JP2009031894A - Content distribution system, content distribution program for management server, and content distribution program for client - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly and efficiently distribute large capacity of data under unitary management to a plurality of users. <P>SOLUTION: A management server 10 stores distribution schedule, distribution control information, supplier information, and the address information of a client 20. A client 20A specifies content data to be distributed based on feed information acquired from the management server 10, and acquires the distribution control information and supplier information of the content data from the management server 10, and notifies a management server 10 of the download start of the content data whose request destination has been specified. The management server 10 notifies a client 20B as the request destination of inter-peer communication information (address information) with the client 20A. The client 20B transmits the fragmented content data to the client 20A based on the inter-peer communication information. The client 20A checks reception data, and requests retransmission when the reception data are imperfect, and stores the reception data when perfect. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a data distribution technique for distributing data such as files and contents managed by a server via a network. More specifically, the present invention relates to a hybrid peer-to-peer content distribution system and a management server / client content distribution program in which a management server manages data distribution and distributes data from the management server to clients or between clients.

As a mechanism for efficiently distributing data to users connected to a network, a data distribution system using a peer-to-peer network is known. In a peer-to-peer network, a user connected to the network functions as both a client and a server. For example, as shown in Patent Document 1, in a peer-to-peer data distribution system, a user makes a file request to another user as a client, and in some cases, receives a file request from another user as a server. behave. Thereby, data distribution is realized without providing a specific server.
JP-T-2002-522956

  Since a peer-to-peer data distribution system can efficiently distribute data to a large number of users, it is expected to be applied to an inter-business service field called B2B (B2B). However, on the other hand, a mechanism for maintaining high security and ensuring reliable delivery management is necessary.

  However, in a conventional peer-to-peer data distribution system, particularly a data distribution system called pure peer-to-peer, the data distribution control subject is the client side, so the data distribution status and error status on the client side as seen from the data distribution server side There is a problem that it is difficult to grasp the information, and reliable delivery management cannot be performed.

  Also, in a conventional peer-to-peer data distribution system, in order to enable data distribution with a user (computer) connected to a network inside a router having a NAT (Network Address Translation) function and a firewall (Firewall) function, It was necessary to set port forwarding for. However, the router's port forwarding setting may cause a security problem. In a data distribution system as a service in the business field, peer-to-peer between users connected to a local network while maintaining high security. There was a need to solve the data communication.

  The present invention has been made in view of the above-described problems, and enables peer-to-peer data communication between users connected to a local network, and has a large capacity without degrading the security level under reliable management. The object is to realize a system for quickly and efficiently distributing data and streaming data to a large number of users.

  The present invention is a content distribution system comprising a management server that manages distribution of content data, and a plurality of peers that receive distribution of content data from the management server or other clients and distribute the content data to other clients. It is.

  The management server includes: 1) a content management unit that manages content data; 2) client information including client identification information, an IP address, and a port number; distribution schedule information in which content data distributed to the client is set; A management information management unit for managing the supplier information indicating the client in which the content data is stored and the delivery control information in which specific information of each piece of fragment data divided for delivery of the content data is set; and 3) from the client A feed information management unit that receives feed information request and generates and transmits feed information in which content data to be delivered to the client that has made the feed information request is set based on the delivery schedule information; and 4) the feed The content is sent to the client who requested the information. 5) A distribution management unit that returns data distribution control information and supplier information. 5) Receives and holds upload address information including an external IP address and an external port number at upload from the client. The client receives a download start notification of the specified content data, acquires the external IP address of the requesting client from the download start notification and the external port number at the time of download and holds it as address information at the time of download. And a peer-to-peer communication management unit for notifying the client of client information of the requesting client and address information at the time of download.

  The client 1) makes a feed information request to the management server and acquires the feed information, and 2) specifies content data to be distributed based on the feed information, and manages the management information. A distribution information acquisition unit that acquires distribution control information and supplier information of the content from the server, and 3) specifies a client that is a request destination of the content data based on the supplier information, and requests the client A download processing unit that transmits a download start notification of the specified content data to the management server and receives the content data in units of fragment data from the requested client; 4) received based on the distribution control information The integrity of the received fragment data is checked, and if the received fragment data is incomplete, the request destination A received data check unit for requesting retransmission of the fragment data to the client, 5) a received content management unit for storing the received complete fragment data in the content storage unit, and 6) an external IP address and an external port at the time of uploading An inter-peer communication setting unit for notifying the management server of upload address information including a number and receiving client information of the client requesting the content data and download address information from the management server; and 7) the download And an upload processing unit that receives a download request from the requesting client that sent the start notification and transmits the fragment data of the content data based on the distribution control information without connection.

