WO2006059476A1

WO2006059476A1 - Data sharing system, copy content data storage control device, etc.

Info

Publication number: WO2006059476A1
Application number: PCT/JP2005/020811
Authority: WO
Inventors: Hiroaki Suzuki; Yoshihiko Hibino; Yuji Kiyohara; Kentaro Ushiyama; Koichi Iijima; Tomohiro Kudo; Osamu Tatebe; Yuetsu Kodama; Kazuyuki Shudo
Original assignee: Brother Kogyo Kabushiki Kaisha; Xing Inc.
Priority date: 2004-12-01
Filing date: 2005-11-14
Publication date: 2006-06-08
Also published as: JP4586203B2; JP2006155486A

Abstract

There are provided a data sharing system, a copy content data storage control device, and the like capable of holding an appropriate number of replicas of content data in each node device according to the popularity. The data sharing system includes a plurality of node devices connected to one another via a network. Copy content data obtained by copying content data which can be used in the plurality of node devices from one of the node devices is stored in at least one of the node devices. The copy content data storage control device controls storage of the copy content data. The copy content data storage control device includes: desired number-of-uses information acquisition means for acquiring the number-of-uses information indicating the desired number of uses of the content data; number-of-copies decision means for deciding the number of copies of the content data according tot he desired number-of-uses information acquired; node selection means for selecting the number of node devices corresponding to the number of copies decided; and content storage control means for transmitting storage request information indicating a request for storing the copy content data to the selected node device so that the copy content data is stored in such a manner that it can be used from the plurality node devices.

Description

Specification

Data sharing system, duplicate content data storage control device, etc.

The present invention is a data sharing system including node devices such as a plurality of terminal devices connected to each other via a network such as the Internet, and replicates content data that can be used by the plurality of node devices The present invention relates to a technical field such as a data sharing system in which the copied content data is stored in a node device with one or more powers.

Background art

[0002] As a conventional form of data sharing, a data sharing system based on a client 'server model is known, for example, NFS (Network File system).

[0003] However, in general, a server is required to have a high-performance CPU (Central Processing Unit) capable of withstanding a high load and ΐΖθ (Input / Output) specifications, and is expensive. Management was also complicated and required a skilled administrator. In addition, if the communication between the client and the server is interrupted for some reason, the service for the client is stopped.

[0004] On the other hand, unlike the above-mentioned client 'server model, on the other hand, an expensive server or a client required by a skilled administrator (hereinafter referred to as a "terminal device") can freely join and leave the network (eg, power supply) The peer-to-peer (P2P) model, which can be turned on and off), is attracting attention. Examples are Napster and Gnutella, which are famous for music distribution.

[0005] As a technique for data sharing in such a peer-to-peer model, for example, Patent Document 1 refers to the overall size and number of replicas registered in each device participating in a service group. A data sharing apparatus for creating and registering replicas so as to balance the entire network in the service group is disclosed.

Patent Document 1: Japanese Patent Laid-Open No. 2003-99337

Disclosure of the invention

Problems to be solved by the invention [0006] However, in such a conventional data sharing device, for example, the use frequency for each data for which a replica is created and the popularity are not taken into consideration. When there is a download request exceeding the amount, there is a problem that the load is concentrated on the device (terminal device) that holds the replica and cannot be handled.

[0007] The present invention has been made in view of the above problems and the like, and a data sharing system capable of holding an appropriate number of replicas of content data in each node device according to popularity, etc., and It is an object to provide a duplicate content data storage control device and the like. Means for solving the problem

In order to solve the above problems, according to one aspect of the present invention, there is provided a data sharing system including a plurality of node devices connected to each other via a network, the plurality of node devices. A duplicate content data storage control device for controlling the storage of the duplicate content data in the data sharing system in which the duplicate content data obtained by duplicating the content data usable in is stored in any one or more of the node devices, Desired use number information acquisition means for acquiring desired use number information indicating the desired use number of the content data, and a copy number determination for determining the copy number of the content data based on the acquired desired use number information Means, a node selection means for selecting a number of node devices corresponding to the determined number of replicas, and a preceding node device for the selected node device. Copy content data storage control means for transmitting storage request information indicating a storage request for the copy content data and storing the copy content data so as to be usable by the plurality of node devices.

Therefore, the number of copies corresponding to the desired number of content data is determined, the number of node devices corresponding to the number of copies is selected, and the copy content data (replica data) is selected for the selected node device. ) Can be stored, so that each node device can hold an appropriate number of replicas of content data according to popularity. Therefore, since the processing amount of the node device is balanced, load concentration (access concentration) on a specific node device can be avoided.

[0010] In addition, it further includes use request information receiving means for receiving use request information indicating the use request that has been transmitted, and the node device power that desires use of the content data, The desired number-of-use information acquiring means is characterized in that the desired-number-of-use information is acquired by counting the desired-for-use information.

[0011] Further, the use request information receiving unit receives the use request information only for a predetermined period.

[0012] Further, the copy number determination means determines the copy number of the content data based on a ratio between the desired use number and the number of node devices participating in the data sharing system. Features.

[0013] Accordingly, each node device can hold an optimal number of replicas of content data.

[0014] Further, it is characterized by further comprising usage restriction means for restricting the use of the content data and its duplicate content data for a predetermined period to a node device other than the node device that has transmitted the usage request information. To do.

[0015] Therefore, it is possible to increase the value (dominance) of holding a replica of content data, and to improve the accuracy as an index for measuring the popularity of content data.

[0016] Further, the node selecting means selects the node device from among the node devices that have transmitted the use request information.

In order to solve the above problem, according to another aspect of the present invention, there is provided a data sharing system including a plurality of node devices connected to each other via a network, and content usable in the plurality of node devices. A duplicate content data storage control device for controlling the storage of the duplicate content data in the data sharing system in which duplicate content data obtained by duplicating data is stored in any one or more of the node devices. , Value, and ratio information acquisition means for acquiring ratio information indicating a ratio according to information related to at least one of the attributes, and the number of copies of the content data based on the acquired ratio information A replica number determining means for determining the number of node devices corresponding to the determined replica number; Sending means, the storing request information for the previous SL selected node device indicating a storage request of the copy content data, use the copy content data from said plurality of node devices A copy content data storage control means for enabling storage.

[0018] Therefore, the number of copies is determined according to a ratio corresponding to information related to at least one of the popularity, value, and attribute of the content data, and the number of nodes corresponding to the number of copies is determined. Since the device is selected and the replicated content data (replica) is stored in the selected node device, the appropriate number of content data replicating power is assigned to each node device according to the degree of popularity. Can be retained. Therefore, since the processing amount of the node device is balanced, load concentration (access concentration) on a specific node device can be avoided.

