JP5998987B2 - Communication system, information processing apparatus, and program - Google Patents

Description

  The present invention relates to a technical field of a communication system using an overlay network.

  Conventionally, a peer-to-peer communication system is known. In a peer-to-peer communication system, a plurality of contents are distributed and stored in a plurality of node devices in an overlay network composed of a plurality of node devices. Each node device constituting the overlay network can acquire content from other node devices via the overlay network. On the other hand, a terminal device that does not constitute an overlay network can acquire content via the node device by connecting to the node device that constitutes the overlay network.

  Among the contents that are distributed and stored, there is composite content that is generated using a plurality of material data. A plurality of material data used for generating the composite content is distributed and stored in a plurality of node devices in the overlay network. With regard to the technology of such a peer-to-peer communication system, Patent Document 1 discloses a technology in which material data is disclosed to a peer-to-peer network, and an arbitrary peer configuring the peer-to-peer network generates a program content by combining a plurality of material data. Is disclosed.

JP 2004-80307 A

  By the way, among the node devices constituting the overlay network or the terminal devices connected to the node devices, there are devices that do not have the ability to generate composite content using a plurality of material data. For this reason, a device that does not have the ability to generate composite content needs to acquire composite content corresponding to the type of the device from another device that stores the composite content.

  However, when it is difficult to use another device that stores composite content due to access concentration or the like, a device that does not have the ability to generate composite content cannot acquire composite content corresponding to the type of the device. There is a problem.

  The present invention has been made in view of the above points, and is a communication system that can quickly provide composite content corresponding to the type of device to a device that does not have the ability to generate composite content. It is an object to provide an information processing device and a program.

  In order to solve the above-described problem, an invention according to claim 1 is an information processing apparatus capable of communicating via an overlay network including a plurality of information processing apparatuses connected to a network, wherein the overlay network is Identification information of composite content generated using a plurality of material data that can be acquired via the first location information indicating the location of the first information processing apparatus that stores the composite content, and the composite content The first content information indicating the type of the information processing device to be stored is associated with the first storage means, the composite content identification information, and the composite material can be generated using the plurality of material data Second storage means for storing the second location information indicating the location of the second information processing apparatus in association with the third information processing apparatus as a transmission source The identification information of the composite content transmitted via the overlay network, the third location information indicating the location of the third information processing device that reproduces the composite content, and the type of the third information processing device Receiving means for receiving the second type information shown, the second type information received by the receiving means, and the identification information of the composite content received by the receiving means. Whether or not the first information processing apparatus that stores the composite content corresponding to the type of the third information processing apparatus is usable based on the first type information stored in the storage unit And when the first information processing apparatus determines that the first information processing apparatus is not usable by the first determination means. Determining means for determining the second information processing apparatus corresponding to the second location information stored in the second storage means in association with the identification information of the content as the information processing apparatus for generating the composite content; It is characterized by providing.

  According to a second aspect of the present invention, in the information processing apparatus according to the first aspect, the second storage unit stores the material stored in each of the plurality of second information processing apparatuses capable of generating the composite content. Data identification information is stored in association with the second location information, and the information processing apparatus stores the second information associated with the composite content identification information received by the receiving unit. The apparatus further comprises second determination means for determining whether a plurality of location information is stored in the second storage means, and a plurality of the second location information is stored in the second storage means by the second determination means. If it is determined that the plurality of material data are used for generating the composite content identified by the composite content identification information received by the reception unit. Among the information, the second information processing device corresponding to the second location information having a higher number of pieces of identification information of the material data associated with the second location information is used as the composite content. It is determined as an information processing device to be generated.

  According to a third aspect of the present invention, in the information processing apparatus according to the first or second aspect, the information processing apparatus includes the identification information of the composite content received by the receiving unit, the third information processing apparatus The information processing apparatus further includes a transmission unit that transmits the third location information and the second type information to the second information processing device when the information processing device is determined by the determining unit.

  According to a fourth aspect of the present invention, there is provided a computer capable of communicating via an overlay network composed of a plurality of information processing apparatuses connected to a network, wherein a plurality of material data that can be acquired via the overlay network is obtained. Identification information of the composite content generated by using the first location information indicating the location of the first information processing device storing the composite content, and a first type indicating the type of the information processing device to which the composite content corresponds. The first storage means for storing the type information in association with each other, the identification information of the composite content, and the location of the second information processing apparatus capable of generating the composite content using the plurality of material data A second information processing device that stores second location information in association with the third information processing device as a transmission source. The identification information of the composite content transmitted via the overlay network, the third location information indicating the location of the third information processing device that reproduces the composite content, and the type of the third information processing device A reception step of receiving the second type information shown, the second type information received by the reception step, and the identification information of the composite content received by the reception step. Whether or not the first information processing apparatus that stores the composite content corresponding to the type of the third information processing apparatus is usable based on the first type information stored in the storage unit If the first determination step determines that the first information processing apparatus is not usable by the first determination step, the reception step The second information processing apparatus corresponding to the second location information stored in the second storage means in association with the received identification information of the composite content is used as an information processing apparatus for generating the composite content. And a determining step for determining.