  The present invention operates as follows.

  The management server manages the content data to be distributed by the content management unit. The management information management unit manages client information, distribution schedule information, supplier information, and distribution control information.

  Also, the peer-to-peer communication management unit of the management server receives this upload address information including the external IP address and the external port number at the upload at regular intervals from the client peer-to-peer communication setting unit. Holds the time address information.

  When the feed information acquisition unit of the client requests the feed information to the management server, the feed information management unit of the management server generates feed information in which content data to be delivered to the client is set based on the delivery schedule information And send it to the client.

  The distribution information acquisition unit of the client that has made the feed information request identifies content data that requires distribution based on the feed information acquired from the management server by the feed information acquisition unit, and relates to the distribution of the content data to the management server. Request information. The distribution management unit of the management server returns the distribution control information and supplier information of the content data to the client. Further, the download processing unit of the client specifies the client that is the request destination of the content data based on the supplier information, and transmits a download start notification specifying the client that is the request destination of the content data to the management server.

  The peer-to-peer communication management unit of the management server acquires the external IP address of the requesting client and the external port number at the time of download processing from the download start notification of the requesting client, and retains them as download address information. Further, the client information of the request source client and the download address information are notified to the request destination client.

  The peer-to-peer communication setting unit of the request destination client receives the client information and download address information of the request source client, and when the download processing unit receives the download request, the content data fragment data is sent to the request source client. Is sent connectionlessly. This data transmission is performed by UDP (User Datagram Protocol).

  Then, the download processing unit of the requesting client receives the content data from the requesting client in units of fragment data. Subsequently, the received data check unit checks the integrity of the received fragment data based on the content data distribution control information. If the received fragment data is incomplete, the received data is sent to the requesting client. Request retransmission. On the other hand, if the received fragment data is complete, the received content management unit stores it in the content storage unit.

  Further, when the present invention has the above configuration, the management server includes a content transmission unit that receives a download start notification in which the management server itself is set as a request destination from the client and transmits the requested content data. it can.

  Furthermore, the management information management unit of the management server can manage the distribution schedule information in which the distribution period of the content data is set. In this case, the feed information management unit of the management server generates feed information based only on the distribution schedule information whose request date and time is within the distribution period, and returns it to the client.

  Furthermore, the management information management unit of the management server can manage distribution group information in which a group of clients that receive distribution of the same content data is set. In this case, based on the distribution group information, the distribution management unit of the management server transmits supplier information in which only clients belonging to the same group as the client that has requested confirmation are set as suppliers.

  The present invention is also a management server content distribution program that operates on a management server of the content distribution system and a client content distribution program that operates on a client.

  The program according to the present invention can be stored in an appropriate recording medium such as a computer-readable portable medium memory, a semiconductor memory, and a hard disk, and is provided by being recorded on these recording media or a communication interface. It is provided by transmission and reception using various communication networks.

  According to the present invention, the management server holds distribution schedule information, further supplier information necessary for distribution processing, distribution control information, etc., and notifies the client of feed information generated based on the distribution schedule information for identification. Distributed content data. In addition, the client makes a download request to another client based on the information related to distribution obtained from the management server, and acquires content data by peer-to-peer data communication. Therefore, the management server can control content distribution completely, including distribution schedules, content data to be distributed, and clients that receive distributions, and can also manage peer-to-peer content between clients. Data distribution can also be managed.

  In addition, the management server manages client address information necessary for peer-to-peer data communication, and notifies the client that performs peer-to-peer data communication. Therefore, data communication can be performed between clients connected to the internal network of the router having the NAT function, and the port forwarding setting of the router that is likely to cause a security problem can be eliminated.

  In the present invention, since the upload processing unit of the client transmits content data in units of fragment data, efficient data distribution can be realized. Further, since the upload processing unit transmits the fragment data without connection, the data distribution processing itself can be accelerated.