[0019] Further, the copy number determination means determines the number obtained by multiplying the number of node devices participating in the data sharing system by multiplying the ratio as the copy number of the content data. And

[0020] Accordingly, each node device can hold an optimal number of replicas of content data in accordance with the degree of popularity or the like.

[0021] In addition, when the plurality of node devices are selected by the node selecting unit, the duplicate content data storage control unit is connected in a tree shape while the plurality of node devices form a plurality of hierarchies. The node device power of the upper layer constitutes a connection mode for sequentially transferring to the node device of the lower layer, and the storage request information including the connection mode information indicating the connection mode is included in the selected node It is characterized by being transmitted to the device.

[0022] Therefore, each node device can hold a replica of content data more efficiently.

[0023] In order to solve the above-described problem, according to still another aspect of the present invention, the node device receives the storage request information transmitted from the storage control device, according to the storage request information. A copy content data storage unit is provided for acquiring the content data, creating the copy content data, and storing the copy content data so that the plurality of node devices can be used.

[0024] In order to solve the above problem, according to still another aspect of the present invention, the node device transmits the use request information to the duplicate content data storage control device, After transmitting the use request information, the storage request information transmitted from the copy content data storage control device is received, the content data is acquired according to the storage request information, and the copy content data is created. And a copy content data storage unit for storing the content in a usable manner from the plurality of node devices.

[0025] In order to solve the above-mentioned problem, according to still another aspect of the present invention, the copy content data storage control device has the node that receives the storage request information including the connection mode information transmitted thereto. Node device power that is connected as a higher layer of the own device Acquires the transmitted content data and applies it to the node device connected as the lower layer of the self according to the connection mode information Content data to be transferred, and a copy content data storage unit that creates copy content data of the acquired content data and stores the copy content data so that the plurality of node devices can be used. .

[0026] In order to solve the above-described problem, according to still another aspect of the present invention, a data sharing system including a plurality of node devices connected to each other via a network and used in the plurality of node devices. In the data sharing system, duplicate content data obtained by duplicating possible content data is stored in any one or more of the node devices, and any one of the node devices is used to indicate a desired number of use of the content data. Based on the desired number-of-use information acquired, the number-of-replication determining means for determining the number of copies of the content data based on the acquired number-of-use information, and the determined number of copies Node selection means for selecting a corresponding number of node devices, and storage request information indicating a storage request for the duplicate content data for the selected node devices. A storage request information transmitting means for receiving, the selected node device receives the transmitted storage request information, acquires the content data according to the storage request information, and copies the copied content A copy content data storage unit that creates data and stores it in a usable manner from the plurality of node devices is provided.

[0027] In order to solve the above problem, according to still another aspect of the present invention, there is provided a data sharing system including a plurality of node devices connected to each other via a network, Which content data is duplicated content data that can be used on the node device?

A copy content data storage control method in the data sharing system stored in one or more of the node devices, wherein any one of the node devices obtains a desired usage number information indicating a desired usage number of the content data, A step of determining the number of copies of the content data based on the desired number-of-use information, and any one of the node devices selects a number of node devices corresponding to the determined number of copies; A step of transmitting storage request information indicating a request to store the content data to the selected node device; the selected node device receives the transmitted storage request information; and the storage request information Obtaining the content data, creating the duplicate content data, and storing the content data so that the plurality of node devices can be used; Characterized in that it comprises.

[0028] In order to solve the above-described problem, according to still another aspect of the present invention, a data sharing system including a plurality of node devices connected to each other via a network is used in the plurality of node devices. A computer that controls the storage of the replicated content data in the data sharing system in which the replicated content data copied from the possible content data is stored in any one or more of the node devices. Desired usage number information acquisition means for acquiring desired usage number information indicating the desired number, a replication number determination means for determining the number of copies of the content data based on the acquired desired usage number information, and the determined replication Node selection means for selecting a number of node devices corresponding to the number, and the duplicate content data for the selected node devices. Transmits the stored request information indicating a storage request, characterized in that to function the copy content data as copy content data storage control means for saving available from said plurality of node devices.

[0029] In order to solve the above-described problem, according to still another aspect of the present invention, a data sharing system including a plurality of node devices connected to each other via a network is used in the plurality of node devices. A computer that controls the storage of the replicated content data in the data sharing system in which the replicated content data is stored in any one or more of the node devices. A ratio information acquisition means for acquiring ratio information indicating a ratio according to information related to at least one of a value and an attribute, and based on the acquired ratio information, a copy of the content data A copy number determination means for determining the number of copies, a node selection means for selecting a number of node devices corresponding to the determined number of copies, and a storage request for the copy content data to the selected node device. It is characterized by transmitting storage request information and functioning as a copy content data storage control means for storing the copy content data in a usable manner from the plurality of node devices.

[0030] In order to solve the above-described problem, in still another aspect of the present invention, a computer included in the node device that receives the storage request information transmitted from the duplicate content data storage control device includes: According to the storage request 'information, the content data is acquired, the copy content data is created, and the copy content data is stored in a usable manner from the plurality of node devices. .

[0031] In order to solve the above-described problem, according to still another aspect of the present invention, the copy content data storage control processing program or the copy content data storage processing program is recorded in a computer-readable manner. Features.

The invention's effect

[0032] According to the present invention, the number of copies is determined according to the ratio according to the information related to the number of content data desired to be used or the popularity of the content data, and the number of node devices corresponding to the number of copies is selected. Thus, since the replicated content data (replica) is stored in the selected node device, each node device can hold an appropriate number of content data replicas according to the degree of popularity or the like. Can do. Therefore, since the processing amount of the node device is balanced, it is possible to avoid load concentration (access concentration) on a specific node device.

Brief Description of Drawings

FIG. 1 is a diagram showing a schematic configuration example in a data sharing system according to the present embodiment.

FIG. 2 is a diagram showing a schematic configuration example of a terminal device 1 according to the present embodiment.

[FIG. 3] (A) is a flowchart showing processing in the control unit 11 of the terminal device la for registering new content data, and (B) and (C) manage the pre-delivery content list. 6 is a flowchart showing processing in the control unit 11 of the terminal device lp as a pre-delivery content list management device, and (D) is a diagram showing a flowchart in the control unit 11 of the terminal device lb that requests the pre-delivery content list. (E) is a flowchart showing processing in the control unit 11 of the terminal device lq as a replica storage control device that controls the storage of replicas.

