result of the inquiry made by the access permission determination unit is that the access is permitted, the first client device is accessed. On the other hand, including a data request unit for requesting the direct data transmission by adding the determination result, the first client device, if the determination result transmitted from the data request unit is accessible, The second client device further includes a data transmission unit that directly transmits the data requested by the data request unit to the second client device, the second client device further including the data transmission unit in response to a request from the data request unit. An access right management system including a data reception unit that directly receives data transmitted from the data transmission unit. Mu. 10. The access right management list managed by the server describes the access right indicating an accessible device for each data managed by each client device, and the access permission / inhibition inquiring unit sets the data An inquiry is made to the access permission / inhibition determination unit for each piece of data requested to be transmitted, and the access permission / inhibition determination unit determines the access right and returns a determination result in response to the inquiry for each data by the access permission / inhibition determination unit. The access right management system according to claim 9. 11. The access right management list managed by the server describes a time condition indicating an accessible time for each data, and the access permission / inhibition determination unit is inquired from the access permission / inquiry unit. The access right management system according to claim 10, wherein the access right is determined for each of the data by referring to the time condition according to the current time. 12. The access right management list managed by the server describes a number condition indicating the number of times access is possible for each data, and the access permission / inhibition determination unit is inquired from the access permission / inhibition inquiry unit. The access right is determined for each data by referring to the number condition according to the number of times
The access right management system according to claim 10. 13. The access right management list managed by the server further describes a copy condition indicating a restriction relating to the copy of the data provided for each of the data, and the access permission / inhibition determination unit is configured to perform the access permission / inhibition. In response to an inquiry for each data by the inquiry unit, the access right is determined and the duplication condition is returned together with the determination result, and the data request unit, when the determination result returned from the accessibility determination unit is accessible, When the direct transmission of data is requested to the first client device together with the determination result and the copy condition, and the data transmission unit is accessible when the determination result transmitted from the data request unit is accessible. Directly transmitting the duplication condition together with the data requested by the data requesting unit to the data receiving unit, Over data receiving unit, the receiving directly the data that is transmitted from the data transmission unit, the data is thereafter replicated by the replication conditions are restricted, the access right management system according to claim 10. 14. The access right management system according to claim 9, wherein the server is communicably connected to the second client device via another proxy. 15. The access permission / inhibition inquiring unit, in order to request the first client device to transmit data, queries the access permission / inhibition judging unit for the access right to the request, A query for certifying that the device is a client device is added to the access permission determination unit, and the access permission determination unit, after authenticating the inquiry from the access permission inquiry unit using the certificate, The access right management system according to claim 9, wherein the access right is judged and a judgment result is returned. 16. The access permission / inhibition determination unit further comprises:
When the determination result returned from the access permission / prohibition determination unit is accessible, the data request unit adds a signature to the determination result and replies with a signature for certifying that the determination is made by the server. Requesting the direct data transmission together with the determination result to which the signature is added and the certificate to the client device, and the data transmitting unit uses the signature of the determination result transmitted from the data requesting unit. 16. The access right management system according to claim 15, wherein when the determination result is accessible, the duplication condition is directly transmitted to the data receiving unit together with the data requested by the data requesting unit. . 17. The certificate includes X. The access right control system according to claim 15, wherein 509 is used. 18. A server which, when directly transmitting and receiving data managed by a client device among a plurality of client devices owned by an end user, determines an access right indicating whether or not the client device can access the data. An access right management unit that manages an access right management list in which device access rights are described in advance; and with respect to the access right inquiry transmitted from the client device, the access right management unit refers to the access right management list. A server including an access permission / inhibition determination unit that determines the access right and returns the determination result to the client device that made the inquiry. 19. When a direct data transmission is requested from another device, an access right indicating whether or not the device can be accessed,