  In addition, the client's received data check unit checks the integrity of the received fragment data, so the window size of the check process can be set arbitrarily, and the data can be checked at a higher speed than TCP (Transmission Control Protocol). The distribution process itself can be speeded up.

  As described above, the present invention can be applied to a data distribution service in a business field in which security is important, and a large amount of data and streaming data are provided to a large number of users with high security, high speed and efficiency. A system that can be distributed in a distributed manner.

  The best embodiment of the present invention will be described below.

  FIG. 1 is a diagram showing a configuration example of a content distribution system according to the present invention.

  The content distribution system 1 according to the present invention includes a management server 10 and a plurality of clients 20 (20A, 20B,...). Content data (for example, moving image data) managed by the management server 10 is transferred to a predetermined client 20. (20A, 20B).

  The management server 10 and the clients 20 (20A, 20B) are computers installed in the local network, and are connected to the Internet 3 via routers 11 and 21 (21A, 21B).

  One or a plurality of DMS (Digital Media Server) 22 (22A, 22B) is connected to the client 20 (20A, 20B), and further, one or a plurality of DMA (Digital Media Adapter) is connected to the DMS (Digital Media Server) 22. 23 (23A, 23B) are connected.

  The DMS 22 (22A, 22B) and the DMA 23 (23A, 23B) are devices compliant with the Digital Living Network Alliance (DLNA). The client 20 and the DMS 22 can be implemented as a single device.

  In the client A, when the client 20A receives distribution of content data under the management of the management server 10, the content data is transferred to the DMS 22A, and the DMS 22A further transfers to the DMA 23A. A predetermined playback device (not shown) that has acquired the content data from the DMA 23A performs a playback process, so that the user can view the content data.

  FIG. 2 is a diagram illustrating an example of content data distribution in the content distribution system 1.

  In the content distribution system 1 of FIG. 2, the management server (conductor) 10 distributes content data to a client (satellite) 20 that distributes content to other clients as a base. The client (satellite) 20 that has received the distribution of the content data transmits the content data by peer-to-peer to the other client 20 (user). The client 20 distributes content data by peer-to-peer between satellites, between satellites and users, and between users.

  In addition, the management server 10 can set a period during which content can be distributed (distribution period) and permit only distribution requests within the distribution period. Furthermore, a distribution group capable of distributing content data can be set, and management can be performed so that content data is distributed only between clients in the distribution group (clients in a range surrounded by a broken line).

  FIG. 3 is a diagram for explaining distribution processing in units of fragment data of content data in the content distribution system 1.

  In the content distribution system 1, the content data is distributed in units of fragment data divided into a predetermined size (for example, 20 Kbytes). The management server 10 prepares distribution control information indicating content division information, a hash value for checking the integrity of each piece of fragment data, the order of the pieces of fragment data, and requests the feed information prior to distribution of the content data. It transmits to the client 20 which performed. The client 20 checks the received fragment data with the distribution control information. If the fragment data is complete, the client 20 transmits the fragment data to another client (satellite or user) 20.

  For example, the client (satellite) 20A that has received the distribution of “fragment data 1” of the content data from the management server 10 checks the completeness and then sends it to the other clients 20 (satellite 20B, users 20P, 20Q, 20R). Send fragment data 1 ”. On the other hand, the client (satellite) 20B that has received the distribution of the “fragment data 2” of the content data from the management server 10 checks the completeness and then similarly uses the other clients 20 (satellite 20A, users 20P, 20Q, 20R). ) Send “fragment data 2”. As a result, the content data can be efficiently distributed to many clients 20.

  FIG. 4 is a diagram illustrating an internal configuration example of the management server 10.

  The management server 10 includes a content management unit 101, a client management unit 103, a distribution schedule information management unit 104, a distribution group information management unit 105, a supplier information management unit 106, a distribution control information management unit 107, which are configured by software programs and the like. A feed information management unit 110, a distribution management unit 111, an inter-peer communication management unit 112, and a content transmission unit 113 are provided.

  The content management unit 101 is a processing unit that manages content data to be distributed stored in the content storage unit 120 using content management information (content management table).

  FIG. 5 is a diagram illustrating an example of the data structure of the content management table. The content management table stores information such as content ID (identification information), content name, content path, and content hash value for each content data.