圆 4] (A) is a flowchart showing processing in the control unit 11 of the terminal device la that distributes newly registered content data, and (B) is a terminal device that creates and stores a replica lb FIG. 6C is a flowchart showing processing in the control unit 11 of the terminal device lr as a content list management device that manages content lists.

[5] FIG. 5 is a diagram illustrating an example of a connection mode for sequentially transferring content data from a terminal device 1 in an upper layer to a terminal device 1 in a lower layer.

[FIG. 6] (A) is a flowchart showing processing in the control unit 11 of the terminal device la for registering new content data, and (B) and (C) are pre-distribution managing the pre-distribution content lists. FIG. 7 is a flowchart showing processing in the control unit 11 of the terminal device lp as a content list management device, and (D) is a diagram showing a flowchart in the control unit 11 of the terminal device lb that requests a pre-delivery content list.

[FIG. 7] (A) is a flowchart showing processing in the control unit 11 of the terminal device lb for creating and storing a replica, and (B) is a terminal device as a replica storage control device for controlling replica storage. (c) is a flowchart showing a process in the control unit 11 of the terminal device la that distributes newly registered content data, and (D) is a content. 10 is a flowchart showing processing in the control unit 11 of the terminal device lr as a content list management device for managing a list.

[FIG. 8] (A) is a flowchart showing processing in the control unit 11 of the terminal device la that registers and distributes new content data, and (B) is a replica storage control device that controls storage of replicas. (C) is a flowchart showing the processing in the control unit 11 of the terminal device lb for creating and storing a replica, and (D) is the content Content list management for managing lists Flow chart showing processing in the control unit 11 of the terminal device lr as a device

FIG. 9 is a diagram showing an example of ratio information.

Explanation of symbols

[0034] 1 Terminal device

2 Internet

11 Control unit

12'1 B '| 5

13 Noffa memory

14 Decoder part

15 Video processor

16 Display

17 Audio processor

18 Speaker

19 Encoder section

20 Communications department

21 Input section

22 Bus

S data sharing system

BEST MODE FOR CARRYING OUT THE INVENTION

The best embodiment of the present invention will be described below with reference to the drawings. The embodiment described below is an embodiment when the present invention is applied to a data sharing system.

[0036] [1. Configuration of data sharing system, etc.]

First, the schematic configuration and functions of the data sharing system will be described with reference to FIG.

FIG. 1 is a diagram showing a schematic configuration example in the data sharing system according to the present embodiment.

[0038] As shown in FIG. 1, the data sharing system S includes terminal devices la to lr as node devices. (These terminal devices are called terminal devices that participate in the data sharing system s.) These are peer-to-peer (P2P) that can be connected to each other via the Internet 2 as a network. ) Network system. Each terminal device is assigned a unique serial number and an IP (Internet Protocol) address. In the following description, when one or more terminal devices among the terminal devices la to lr are indicated, they may be referred to as “terminal device 1” for convenience.

[0039] In such a data sharing system S, various content data that can be used by the plurality of terminal devices la to lr are distributed and stored in the plurality of terminal devices 1. . For example, the terminal device la stores the content data of the movie with the title XXX, while the terminal device lb stores the content data of the movie with the title YYY.

[0040] Furthermore, in the data sharing system S, the copy content data (hereinafter referred to as "replica") that can be used by a plurality of terminal devices la to lr is one of one or more terminal devices 1 The appropriate number is stored. For example, content data newly stored in a certain terminal device 1 is distributed to another terminal device 1, where a replica is created and stored.

[0041] Note that, for example, a large number of replicas are created for content data that is popular and frequently used (in other words, access frequency), and these replicas are stored in many terminal devices 1. Such a replica desirably has the same data (file) configuration as the master content data and has the same quality. In addition, since the replica has the same quality as the master, there is no need for a master-slave relationship between the replica and the master. For example, even if the master is deleted, if a replica of the same content exists, the replica may be allowed to behave as the master thereafter.

[0042] The content data and replicas stored in the plurality of terminal devices 1 are stored in this manner!

(That is, the content list indicating the power stored in which terminal device 1 can be obtained in all the terminal devices la to lr. For example, each terminal device 1 is in the neighborhood (for example, the number of HOPs is (Predetermined number) of the IP addresses of the terminal devices 1 are recognized, and the content list is acquired by communicating with the neighboring terminal device 1 according to the IP address This will spread throughout the data sharing system s (that is, newly generated or updated content lists are transmitted in a passing format). In this content list, for example, information about content data or replicas (for example, content ID (identification information), title, and IP address of the terminal device 1 that stores the content data or replica), etc., (Hereinafter referred to as “content information”).

[0043] At least one terminal device 1 among the terminal devices la to lr functions as a replica storage control device (replication content data storage control device) that controls storage of the replica in the data sharing system S. In addition, at least one terminal device 1 functions as a content list management device for managing the content list! /. Furthermore, although it is optional, any one of the terminal devices 1 is content data newly registered (saved) in the system S, that is, information related to content data before distribution (for example, content data content ID (identification information) ), Title, content, and IP address of the terminal device 1 that stores the content data), etc., hereinafter “pre-delivery content information”, etc.) Functions as a content list management device.

Next, with reference to FIG. 2, a schematic configuration and the like of the terminal device 1 will be described.

FIG. 2 is a diagram illustrating a schematic configuration example of the terminal device 1 according to the present embodiment.

As the terminal device 1, for example, a personal computer or a receiver with an STB (Set Top Box) can be applied. As shown in FIG. 2, a CPU having a calculation function, a working RAM, various data and ROM, etc., that stores the program The configured control unit 11, the content data or replica, and further the storage unit 12 that consists of an HDD etc. for storing and storing (storing) the program, etc., and the received content data Alternatively, a noffer memory 13 for temporarily storing a replica, and a decoder unit 14 for decoding (data decompression, decoding, etc.) encoded video data (video information) and audio data (audio information) included in the content data or replica The video processing unit 15 that performs a predetermined drawing process on the decoded video data and outputs the video signal, and the video processing unit 15 Display unit such as CRT or liquid crystal display that displays video based on the output video signal 1 6 and the audio processing unit 17 that converts the decoded audio data into an analog audio signal by D (Digital) / A (Analog) conversion, and then amplifies it by an amplifier, and outputs the audio data from the audio processing unit 17 A speaker 18 that outputs an audio signal as a sound wave, an encoder unit 19 that encodes video data, audio data, and the like included in content data or a replica, and other terminal devices 1 through the Internet 2 A communication unit 20 for communicating with the control unit 11 and an input unit that receives an instruction from the user and gives an instruction signal corresponding to the instruction to the control unit 11 (for example, a keyboard, a mouse, or an operation panel) The control unit 11, the storage unit 12, the notch memory 13, the decoder unit 14, the encoder unit 19, and the communication unit 20 They are connected to each other through the scan 22.