A client device owned by an end user that causes a communicable server that manages an access right management list in which the access right is described in advance for each device, and when a direct data transmission is requested from another device. An access permission inquiry unit for inquiring the server about the access right to the request, and a result of the inquiry made by the access permission inquiry unit, and if the determination result returned from the server is accessable, according to a request from another device. A client device including a data transmission unit that directly performs the data transmission. 20. When a direct data transmission is requested to another device, a communicable server that manages an access right indicating permission / inhibition of the access right management list in which the access right is described in advance for each device. When the client device is owned by the end user, the access permission inquiry unit for inquiring the server about the access right to the request when directly requesting data transmission to the other device, and the access permission inquiry If the judgment result returned from the server is accessible as a result of the inquiry by the client, the client includes a data request unit that adds the judgment result to another device and requests the direct data transmission. machine. 21. A client device owned by an end user, which directly transmits data when requested by another device, wherein the request is for the direct data transmission from another device and is added to the request. If the determination result received by the reception unit is accessible, the data requested by another device is transmitted. A client device including a data transmission unit that transmits directly. 22. A signature for proving that it is a device that has determined the access right is added to the determination result, and the data transmission unit authenticates the signature of the determination result. 22. The client device according to claim 21, wherein the validity of the determination result is evaluated by, and the data requested by another device is directly transmitted when the determination result is valid and accessible. 23. When a client device owned by an end user is requested by another device to directly send data, an access right indicating whether or not the device can be accessed is connected to the client device so that the client device can communicate with the client device. In the server, the access right management step of managing an access right management list in which the access right of the client device is described in advance, the client device directly connecting to another device. Access permission inquiry step of inquiring the server about the access right to the request from the client device when the data transmission is requested, and the access right management step manages the inquiry by the access permission inquiry step. Access right management list By referring to the access right, the server determines the access right and returns a determination result to the client device. An access permission / inhibition determination step; if the determination result returned in the access permission / inhibition determination step is accessable, the requested data is returned. And a data transmission step of directly transmitting from the client device to another device. 24. When the second client device requests direct data transmission to the first client device owned by the end user, the second client device is provided with an access right indicating whether or not the data can be accessed. An access right control method for determining in a server communicatively connected to the server, wherein the server manages an access right management list in which access rights of at least the first and second client devices are described in advance. A rights management step, and when the second client device requests the first client device for direct data transmission, the second client device inquires the access right for the request from the second client device. Inquiry step and inquiry by the access permission inquiry step On the other hand, by referring to the access right management list managed in the access right management step, the access right is judged by the server and the judgment result is returned to the second client device. A data request step of requesting the direct data transmission by adding the determination result to the first client device when the determination result returned from the access permission / inhibition determination step is accessible, When the determination result transmitted by the data requesting step is accessible, the data transmitting step of directly transmitting the data requested by the data requesting step to the second client device; The data transmitted from the first client device is transferred to the second And a data receiving step of directly received by the client device,
Access right control method. 25. When a client device owned by an end user directly transmits / receives data managed by the client device, a server connected to the client device so that an access right indicating whether or not the client device is accessible can be communicated. An access right management step of managing an access right management list in which the access right of the client device is described in advance, which is a recording medium readable by the server, in which an access right control program for making a judgment is recorded. When directly transmitting and receiving data, the access right management list managed in the access right management step is displayed in response to an inquiry of the access right for the transmission and reception from the client device to the server. By referencing that access right Sectional determined result and an access permission determination step of replying to said client device, recording medium recording the access control program. 26. When a direct data transmission is requested from another device, an access right indicating whether or not the device can be accessed,
A recording medium readable by a client device owned by an end user, which stores an access right control program for controlling a communication-enabled server that manages an access right management list in which the access right is described in advance for each device, wherein the client When a device is requested by another device to directly transmit data, an access permission inquiry step for inquiring the server about the access right for the request, and an inquiry result by the access permission inquiry step are returned from the server. And a data transmission step of directly transmitting the requested data from the client device to another device when the determination result indicates that the recording medium records an access right control program. 27. A communicable server that manages an access right indicating permission of access when directly requesting data transmission to another device and an access right management list in which the access right is described in advance for each device. A recording medium readable by a client device owned by an end user, which stores an access right control program to be judged by the user, and when requesting direct data transmission to another device, the access right to the request is set to The access permission inquiry step of inquiring to the server, and when the determination result returned from the server is accessible as a result of the inquiry in the access permission inquiry step, the determination result is added to another device and the direct determination is performed. An access right control program including a data request step for requesting data transmission. Recording the recording medium.