  The client management unit 103 is a processing unit that manages the client 20 constituting the content distribution system 1 using client information (client table).

  FIG. 6 is a diagram illustrating an exemplary data structure of the client table. The client table stores information such as a client ID, a client name, an IP address, a port number, an external IP address, and an external port number for each client. The external IP address and external port number are the IP address outside the router 21 to which the client 20 is connected and the port number at the time of upload.

  The client table may further store information such as a MAC address.

  The distribution schedule information management unit 104 is a processing unit that manages distribution schedule information (distribution schedule table).

  FIG. 7 is a diagram illustrating a data structure example of the distribution schedule table. In the distribution schedule table, information such as a content ID, a distribution group ID, a distribution start time, and a distribution end time is stored for each content data. The distribution start time and the distribution end time are a start date and an end date and time of a period during which the management server 10 distributes the content data.

  The distribution group information management unit 105 is a processing unit that manages a distribution group indicating the range of the client 20 to which the same content data is distributed based on the distribution group information.

  FIG. 8 is a diagram illustrating an example of the data structure of the distribution group table and the group configuration table constituting the distribution group information.

  In the distribution group table of FIG. 8A, information such as distribution group ID, distribution group name, initial number of suppliers, and child ratio is stored for each distribution group. The initial number of suppliers is the number of clients (suppliers) that hold and distribute content data at the initial stage in the distribution group.

  The child ratio is a ratio between a client (for example, the satellite in FIG. 3) 20 serving as a supplier and a client (for example, the user in FIG. 3) 20 that receives distribution from the sharer.

  The content distribution system 1 sets the number of clients 20 (initial suppliers) serving as suppliers in the distribution group and the ratio with the clients (children) 20 that can receive distribution of content data from the suppliers (satellite). As a result, it is possible to control the distribution route of the content data.

  For example, when “the number of initial suppliers = 2, the ratio of children = 1”, the number of clients (satellite) of initial suppliers that receive distribution from the management server 10 = 2, and the clients that receive distribution from each satellite 20 (child users) ) Number = 2, the number of clients (grandchild users) receiving distribution from each child user 20 = 2,...

  Further, in the case of “the number of initial suppliers = 2, the child ratio = 2”, the number of clients (satellite) of the initial supplier receiving distribution from the management server 10 is equal to 2 and the clients receiving each distribution from the satellite 20 (child users) ) Number = 4, and the number of clients (grandchild users) receiving distribution from each child user 20 = 8,...

  In the group configuration table of FIG. 8B, information such as a distribution group ID, a client ID (client which is a member), and an initial supplier flag is stored for each distribution group. The initial supplier flag is a flag indicating whether the client is an initial supplier.

  The supplier information management unit 106 is a processing unit that manages the client 20 that has become the content data supplier based on the supplier information (supplier table).

  FIG. 9 is a diagram illustrating an example of the data structure of the supplier table. The supplier table stores information such as client ID and content ID (content data that can be distributed) for each client as a supplier. In the case where the client 20 of the content distribution system 1 has a hierarchical relationship and the client 20 of its upper layer is a supplier, the supplier table includes a hierarchy (hierarchy to which the client belongs), an index within the hierarchy (in the hierarchy) Information such as (identification information) may be stored.

  The distribution control information management unit 107 is a processing unit that manages distribution control information (distribution control file) of content data.

  FIG. 10 is a diagram illustrating an example of the data structure of the distribution control file. The distribution control file stores information such as storage location (URL), content name, content size, fragment data size, hash value of each fragment data, and the like for each content data.

  When the feed information management unit 110 receives a request for feed information from the client 20, the feed information management unit 110 generates, based on the distribution schedule, feed information in which content data to be distributed to the requested client 20 is set and returns the processing. It is.

  FIG. 11 is a diagram illustrating an example data structure of feed information. The feed information includes a client ID, a content ID list (a list of contents held by the client as a distribution target), a port number (port number at the time of upload), for each client that can distribute to the requesting client. Stores information such as the delivery time (latest date of reply of feed information).