[0047] Then, the CPU in the control unit 11 executes the program stored in the storage unit 12 or the like (including the duplicate content data storage control processing program and the duplicate content data storage processing program of the present invention), thereby the control unit 11 Controls transmission / reception of content data or replica, and playback output of content data or replica (that is, playback output through decoder unit 14, video processing unit 15, display unit 16, audio processing unit 17, and speaker 18) Furthermore, each process described below is performed to function as each means in the present invention (details of each means will be described later). Note that the program may be downloaded from a predetermined server on the Internet 2, for example, recorded on a recording medium such as a CD-ROM, and read via a drive of the recording medium. You may do it.

[0048] [2. Operation of data sharing system]

Next, the operation of the data sharing system S will be described separately for the first to third embodiments.

[0049] (First embodiment)

First, the operation of the data sharing system S according to the first embodiment will be described with reference to FIGS. 3 to 5 and the like.

FIG. 3 (A) is a flowchart showing processing in the control unit 11 of the terminal device la that registers new content data. FIGS. 3 (B) and 3 (C) manage the pre-delivery content list. FIG. 3D is a flowchart showing processing in the control unit 11 of the terminal device lp as the pre-delivery content list management device, and FIG. FIG. 3E is a flowchart showing processing in the control unit 11 of the terminal device lq as a replica storage control device that controls storage of replicas.

FIG. 4 (A) is a flowchart showing processing in the control unit 11 of the terminal device la that distributes newly registered content data, and FIG. 4 (B) creates a replica. FIG. 4 (C) is a flowchart showing processing in the control unit 11 of the terminal device lr as a content list management device for managing the content list.

First, in the process shown in FIG. 3A in the terminal device la, the control unit 11 stores new content data in the storage unit 12 in accordance with an instruction from the user via the input unit 21, for example. Save (register) (step S1), transmit the content information before distribution of the content data to the terminal device lp via the communication unit 20 and the Internet 2 (step S2), and terminate the processing.

[0053] It should be noted that all the terminal devices la to lr acquire the IP address of the terminal device lp as the pre-delivery content list management device in advance (for example, from the neighboring terminal device 1), Based on the IP address, the pre-delivery content information is sent to the terminal device lp.

[0054] On the other hand, the control unit 11 of the terminal device lp receives the pre-delivery content information transmitted from the terminal device la in the process shown in FIG. The previous content blueprint is added to the previous content list, that is, the previous content list is updated (step S4), and the process ends.

Next, in the process shown in FIG. 3D in the terminal device lb, the control unit 11 performs list request information for requesting a pre-delivery content list, for example, according to an instruction from the user via the input unit 21. Is transmitted to the terminal device lp via the communication unit 20 and the Internet 2 (step S5), and is waited for reception (step S6).

[0056] On the other hand, the control unit 11 of the terminal device lp performs the terminal device in the process shown in FIG. The list request information that has also been transmitted is received (step S7), the pre-distribution content list is transmitted to the terminal device lb via the communication unit 20 and the Internet 2 (step S8), and the process ends. To do.

[0057] On the other hand, the control unit 11 of the terminal device lb receives the pre-delivery content list transmitted from the terminal device lp (step S6: Y), and displays it on the display unit 16, for example, to display the user list. (Step S9) and prompts the user to enter whether or not he / she wants to use (view) the content data shown in the pre-delivery content list. When the user force is also input via the input unit 21, the control unit 11 of the terminal device lb determines whether or not the input is a force that the content data is desired to be used (step S 10 If the input is desired input (step S 10: Y), the usage request information indicating the desired use of the content data is transmitted to the terminal device lq via the communication unit 20 and the Internet 2 (step S 10: Y). S11) If the input is not desired to be used (step S10: N), the process is terminated without transmitting the desired usage information.

Note that the IP address of the terminal device lq as the replica storage control device is described in, for example, the pre-delivery content list, and the terminal device lb can recognize the IP address of the terminal device lq. ing. In addition, the use request information includes content information before distribution of the corresponding content data.

Next, the control unit 11 of the terminal device lq receives (accepts) the use request information transmitted from the terminal device lb force in the process shown in FIG. (Step S12: Y), the IP address of the terminal device lb that has transmitted the use request information is used as a use request terminal list (generated and stored in the storage unit 12 for the content data indicated in the use request information). (Step S13).

[0060] Next, the control unit 11 of the terminal device lq determines whether or not a preset reception period (predetermined period: for example, one week) has elapsed (step S14). In other words, until the acceptance period elapses, use request information from a plurality of terminal devices 1 is received, and the number of terminal devices registered in the use request terminal list gradually increases.

[0061] Then, when the acceptance period has elapsed (step S14: Y), acceptance of the desired use information is terminated, and the control unit 11 uses the desired use information as means for obtaining desired use number information. By calculating (that is, adding up the number of IP addresses registered in the desired use terminal list), the desired use number of the content data is calculated and obtained as desired use number information (step S15).

[0062] Next, the control unit 11 of the terminal device lq determines the number of copies of the content data based on the acquired desired number-of-uses information as copy number determination means (step S16). For example, the number of copies equal to the desired number of uses is determined, or the ratio between the desired number of use and the number of terminal devices 1 participating in the data sharing system S (number of participation) (for example, participation) Number: The number of replicas is determined based on the number of replicas = 10: 1). Such a ratio may be set in advance in the terminal device 1 q, or information such as the popularity, value, and attributes of the content data (such information is included in the pre-distribution content information in the above-mentioned use desired information, for example). It may be set (changes) according to (included). For example, compared to popular content data that has a large amount of distribution revenue, such as movie content data, or popular content data that has a high audience rating and content data of programs that have been broadcast on the TV in the past. Is set so that the ratio of the number of replicas is large (for example, the number of participants: the number of replicas = 5: 2). Note that the method for determining the number of copies of content data may be determined by other methods that are not limited to these. Further, the number of terminal devices 1 participating in the data sharing system S is periodically collected and recognized by the terminal device lq.

[0063] Next, the control unit 11 of the terminal device lq selects a number of terminal devices corresponding to the determined number of replicas as node selection means (step S17). For example, the medium power of the terminal device 1 that transmitted the use request information The terminal devices 1 corresponding to the determined number of copies are selected at random, or selected in preference to those that transmitted the use request information earlier. .