  The invention according to claim 5 is a communication system including an information processing apparatus capable of communicating via an overlay network composed of a plurality of information processing apparatuses connected to a network, and capable of communicating via the overlay network. The first information processing apparatus includes identification information of composite content generated using a plurality of material data that can be acquired via the overlay network, and a first information processing apparatus storing the first information processing apparatus that stores the composite content. First storage means for associating and storing the location information and first type information indicating the type of information processing apparatus to which the composite content corresponds, identification information of the composite content, and the plurality of material data And the second location information indicating the location of the second information processing apparatus capable of generating the composite content using Second storage means for storing, identification information of the composite content transmitted via the overlay network with the third information processing device as a transmission source, and location of the third information processing device for reproducing the composite content Receiving means for receiving third location information indicating the second type information indicating the type of the third information processing apparatus, the second type information received by the receiving means, and the receiving means The composite content corresponding to the type of the third information processing device based on the first type information stored in the first storage means in association with the identification information of the composite content received by A first determination unit that determines whether or not the first information processing apparatus that stores the information is usable, and the first information processing apparatus is not usable by the first determination unit. The second information processing apparatus corresponding to the second location information stored in the second storage means in association with the identification information of the composite content received by the receiving means. Determining means for determining as the information processing device for generating the composite content, the identification information of the composite content from the information processing device, the third location information of the third information processing device, and the second information The second information processing apparatus that receives the type information, based on the generation unit that generates the composite content identified by the received identification information of the composite content, and the received second type information, Third determination means for determining whether or not the composite content generated by the generation means is to be distributed to the third information processing apparatus by streaming distribution; Distribution means for delivering the composite content to the third information processing apparatus according to the determination by the third determination means.

  According to the first, third, and fourth aspects of the present invention, it is possible to quickly provide composite content corresponding to the type of device to a device that does not have the ability to generate composite content.

  According to the second aspect of the present invention, it is possible to cause the second information processing apparatus capable of generating the composite content to quickly generate the composite content to be requested.

  According to the invention described in claim 5, even when the cache of the composite content is restricted in the third information processing apparatus, the composite content can be quickly distributed.

It is a figure showing an example of outline composition of communications system S of this embodiment. (A) is a figure which shows an example of the registration content of a synthetic content holder list. (B) is a figure which shows an example of the registration content of a content creator list. (C) is a block diagram illustrating a schematic configuration example of the commander Co. (D) is a block diagram illustrating a schematic configuration example of a node Nk. It is a flowchart which shows the main process in the control part 11 of commander Co. (A) is a flowchart which shows the detail of the delivery process of step S1 shown in FIG. (B) is a flowchart showing details of the content type determination processing in step S12 shown in (A). It is a flowchart which shows the detail of the publishing process of step S2 shown in FIG. It is a flowchart which shows the message reception process in the control part 21 of a root node. (A) is a flowchart which shows the detail of the content holder determination process of step S63 shown in FIG. FIG. 6B is a flowchart showing details of the content creator determination process in step S65 shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below is an embodiment when the present invention is applied to a communication system using an overlay network.

[1. Overview of communication system configuration and operation]
First, the configuration and operation outline of the communication system of the present embodiment will be described with reference to FIG. FIG. 1 is a diagram illustrating a schematic configuration example of a communication system S of the present embodiment. As shown in FIG. 1, the communication system S of this embodiment includes an edge server ESn (n: 1 to 7), a mobile terminal Tm (m: 1 to 3), a commander Co (o: 1 to 10), and a set. A top box STBp (p: 1 to 3) is included. Any terminal other than the portable terminal that can be connected to the network may be used. For example, a general computer or tablet PC may be used in addition to the mobile terminal. The edge server ESn, the portable terminal Tm, the commander Co, and the set top box STBp are examples of the information processing apparatus. As described above, various types of information processing apparatuses exist in the communication system S. Such a type of information processing apparatus is referred to as “apparatus type”.