  The distribution management unit 111 is a processing unit that, when receiving a content data distribution request from the client 20 that has requested the feed information, returns the content data distribution control information and supplier information. The distribution management unit 111 transmits a distribution control file (FIG. 10). In addition, a list of clients 20 serving as suppliers is generated and transmitted based on the supplier table (FIG. 9).

  In addition, the distribution management unit 111 manages the status of the client 20, the distribution status, and exceptions that have occurred in the client 20.

  FIG. 12 is a diagram illustrating an example of a data structure of a client state table for managing the state of the client 20. The client status table stores information such as the client ID, status status, and confirmation time (latest date and time when the status was confirmed) for each client. The status status is a predetermined status indicating the status of the client. For example, “1 = stopping, 2 = starting, 3 = restarting, 4 = restarting request” is set.

  FIG. 13 is a diagram illustrating a data structure example of a distribution status table for managing the distribution status of the client 20. In the distribution status table, for each client, the client ID, content ID (content data being distributed), distribution status status, number of download completed bytes, number of remaining download bytes, number of uploaded bytes, download start time, update time, etc. Information is stored. The distribution status status is a predetermined status indicating the distribution status (download processing status) of the client 20, for example, “1 = starting, 2 = downloading processing, 3 = completed, 4 = stopping, 5 = retransmission. “Requesting” is set.

  FIG. 14 is a diagram showing an example of the data structure of an exception table that records exception processing notified from the client 20. The exception table stores information such as a client ID, a service ID (service (process) in which an exception has occurred), an occurrence time, an exception ID, and details (specific details of the exception) for each client.

  The peer-to-peer communication management unit 112 receives an external IP address and uploading external port number (uploading address information) from the client 20, writes it in the client table, and requests content data from the client 20 that has made a feed information request. When the destination client receives the specified download start notification, the download start notification notifies the request destination client of the external IP address of the requesting client 20 and the external port number (download address information) during the download process. At the same time, it is a processing unit that notifies the address information of the requesting client 20.

  The peer-to-peer communication management unit 112 manages the setting of peer-to-peer data communication performed by the client 20 using the peer-to-peer communication information table, and returns a response to an acquisition request from the client.

  FIG. 15 is a diagram illustrating an example of the data structure of the peer-to-peer communication information table. The peer-to-peer communication information table includes information such as the client ID of the connection source (own) client, the external IP address, the external port number, and the client ID of the connection destination (partner) client for each client performing peer-to-peer data communication. Is stored.

  The content transmission unit 113 is a processing unit that transmits the requested content data when receiving a download start notification in which the management server 10 is set as a request destination from another client 20.

  FIG. 16 is a diagram illustrating an internal configuration example of the client 20.

  The client 20 includes a feed information acquisition unit 201, a distribution information acquisition unit 202, a download processing unit 203, a received data check unit 204, an inter-peer communication setting unit 205, an upload processing unit 206, and a received content management unit configured by software programs and the like. 207, a content storage unit 210, a client automatic registration unit 221, and an exception notification unit 222.

  The feed information acquisition unit 201 is a processing unit that acquires the feed information requested to the management server 10.

  The distribution information acquisition unit 202 is a processing unit that specifies content data to be distributed based on the feed information, and acquires content data distribution control information and supplier information from the management server 10.

  The download processing unit 203 identifies the client 20 that is the request destination of the content data based on the supplier information, transmits a download start notification specifying the request destination client 20 to the management server 10, and the requested client 20 Is a processing unit that receives content data in units of fragment data.

  The received data check unit 204 checks the integrity of the fragment data received by the download processing unit 203 based on the distribution control information. If the received fragment data is incomplete, the received data check unit 204 sends the fragment data to the requested client 20. Is a processing unit for requesting retransmission of a message.

  The peer-to-peer communication setting unit 205 notifies the management server 10 of upload address information including the external IP address of the client 20 and the external port number at the time of upload, and the client information of the requesting client 20 from the management server 10. And a processing unit that receives the download address information.

  The upload processing unit 206 is a processing unit that receives a download request and transmits fragment data of content data to the requesting client 20 without connection. The upload processing unit 206 performs UDP / IP data packet transmission as connectionless data communication.