[0064] Note that the node selection means by the control unit 11 does not need to directly select a terminal device, but is node selection information such as a storage probability at which a copy of content data is stored in each terminal device. Also good. In this case, the node selection information is transmitted to an arbitrary terminal device, and each terminal device that has received the node selection information autonomously determines from the node selection information whether or not the content data is stored. A terminal device that stores a copy of the content data is selected. [0065] Next, the control unit 11 of the terminal device lq connects the plurality of selected terminal devices 1 in a tree shape while forming a plurality of layers, and the content data is transmitted from the terminal device 1 in the upper layer to the lower layer. A connection mode for sequentially transferring to the terminal device 1 is configured, and connection mode information indicating the connection mode is generated (step S18).

FIG. 5 is a diagram illustrating an example of a connection mode for sequentially transferring content data from the upper layer terminal apparatus 1 to the lower layer terminal apparatus 1. The connection mode shown in the example of FIG. 5 is an overlay network configured on the premise of the actual network shown in FIG. 1, and specifies the distribution route of content data.

[0067] Next, the control unit 11 of the terminal device lq serves as a replica content data storage control means for the plurality of selected terminal devices 1 (here, the terminal devices lb to lo are selected) to store replicas. Distribution request information (including the generated connection mode information) and a blueprint indicating the size of the content data are distributed to the terminal device la storing the content data. Distribution request information indicating the request (including the generated connection mode information) is transmitted via the communication unit 20 and the Internet 2 (step S 19), and the process is terminated. As a result, the terminal device lq causes the terminal devices lb to lo to store the replicas so that they can be used from the plurality of terminal devices 1.

[0068] On the other hand, for example, the control unit 11 of the terminal device lb (the same applies to the other terminal devices lc to lo) uses the storage request transmitted from the terminal device lq in the process shown in FIG. The information and the information indicating the size of the content data are received (step S21), and the content data or replica that has already been stored and saved until the free space of the content data size is secured (recorded date and time) ) Are deleted from the storage unit 12 in order (step S22).

On the other hand, the control unit 11 of the terminal device la receives the distribution request information transmitted from the terminal device lq in the process shown in FIG. 4 (A) (step S31), and the connection mode included in this According to the information, distribution of the newly registered content data is started to the terminal device 1 (step S32). For example, as shown in FIG. 5, the content data is distributed (transmitted) to the terminal devices lb and lc connected immediately below the terminal device la. It becomes.

[0070] On the other hand, for example, the control unit 11 of the terminal device lb uses the content of the terminal device la (terminal device connected as its own upper layer) in the process shown in FIG. 4B. Is received (Step S23: Y), acquired, and stored as a copy content data storage means in the notch memory 13, and the replica can be created and used from multiple node devices 1. It is stored and saved in the storage unit 12 so as to become (step S24).

[0071] Further, the control unit 11 of the terminal device lb serves as content data transfer means for connecting the content data stored in the buffer memory 13 as its lower hierarchy according to the connection mode information. Transfer (send) to e (step S 25), and terminate the process. In this way, the content data distributed from the terminal device la is sequentially transferred from the upper layer terminal device 1 to the lower layer terminal device 1 according to the connection mode information, and in each terminal device 1 that has received the content data. A replica is created and stored so that it can be used from a plurality of terminal devices 1.

On the other hand, when the control unit 11 of the terminal device la determines that the distribution of the content data is completed in the process shown in FIG. 4A (step S33: Y), the content information ( For example, the content ID (identification information), the title, and the content data or replica (for example, including the IP addresses of the terminal devices la to lo) are transmitted to the terminal device lr via the communication unit 20 and the Internet 2 ( In step S34), the process is terminated.

[0073] Note that the terminal device la acquires the IP address of the terminal device lr as the content list management device in advance (for example, from the neighboring terminal device 1), and based on the IP address Content information is transmitted to the terminal device lr.

[0074] On the other hand, the control unit 11 of the terminal device lr receives the content information transmitted from the terminal device la in the process shown in FIG. 4C (step S41), and the content information Is added to the content list, that is, the content list is updated (step S42), and the process is terminated.

[0075] In this way, an appropriate number of replicas of content data are stored in a plurality of terminal devices 1, and each terminal device 1 obtains the content list and refers to it, thereby obtaining The replica can be downloaded from the desired terminal device 1 and used.

[0076] As described above, according to the first embodiment, the number of copies corresponding to the desired number of content data is determined, the number of terminal devices 1 corresponding to the number of copies is selected, Since the plurality of selected terminal devices 1 are configured to store replicas, it is possible to cause each terminal device 1 to hold an appropriate number of replicas of content data according to the degree of popularity and the like. Therefore, since the processing amount of each terminal device 1 is balanced, load concentration (access concentration) on a specific terminal device 1 can be avoided.

[0077] Further, in the configuration in which the number of replicas is determined based on the ratio between the desired number of use and the number of terminal devices 1 participating in the data sharing system S (participation number), the entire data sharing system S The optimal number of replicas can be created and saved.

[0078] Furthermore, since the content data is distributed according to the connection mode for sequentially transferring the content data from the upper layer terminal device 1 to the lower layer terminal device 1, the replica is created and stored. Each terminal device 1 can hold a replica of content data more efficiently.

[0079] (Second Embodiment)

First, the operation of the data sharing system S according to the second embodiment will be described with reference to FIG. 6 and FIG. This second embodiment is basically the same as the first embodiment, and is an embodiment that focuses on the prior delivery of force content data.

FIG. 6 (A) is a flowchart showing processing in the control unit 11 of the terminal device la for registering new content data, and FIGS. 6 (B) and 6 (C) manage the pre-delivery content list. FIG. 6D is a flowchart showing processing in the control unit 11 of the terminal device lp as the pre-delivery content list management device, and FIG. 6D is a diagram showing a flowchart in the control unit 11 of the terminal device lb that requests the pre-delivery content list. is there.

FIG. 7A is a flowchart showing processing in the control unit 11 of the terminal device lb that creates and stores a replica, and FIG. 7B is a replica storage that controls storage of the replica. FIG. 7C is a flowchart showing processing in the control unit 11 of the terminal device la that distributes newly registered content data. FIG. 7C is a flowchart showing processing in the control unit 11 of the terminal device lq as the control device. Yes, Figure 7 (D) manages the content list 10 is a flowchart showing processing in a control unit 11 of a terminal device lr as a content list management device.

In the second embodiment, the processes shown in FIGS. 6A to 6C are the same as the processes shown in FIGS. 3A to 3C in the first embodiment. Therefore, the explanation is omitted.