  The edge server ESn and the mobile terminal Tm are connected to the backbone network NW. The backbone network NW includes, for example, the Internet, a mobile communication network, and a gateway. The commander Co and the set top box STBp are connected to each base network NLn. The base network NLn is composed of, for example, a LAN (Local Area Network). The base network NLn is connected to the backbone network NW via each edge server ESn. Also, location information indicating the location in the backbone network NW or the base network NLn is assigned to each of the edge server ESn, the portable terminal Tm, the commander Co, and the set top box STBp. The location information is composed of, for example, an IP address and a port number. The location information can also be used as a device ID that can uniquely identify the edge server ESn, the portable terminal Tm, the commander Co, and the set top box STBp.

  In the example of FIG. 1, in the communication system S, the overlay network ON is configured by participation of the edge server ESn and the mobile terminal Tm. That is, the edge server ESn and the mobile terminal Tm are examples of information processing apparatuses that constitute the overlay network ON. An information processing apparatus constituting the overlay network ON is referred to as a node Nk (k: 1 to 10). The overlay network ON is a logical network that forms a virtual link. The overlay network ON is realized by a specific algorithm, for example, an algorithm using a distributed hash table. The distributed hash table is referred to as “DHT (Distributed Hash Table)”. The node Nk stores a routing table using DHT. In the routing table using DHT, a plurality of pairs of node IDs and location information of nodes Nk that are candidates for transfer destinations of various messages are registered. The node ID is unique identification information that identifies the node Nk among all the nodes Nk participating in the overlay network ON. Also, joining the overlay network ON means operating in a state in which communication with other nodes Nk is possible via the overlay network ON based on a routing table using DHT. Note that a routing table using DHT is known in Japanese Patent Application Laid-Open No. 2006-197400 and the like, and thus detailed description thereof is omitted.

  The edge server ESn has a function of a router that relays IP packets between the backbone network NW and the base network NLn. Thereby, the edge server ESn can relay various data exchanges between the commanders Co or between the commanders Co and the set-top boxes STBp, for example. In the example of FIG. 1, the commander Co and the set top box STBp do not participate in the overlay network ON. However, either the commander Co or the set top box STBp may be configured to participate in the overlay network ON. Further, the mobile terminal Tm may include an information processing apparatus that does not participate in the overlay network ON as the node Nk.

  The commander Co is a performance device that reproduces music based on a user's music selection operation. The commander Co is installed in a karaoke store, for example. For example, the synthesized content of the music is stored in the storage unit of the commander Co. The music composition content is content used for music reproduction. The music includes karaoke music. This composite content is an example of composite content generated using a plurality of material data that can be acquired via the overlay network ON. A content ID is assigned to the composite content. The content ID is unique identification information for identifying the composite content from all the content that can be acquired via the overlay network ON. A plurality of composite contents are distributed and stored in a plurality of karaoke Cos. For example, the composite content with the title “AAA” is stored in the commander C1, and the composite content with the title “BBB” is stored in the commander C3. The material data is one component used for generating the composite content. The material data is hereinafter referred to as “part content”. Similar to the composite content, the above-described content ID is also given to the component content. The component content is distributed and stored in a plurality of karaoke Cos, like the composite content. Examples of musical piece content include performance data, background video data, and telop data. The performance data is data for playing music. The performance data includes sound source types such as MIDI (Musical Instrument Digital Interface) data, PCM (Pulse Code Modulation) data, and MP3 (MPEG Audio Layer-3) data. The MIDI data is data composed of control information indicating, for example, a track, a channel, a pitch, a sound length, a volume, and the like. The PCM data is raw sound data in which the sound waveform of the music is not compressed. The MP3 data is data in a compressed format in which the waveform of the music sound is compressed. The background video data is data for displaying a background video (moving image). The background video data includes video types such as normal video data and personal video data. The normal video data is, for example, data indicating a video of a landscape or the like unrelated to the singer himself. The principal video data is, for example, data indicating a video such as a promotion video of the singer himself. The telop data is data for displaying the lyrics telop of the music. The lyrics telop is displayed superimposed on the background video. The telop data includes character data constituting the lyrics telop, data indicating the display timing of the lyrics telop, and the color painting timing.

  The commander Co generates composite content using, for example, a plurality of component contents. Further, the commander Co delivers composite content corresponding to the requesting device type via the edge server ESn in response to a request from the portable terminal Tm or the set top box STBp. Here, the request source refers to the mobile terminal Tm or the set top box STBp that has requested composite content. Even if the synthesized content is the same music, it is divided into a plurality of types according to the device type. Such a type is called a “content type”. The content type indicates the device type to which the composite content corresponds. The content type is an example of first type information. For example, composite content is divided into content types for set-top boxes and mobile terminals. Furthermore, the composite content is divided into, for example, for the portable terminal T1, for the portable terminal T2, and for the portable terminal T3 according to the device type of the portable terminal. The reason why the content types are divided in this way is because, for example, the processing capability differs for each device type. The set content for the set top box is generated by, for example, synthesizing the personal video data, PCM data, and telop data. The composite content for the mobile terminal T1 is generated by, for example, combining normal video data, PCM data, and telop data. The composite content for the portable terminal T2 is generated by, for example, combining normal video data, MIDI data, and telop data. Further, the composite content for the mobile terminal T3 is generated by, for example, combining MIDI data and telop data. Background video data is not used for the composite content for the portable terminal T3. The portable terminal Tm and the set top box STBp reproduce music based on the composite content distributed from the commander Co.