  FIG. 17 is a diagram illustrating a structure example of a data packet transmitted by the upload processing unit 206. The upload processing unit 206 generates a UDP packet that includes the content packet in the body portion. The content packet is a fragment of each fragment data of the content data. The fragment data identification information (identifier), the packet identification information (packet ID), and the total number of packets constituting the fragment data (total number of packets) ), (Packet index) indicating the sequence of packets is set. The body part is a fragment data body (data).

  The received content management unit 207 is a processing unit that writes or reads the received complete fragment data to the content storage unit 210.

  The client automatic registration unit 221 is a processing unit that transmits predetermined information to the management server 10 and makes a registration request to become the client 20 of the content distribution system 1.

  The exception notification unit 222 is a processing unit that transmits an exception notification in which an exception that has occurred in the client 20 is recorded to the management server 10.

  18 and 19 are diagrams for explaining the processing flow of the content distribution system 1 and the relationship between the processing units.

  Here, the client 20A is a client that confirms distribution and requests distribution of content data, and the client 20B is a client that holds the content data requested by the client 20A and becomes a supplier.

  Step S1: The feed information acquisition unit 201 of the client 20A polls the management server 10 at regular intervals to request feed information.

  Step S2: Upon receiving the feed information request, the feed information management unit 110 of the management server 10 confirms the delivery schedule information in the management information storage unit 130.

  Step S3: If the delivery schedule information has been changed, the feed information management unit 110 creates and transmits the feed information of the client 20A based on the changed delivery schedule information.

  Step S4: The feed information acquisition unit 201 activates the distribution information acquisition unit 202.

  Step S5: The distribution information acquisition unit 202 specifies the content data D as a request target from the feed information, and requests the management server 10 for distribution control information of the content data D.

  Step S6: The distribution management unit 111 acquires the distribution control file of the content data D from the management information storage unit 130.

  Step S7: The distribution management unit 111 transmits the distribution control file of the content data D to the client 20A.

  Step S8: The distribution information acquisition unit 202 activates the download processing unit 203.

  Step S9: The download processing unit 203 notifies the management server 10 of the download start of the content data D and requests a supplier list of the content data D.

  Step S10: The distribution management unit 111 refers to the supplier table in the management information storage unit 130, and transmits a supplier list of content data D (a list of clients 20 serving as suppliers) to the client 20A. Here, the client 20A specifies the client 20B as a request destination of the content data D from the acquired supplier information of the content data D.

  The processes in steps S11 to S20 below are processes for performing peer-to-peer data communication between the clients 20A and 20B. FIG. 20 is a diagram illustrating the relationship between the management server 10 and the clients 20A and 20B in the processing of steps S11 to S20 in FIG.

  Step S11: The peer-to-peer communication setting unit 205 of the client 20B notifies the upload server (external IP address and external port number during upload processing) to the management server 10 at regular intervals. For example, notification is performed by transmitting a data packet from a port used by the upload processing unit 206.

  Step S12: The peer-to-peer communication management unit 112 of the management server 10 notifies the client management unit 101 of the upload address information of the client 20B. The client management unit 101 updates the client table in the management information storage unit 130.

  Step S13: The download processing unit 203 of the client 20A requests the management server 10 to start download specifying the request destination.

  Step S14: The peer-to-peer communication management unit 112 extracts the download-time address information (external IP address and external port number at the time of download) from the download start request, and uses the download-time address information and the requested client ID (client 20B). Write to peer communication information table.

  Step S15: The download processing unit 203 of the client 20A transmits a packet to the external port at the time of uploading to the client 20B. As a result, a request for peer-to-peer data communication with the client 20B is made.

  Step S16: The peer-to-peer communication setting unit 205 of the client 20B polls the management server 10 at regular intervals and requests peer-to-peer communication information.

  Step S17: The inter-peer communication management unit 112 of the management server 10 acquires an inter-peer communication information table.

  Step S18: The peer-to-peer communication management unit 112 returns the acquired information in the peer-to-peer communication information table to the client 20B.

  Step S19: The peer-to-peer communication setting unit 205 of the client 20B activates the upload processing unit 206.

  Step S20: The upload processing unit 206 of the client 20B transmits a packet to the external port of the download processing unit 203 of the client 20A. As a result, the client 20A can receive the packet of the client 20B.

  Step S21: The download processing unit 203 of the client 20A requests the upload processing unit 206 of the client 20B to download the content data D.