[0083] In the process shown in Fig. 6 (D) in the terminal device lb, the control unit 11 sends, for example, list request information for requesting a pre-distribution content list in accordance with an instruction from the user via the input unit 21. And the terminal device lp is transmitted to the terminal device lp via the Internet 2 (step S55). On the other hand, the pre-delivery content list to which the terminal device lp force has also been transmitted is received (step S56), and the processing is terminated.

Here, for the second embodiment, the pre-delivery content information described in the pre-delivery content list describes the pre-delivery date and time of the content data, and the pre-delivery date and time of the pre-delivery content date. For example, when a few hours ago, the process shown in FIG. 7A is started in the terminal device lb, and the pre-delivery content list is displayed on the display unit 16 for example and presented to the user (step S59). Prompts the user whether to use (view) the content data shown in the content list. When the user force is also input via the input unit 21, the control unit 11 of the terminal device lb determines whether or not the input is a force that desires to use the content data (step S60). If the input is a request for use (step S60: Y), use request information indicating the use of the content data is transmitted to the terminal device lq via the communication unit 20 and the Internet 2 (step S61). ), Waiting to receive storage request information (step S71). On the other hand, if the input is not desired to be used (step S60: N), the processing is terminated without transmitting the usage request information.

[0085] On the other hand, the control unit 11 of the terminal device lq receives (accepts) the use request information transmitted from the terminal device lb force as the use request information receiving means in the process shown in FIG. 7 (B). ) And (step S62), the IP address of the terminal device lb that transmitted the use request information is registered in the use request terminal list (step S63).

[0086] Next, the control unit 11 of the terminal device lq determines whether or not the predecessor delivery date / time set in advance is reached. Is determined (step S64). In other words, the terminal device lq waits until the date and time of the prior delivery of the content data, and during this time, the use request information from the plurality of terminal devices 1 is accepted and gradually registered in the use terminal list. The number of terminal devices to be increased will increase.

[0087] Then, when the preceding delivery date / time is reached (step S64: Y), the acceptance of the desired use information is terminated, and, as in the first embodiment, the control unit 11 serves as a desired use number information obtaining unit. Calculate the desired number of use of the content data by totaling the above-mentioned desired use information (that is, totaling the number of IP addresses registered in the desired terminal list), and obtain this as the desired number of use information ( Step S65).

[0088] Next, the control unit 11 of the terminal device lq determines the number of copies of the content data (for example, the number of copies equal to the desired number of uses) based on the acquired desired number of uses information as a copy number determination means. (Step S66). Note that the method for determining the number of copies of content data is the same as in the first embodiment.

Next, similarly to the first embodiment, the control unit 11 of the terminal device lq selects a number of terminal devices corresponding to the determined number of replicas as a node selection unit (step S67).

[0090] Next, similarly to the first embodiment, the control unit 11 of the terminal device lq connects the plurality of selected terminal devices 1 in a tree shape while forming a plurality of hierarchies, and the content data of the upper layer A connection mode for sequentially transferring from the terminal device 1 to the lower-layer terminal device 1 is configured, and connection mode information indicating the connection mode is generated (step S68).

Next, similarly to the first embodiment, the control unit 11 of the terminal device lq serves as a copy content data storage control unit, and stores a storage request indicating a replica storage request to the plurality of selected terminal devices 1. Information (including the generated connection mode information) and information indicating the size of the content data, indicating the distribution request of the content data to the terminal device la that stores the content data! The distribution request information (including the generated connection mode information) is transmitted via the communication unit 20 and the Internet 2 (step S69), and the process ends.

[0092] It should be noted that the distribution request information includes content data and its replica for terminal devices 1 other than the terminal device 1 that transmitted the usage request information (particularly, the terminal device 1 that creates a replica). Therefore, the control unit 11 of the terminal device lq uses the usage restriction period, the content data, and the use of the replica thereof as a usage restriction means. Viewing) will be restricted.

[0093] On the other hand, for example, the control unit 11 of the terminal device lb (the same applies to the other terminal devices lc to lo) uses the terminal device lq in the process shown in FIG. 7A as in the first embodiment. The storage request information and the information indicating the size of the content data transmitted from step S71 are received (step S71), and the content data or replica that has been stored and stored until the free space of the content data size is secured. Are deleted from the storage unit 12 in order from the oldest storage date (recording date) (step S72).

On the other hand, the control unit 11 of the terminal device la receives the distribution request information transmitted from the terminal device lq in the process shown in FIG. 7C (step S81), as in the first embodiment. Pre-delivery of the newly registered content data is started to the terminal device 1 in accordance with the connection mode information included therein (step S82). For example, as shown in FIG. 5, the content data is distributed (transmitted) to the terminal devices lb and lc connected immediately below the terminal device la by, for example, the streaming method.

[0095] On the other hand, for example, the control unit 11 of the terminal device lb uses the content data distributed in the terminal device la (terminal device connected as its own upper layer) in the process shown in FIG. Is received (step S73), acquired and stored in the buffer memory 13 while the content data is transmitted through the decoder unit 14, the video processing unit 15, the display unit 16, the audio processing unit 17 and the speaker 18. Then, the replica is created as a copy content data storage means, and stored in the storage unit 12 so as to be usable from the plurality of node devices 1 (step S 74).

[0096] In addition, as in the first embodiment, the control unit 11 of the terminal device lb uses the content data stored in the buffer memory 13 as a content data transfer unit according to the connection mode information. Are transferred (transmitted) to the node devices d and e connected as (step S75), and the process ends. Thus, the content data distributed in advance from the terminal device la is sequentially transferred from the upper layer terminal device 1 to the lower layer terminal device 1 according to the connection mode information, and each terminal that has received the content data. In addition to being reproduced and output by the device 1, a replica is created and stored in a usable manner from a plurality of terminal devices 1.

On the other hand, when the control unit 11 of the terminal device la determines that the preceding distribution of the content data has been completed in the process shown in FIG. 7C (step S83: Y), the use included in the distribution request information is used. It is determined whether or not a limited period (for example, one week) has elapsed (step S84). If the usage limit period has elapsed (step S84: Y), the content of the content data that has been pre-delivered. Information (for example, content ID (identification information), title, and content data or replicas including the IP addresses of the terminal devices la to lo, etc.) is transmitted to the terminal device lr via the communication unit 20 and the Internet 2. (Step S85), the process is terminated.

[0098] It should be noted that the usage restriction period may be an arbitrary power. For example, the usage restriction period may be set (changes) according to information such as popularity, value, and attribute of content data.

[0099] On the other hand, the control unit 11 of the terminal device lr receives the content information transmitted from the terminal device la in the process shown in FIG. 7D (step S91), and the content information The content list is updated based on (Step S92), and the process ends.

[0100] In this way, an appropriate number of content data replicas are stored in a plurality of terminal devices 1. However, during the above-mentioned usage restriction period, the content information of the content data for which the preceding distribution has been completed is included in the content list. Since it is not registered, content data and the use (viewing) power S of the replica are restricted for terminal devices 1 other than the terminal device 1 that has created and stored the replica. In other words, the content data is pre-delivered in return for providing the storage capacity for storing the replica.

[0101] As described above, according to the second embodiment, in addition to the same effects as in the first embodiment, in addition to requesting the prior delivery of content data, the advance delivery is desired. Since the replica is stored in the terminal device 1 to be used and the terminal device 1 other than the terminal device 1 is configured to restrict the use (viewing) of the content data and its replica, the use value of the preceding distribution is increased. In addition, the accuracy as an index for measuring the popularity of content data can be improved.

[0102] (Third embodiment) Next, the operation of the data sharing system S according to the third embodiment will be described with reference to FIGS. In the third embodiment, the number of copies of content data is determined based on ratio information indicating a ratio according to information related to at least one of popularity, value, and attribute of the content data. Embodiment.

FIG. 8 (A) is a flowchart showing processing in the control unit 11 of the terminal device la that registers and distributes new content data, and FIG. 8 (B) is a replica that controls the storage of replicas. FIG. 8C is a flowchart showing processing in the control unit 11 of the terminal device lb that creates and stores a replica. FIG. 8D is a flowchart showing processing in the control unit 11 of the terminal device lr as a content list management device for managing the content list.

First, in the process shown in FIG. 8A in the terminal device la, the control unit 11, for example, in accordance with an instruction from the user via the input unit 21, new content data and the content data. Is stored and saved (registered) in the storage unit 12 (step S101).

FIGS. 9A and 9B are diagrams showing an example of the ratio information. In the example of Fig. 9 (A), the distribution revenue of content data (movie content) (for example, information related to the popularity of content data) and the proportion 51 according to the distribution revenue are shown, and the distribution revenue is high. The ratio is getting bigger. In the example of FIG. 9 (B), the audience rating of content data (TV program content) (for example, information related to the popularity of content data) and the ratio 52 corresponding to the audience rating are shown. The higher the audience rating, the greater the percentage.

[0106] Next, the control unit 11 of the terminal device la transmits the ratio information of the registered content data to the terminal device lq via the communication unit 20 and the Internet 2 (step S102), and the distribution request information Waiting for reception (step S121).

[0107] On the other hand, the control unit 11 of the terminal apparatus lq receives the ratio information of the content data transmitted from the terminal apparatus la in the process shown in FIG. S103), this is obtained, and the number of copies of the content data is determined based on the ratio information as copy number determination means (step S104). For example, the above-mentioned percentage is divided into the number of participation of terminal device 1 participating in data sharing system S (for example, 1,000,000 units). The number (eg, 400,000) obtained by multiplying the ratio indicated by the combined information (for example, the ratio “0.4” shown in FIG. 9A) is determined as the number of copies of the content data. In other words, content data with a higher ratio will create more replicas. This power / ratio information can be combined with usage frequency prediction information! /.

[0108] The ratio information is not limited to this, and various other parameters can be considered. For example, it may be information related to a combination of popularity, value, and attributes. Examples of information related to the value of content data include the price of the content data itself and the expert evaluation index. Examples of information related to the attribute of content data include the genre of content data (for example, sports, drama, movie, music, variety, etc.).

[0109] Next, the control unit 11 of the terminal device lq selects a number of terminal devices corresponding to the determined number of replicas as node selection means (step S105). For example, among the terminal devices 1 participating in the data sharing system S, the terminal devices 1 corresponding to the determined number of copies are randomly selected. It is assumed that the terminal device lq recognizes the IP address of the terminal device 1 participating in the data sharing system S.

[0110] Next, as in the first embodiment, the control unit 11 of the terminal device lq connects the plurality of selected terminal devices 1 in a tree shape while forming a plurality of hierarchies, and the content data of the upper layer A connection mode for sequentially transferring from the terminal device 1 to the lower-layer terminal device 1 is configured, and connection mode information indicating the connection mode is generated (step S106).

[0111] Next, the control unit 11 of the terminal device lq serves as copy content data storage control means, storage request information indicating a replica storage request to the plurality of selected terminal devices 1 (the generated connection mode). Information) and distribution request information indicating the content data distribution request to the terminal device la storing the content data (the generated connection mode information is Are included) via the communication unit 20 and the Internet 2 (step S107), and the process is terminated.

On the other hand, for example, the control unit 11 of the terminal device lb indicates the size of the storage request information and the content data transmitted from the terminal device lq in the process shown in FIG. 8C. Information is received (step S108). Note that the processing in steps S109 to S112 shown in FIG. 8C is the same as the processing in steps S22 to S25 shown in FIG. 4B in the first embodiment, and therefore redundant description is omitted.

On the other hand, the control unit 11 of the terminal device la receives the distribution request information transmitted from the terminal device lq in the process shown in FIG. 8A (step S121). Note that the processing in steps S122 to S124 shown in FIG. 8 (A) is the same as the processing in steps S32 to S34 shown in FIG. 4 (A) in the first embodiment, and a duplicate description will be omitted. Further, the processing in steps S131 and S132 shown in FIG. 8D is the same as the processing in steps S41 and S42 shown in FIG.

[0114] As described above, according to the third embodiment, the ratio according to information related to at least one of popularity, value, and attribute of content data (for example, distribution revenue, viewing, etc.) The number of replicas corresponding to the number of replicas is determined, the number of terminal devices 1 corresponding to the number of replicas is selected, and the selected terminal device 1 is configured to store replicas. Accordingly, it is possible to maintain an appropriate number of replicas of content data in each node device. Therefore, since the processing amount of each terminal device 1 is balanced, load concentration (access concentration) on a specific terminal device 1 can be avoided.

[0115] The present invention is not limited to the above embodiment. The above embodiment is merely an example, and the present invention has the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

[0116] In addition, the entire disclosure of the Japanese patent application (No. 2004-348602) including the specification, claims, drawings and abstract filed on December 1, 2004 refers to all of them So it is incorporated here.