  Step S22: The upload processing unit 206 of the client 20B transmits the fragment data of the content data D to the download processing unit 203 of the client 20A.

  Step S23: The received data check unit 204 of the client 20A checks the integrity of the received fragment data based on the distribution control information (fragment data hash value). If the fragment data is not complete, the download processing unit 203 is notified. The download processing unit 203 requests retransmission of incomplete fragment data.

  Further, the received content management unit 207 stores the fragment data of the content data D in the content storage unit 210.

  Thereby, the client 20A can receive the distribution of the content data D from the client 20B under the distribution management of the management server 10.

  Thereafter, when the client 20A receives a download request for the content data D from another client 20C, the download processing unit 206 transmits the content data D to the requesting client 20C, as with the client 20B. .

  The distribution management unit 111 of the management server 10 acquires the client status and distribution status from the clients 20A and 20B at a predetermined interval or trigger, and updates the client status table and distribution status table. As a result, the state and distribution status of the client 20 can always be grasped.

  As mentioned above, although this invention was demonstrated by the embodiment, it cannot be overemphasized that a various deformation | transformation is possible for this invention in the range of the main point. For example, in the embodiment of the present invention, the management server 10 is described as including the content storage unit 120 and holding the content data. However, the content distribution system 1 may be configured such that processing means for holding and managing content data to be distributed is provided outside the management server 10 so as to cooperate with each other.

It is a figure which shows the structural example of the content delivery system concerning this invention. It is a figure which shows the example of delivery of the content data of a content delivery system. It is a figure for demonstrating the delivery process by the fragment data unit of content data. It is a figure which shows the internal structural example of a management server. It is a figure which shows the example of a data structure of a content management table. It is a figure which shows the data structure example of a client table. It is a figure which shows the example of a data structure of a delivery schedule table. It is a figure which shows the data structure example of the distribution group table which comprises distribution group information, and a distribution group structure table. It is a figure which shows the data structure example of a supplier table. It is a figure which shows the data structure example of a delivery control file. It is a figure which shows the data structure example of feed information. It is a figure which shows the data structure example of a client status table. It is a figure which shows the example of a data structure of a delivery status table. It is a figure which shows the data structure example of an exception table. It is a figure which shows the example of a data structure of the communication information table between peers. It is a figure which shows the internal structural example of a client. It is a figure which shows the structural example of the data packet transmitted by the upload process part. It is FIG. (1) for demonstrating the flow of a process of a content delivery system, and the relationship of each process part. It is FIG. (2) for demonstrating the flow of a process of a content delivery system, and the relationship of each process part. It is a figure which shows the relationship between the management server and client in the process of step S11-S20 of FIG.

Explanation of symbols

1 Content Distribution System 3 Internet 10 Management Server 11, 21 Router 20 Client 22 DMS
23 DMA
DESCRIPTION OF SYMBOLS 101 Content management part 103 Client management part 104 Distribution schedule information management part 105 Distribution group information management part 106 Supplier information management part 107 Distribution control information management part 110 Feed information management part 111 Distribution management part 112 Peer communication management part 113 Content transmission Unit 120 content storage unit 130 management information storage unit 201 feed information acquisition unit 202 distribution information acquisition unit 203 download processing unit 204 received data check unit 205 peer communication setting unit 206 upload processing unit 207 received content management unit 210 content storage unit 221 client Automatic registration unit 222 Exception notification unit

Claims (6)