Claims

The scope of the claims

[1] A data sharing system including a plurality of node devices connected to each other via a network, and at least one copy content data obtained by duplicating content data usable by the plurality of node devices A copy content data storage control device for controlling storage of the copy content data in the data sharing system stored in the node device,

Use desired number information obtaining means for obtaining desired use number information indicating the desired use number of the content data;

Copy number determining means for determining the copy number of the content data based on the acquired desired use number information;

Node selection means for selecting a number of node devices corresponding to the determined number of replicas, and storage request information indicating a request for storing the replicated content data to the selected node devices, and the replicated content Duplicate content data storage control means for storing data available from the plurality of node devices;

A copy content data storage control device comprising:

[2] In the copy content data storage control device according to claim 1,

A node device that desires to use the content data, further comprising use request information receiving means for receiving use request information indicating the transmitted use hope,

The desired number-of-use information acquisition means acquires the above-mentioned desired number-of-use information by aggregating the desired-use information, and a duplicate content data storage control device characterized in that

[3] In the copy content data storage control device according to claim 2,

The copy content data storage control device, wherein the use request information receiving means receives the use request information only for a predetermined period.

[4] In the copy content data storage control device according to any one of claims 1 to 3,

The copy number determination means determines the copy number of the content data based on a ratio between the desired use number and the number of node devices participating in the data sharing system. A duplicate content data storage control device characterized by the above.

[5] In the copy content data storage control device according to claim 2,

A duplicate content data storage control device, further comprising: a use restriction unit that restricts the use of the content data and the duplicate content data for a predetermined period to a node device other than the node device that has transmitted the use request information. .

[6] In the duplicate content data storage control device according to claim 2,

The duplicate content data storage control device, wherein the node selection means selects the node device from among the node devices that have transmitted the use request information.

[7] A data sharing system including a plurality of node devices connected to each other via a network, and at least one copy content data obtained by copying content data that can be used by the plurality of node devices. A copy content data storage control device for controlling storage of the copy content data in the data sharing system stored in the node device,

Ratio information acquisition means for acquiring ratio information indicating a ratio according to information related to at least one of popularity, value, and attribute of the content data, and based on the acquired ratio information A copy number determination means for determining the number of copies of content data;

A copy content data storage control device comprising:

[8] In the copy content data storage control device according to claim 7,

The copy number determination means participates in the data sharing system! A duplicate content data storage control device characterized in that the number obtained by multiplying the number of node devices to be multiplied by the ratio is determined as the number of duplicates of the content data.

[9] In the copy content data storage control device according to claim 1,

The duplicate content data storage control means is configured to receive a plurality of nodes by the node selection means. When a node device is selected, the plurality of node devices are connected in a single line while forming a plurality of layers, and the content data is sequentially transferred from the node device in the upper layer to the node devices in the lower layer. Copy content data storage control comprising a connection mode for transfer and transmitting the storage request information including connection mode information indicating the connection mode to the selected node device apparatus.

[10] The copy content data storage control device according to claim 1, wherein the node device receives the storage request information transmitted.

A node device comprising: copy content data storage means for acquiring the content data in accordance with the storage request information, creating the copy content data, and storing the content data in a usable manner from the plurality of node devices.

[11] The node device that transmits the use request information to the duplicate content data storage control device according to claim 2,

After transmitting the use request information, the storage request information transmitted from the copy content data storage control device is received, the content data is acquired according to the storage request information, and the copy content data is created. And a duplicate content data storage unit that stores the content in a usable manner from the plurality of node devices.

[12] The duplicate content data storage control device according to claim 9, wherein the node device receives the storage request information including the connection mode information transmitted thereto, and is connected as its own upper layer. Content data transfer means for acquiring the content data transmitted from the node device and transferring it to the node device connected as its own lower layer according to the connection mode information;

Duplicate content data storage means for creating duplicate content data of the acquired content data and storing the duplicated content data so as to be usable by the plurality of node devices;

A node device comprising:

[13] A data sharing system including a plurality of node devices connected to each other via a network, wherein the content data that can be used by the plurality of node devices is duplicated in any one or more of the content data The data sharing system stored in the node device And

Any of the node devices

Node selection means for selecting a number of node devices corresponding to the determined number of copies, and storage request information transmission means for transmitting storage request information indicating a storage request for the copy content data to the selected node devices. And comprising

The selected node device is:

A copy that receives the storage request information that has been transmitted, acquires the content data according to the storage request information, creates the copy content data, and stores the copy content data in a usable manner from the plurality of node devices. A data sharing system characterized by comprising content data storage means.

A data sharing system comprising a plurality of node devices connected to each other via a network, wherein the content data that can be used by the plurality of node devices is one or more duplicate content data A copy content data storage control method in the data sharing system stored in a device, comprising:

Any one of the node devices obtains desired use number information indicating the desired use number of the content data, and determines the number of copies of the content data based on the desired use number information;

Any one of the node devices selects a number of node devices corresponding to the determined number of copies, and transmits storage request information indicating a storage data storage request to the selected node device. Process,

The selected node apparatus receives the transmitted storage request information, acquires the content data in accordance with the storage request information, creates its duplicate content data, and uses the content data as the plurality of node apparatuses. The process of storing it available from

A copy content data storage control method comprising: [15] A data sharing system including a plurality of node devices connected to each other via a network, wherein the content data that can be used by the plurality of node devices is duplicated in any one or more of the content data A computer for controlling storage of the duplicate content data in the data sharing system stored in a node device;

Use desired number information obtaining means for obtaining desired use number information indicating a desired use number of the content data;

Copy number determination means for determining the copy number of the content data based on the acquired desired use number information;

Node selection means for selecting a number of node devices corresponding to the determined number of replicas, and

Functions as copy content data storage control means for transmitting storage request information indicating a storage request for the copy content data to the selected node device, and storing the copy content data to be usable from the plurality of node devices. A copy content data storage control processing program characterized by

[16] A data sharing system including a plurality of node devices connected to each other via a network, wherein the content data that can be used by the plurality of node devices is one or more duplicate content data A computer for controlling storage of the duplicate content data in the data sharing system stored in a node device;

Ratio information acquisition means for acquiring ratio information indicating a ratio according to information related to at least one of popularity, value, and attribute of the content data;

A copy number determining means for determining the copy number of the content data based on the acquired ratio information;

Functions as copy content data storage control means for transmitting storage request information indicating a storage request for the copy content data to the selected node device, and storing the copy content data to be usable from the plurality of node devices. A copy content data storage control processing program characterized by [17] A computer included in the node device that receives the storage request information transmitted from the duplicate content data storage control device according to claim 1, acquires the content data according to the storage request information, A duplicate content data storage processing program that creates the duplicate content data and causes it to function as a duplicate content data storage unit that can be used from the plurality of node devices.

[18] A recording medium in which the copy content data storage control processing program according to claim 15 or 16 or the copy content data storage processing program according to claim 17 is recorded so as to be readable by a computer. .