A content distribution system configured by a management server that manages distribution of content data, and a plurality of peers that receive distribution of content data from the management server or other clients and distribute content data to other clients,
The management server
A content management unit for managing content data;
Distribution of client information including client identification information, IP address and port number, distribution schedule information in which content data distributed to the client is set, supplier information indicating the client storing the content data, and distribution of content data A management information management unit for managing distribution control information in which specific information of each piece of fragment data divided for use is set;
A feed information management unit that receives a feed information request from a client, generates feed information in which content data to be delivered to the client that has made the feed information request based on the delivery schedule information is set, and transmits the feed information;
A delivery management unit that returns delivery control information and supplier information of the content data to the client that has made the feed information request;
The upload side address information including the external IP address and the external port number at the time of upload is received and held from the client, the requested client receives a download start notification of the specified content data, and the request source receives the download start notification. Peer-to-peer communication that acquires the external IP address of the client and the external port number at the time of download, holds it as download side address information, and notifies the request destination client of the client information and download side address information of the request source client A management department,
The client
A feed information acquisition unit that makes a feed information request to the management server and acquires the feed information;
A distribution information acquisition unit that specifies content data to be distributed based on the feed information and acquires distribution control information and supplier information of the content from the management server;
Based on the supplier information, a client as a request destination of the content data is specified, and a download start notification of the content data specifying the request destination client is transmitted to the management server. A download processing unit for receiving the content data in fragment data units;
A received data check unit that checks the integrity of the received fragment data based on the distribution control information and requests the requested client to retransmit the fragment data if the received fragment data is incomplete; ,
A received content management unit for storing the received complete fragment data in a content storage unit;
Between the peers that notify the management server of upload side address information including the external IP address and the external port number at the time of upload, and receive client information and download side address information of the client requesting the content data from the management server A communication setting section;
A content distribution system comprising: an upload processing unit that receives a download request from a requesting client that has made the download start notification and transmits the fragment data of the content data based on the distribution control information without connection. A management information management unit of the management server manages the distribution schedule information in which a distribution period of content data is set;
2. The content according to claim 1, wherein the feed information management unit generates the feed information based only on distribution schedule information in which a date and time of the feed information request is within a distribution period, and sends the feed information back to the client. Distribution system. The management information management unit of the management server manages distribution group information in which a group of clients that receive distribution of the same content data is set,
The delivery management unit transmits supplier information set as a supplier only to a client belonging to the same group as the client that has requested the feed information based on the delivery group information. The content distribution system according to claim 1 or 2. The management information management unit of the management server manages distribution route information in which a relationship between the number of clients to which the management server supplies content data and the number of other clients that receive the distribution of the content data is set.
2. The delivery management unit, based on the delivery route information, transmits supplier information in which only a client specified as a supplier to the client that has made the feed information request is set. The content distribution system according to any one of claims 3 to 4. The management server of a content distribution system comprising a management server that manages the distribution of content data and a plurality of clients that receive the distribution of content data from the management server or other clients and distribute the content data to other clients A program that runs on
A content management unit for managing content data;
Distribution of client information including client identification information, IP address and port number, distribution schedule information in which content data distributed to the client is set, supplier information indicating the client storing the content data, and distribution of content data A management information management unit for managing distribution control information in which specific information of each piece of fragment data divided for use is set;
A feed information management unit that receives a feed information request from a client, generates feed information in which content data to be delivered to the client that has made the feed information request based on the delivery schedule information is set, and transmits the feed information;
A delivery management unit that returns delivery control information and supplier information of the content data to the client that has made the feed information request;
The upload side address information including the external IP address and the external port number at the time of upload is received and held from the client, the requested client receives a download start notification of the specified content data, and the request source receives the download start notification. Peer-to-peer communication that acquires the external IP address of the client and the external port number at the time of download, holds it as download side address information, and notifies the request destination client of the client information and download side address information of the request source client As the management server comprising a management unit,
A management server content distribution program for causing a computer to function. The client of the content distribution system configured by a management server that manages the distribution of content data and a plurality of clients that receive the distribution of content data from the management server or other clients and distribute the content data to other clients A program that runs,
A feed information acquisition unit that makes a feed information request to the management server and acquires the feed information;
A distribution information acquisition unit that specifies content data to be distributed based on the feed information and acquires distribution control information and supplier information of the content from the management server;
Based on the supplier information, a client as a request destination of the content data is specified, and a download start notification of the content data specifying the request destination client is transmitted to the management server. A download processing unit for receiving the content data in fragment data units;
A received data check unit that checks the integrity of the received fragment data based on the distribution control information and requests the requested client to retransmit the fragment data if the received fragment data is incomplete; ,
A received content management unit for storing the received complete fragment data in a content storage unit;
Between the peers that notify the management server of upload side address information including the external IP address and the external port number at the time of upload, and receive client information and download side address information of the client requesting the content data from the management server A communication setting section;
An upload processing unit that receives a download request from the requesting client that has made the download start notification and transmits the content data fragment data based on the distribution control information without connection, as the client,
A client content distribution program for causing a computer to function.

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