  In the present embodiment, unlike the commander Co, the mobile terminal Tm and the set top box STBp do not generate composite content. Therefore, the mobile terminal Tm and the set top box STBp cannot distribute the composite content. In addition, the mobile terminal Tm and the set top box STBp include an information processing apparatus in which the cache of the composite content distributed from the commander Co is restricted. Such an information processing apparatus does not store the composite content distributed from the commander Co in the storage unit.

  The location of the commander Co that stores the composite content is managed by one of the nodes Nk constituting the overlay network ON. The commander Co that stores the composite content is referred to as a “content holder for the composite content”. The content holder for composite content is an example of a first information processing apparatus. Further, the node Nk that manages the location of the content holder of the composite content is hereinafter referred to as “composite content root node”. The root node of the composite content is determined to be, for example, the node Nk to which the node ID closest to the content ID of the composite content is assigned. The node ID closest to the content ID of the composite content is, for example, the node ID with the highest number of upper digits that match the ID. The root node of the composite content stores a composite content holder list for managing the location of the content holder of the composite content. The composite content holder list is associated with the content ID of the composite content, the location information of the content holder of the composite content, the content type of the composite content, the time required to generate the composite content, the update date and time, the registration date and time of the content holder, and the like. be registered. Here, the time required for generating the composite content is a time required for the content holder to generate the composite content. The update date and time is the date and time when a record including the content ID of the composite content is newly registered or updated and registered in the composite content holder list. The registration date and time of the content holder (hereinafter referred to as “holder registration date and time”) is the date and time when the content holder was registered in the composite content holder list. Furthermore, the root node of the composite content manages the location of the commander Co that can generate the composite content. The commander Co that can generate composite content is referred to as a “content creator”. The content creator is an example of a second information processing apparatus. The root node of the composite content stores a content creator list for managing the location of the content creator. In the content creator list, the content ID of the composite content, the location information of the content creator, the content ID of the component content stored by the content creator, the expiration date of the content creator, and the like are registered in association with each other. Note that the content creator information whose expiration date has passed is deleted from the content creator list. The mobile terminal Tm configuring the overlay network ON may be configured not to manage the location of the content holder and content creator of the composite content. This is because these information processing apparatuses are inferior in processing capability to the edge server ESn.

  FIG. 2A is a diagram illustrating an example of registered content in the composite content holder list. In the composite content holder list shown in FIG. 2A, the location information of the commanders C1 and C3 is registered as content holders storing the composite content “AAA”. Here, the flow until the location information of the commander C1 is registered will be described. When the commander C1 generates and stores the composite content “AAA”, the commander C1 transmits a first publish message to the edge server ES1. The first publish message is a publish message for the composite content holder list. In other words, the first publish message is a message for notifying the root node that the composite content is stored. The first publish message includes the content ID of the composite content “AAA”, the location information of the commander C1, the content type of the composite content “AAA”, and the time required to generate the composite content “AAA”. The edge server ES1 functioning as the node N1 receives the first publish message. The edge server ES1 transmits the received first publish message to the root node of the composite content via the overlay network ON. Here, the transmission of the first publish message is performed by routing using DHT with the content ID of the composite content as a key. Note that routing using DHT is well known in, for example, Japanese Patent Application Laid-Open No. 2007-053662, and detailed description thereof is omitted. The root node of the composite content receives the first publish message. The root node of the composite content acquires the content ID of the composite content, the location information of the commander C1, the content type of the composite content, and the generation time required from the received first publish message. The root node of the composite content registers the acquired content ID of the composite content, the location information of the commander C1, the content type of the composite content, the generation required time, and the like in association with each other in the composite content holder list. Thus, the commander C1 becomes a content holder for storing the composite content “AAA”. The location information of the edge server ES1 to which the commander C1 is connected may be registered in the composite content holder list. In this case, the location information of the edge server ES1 is included in the first publish message. In the composite content holder list, the content ID of the component content used for generating the composite content may be registered in association with the content ID of the composite content.

  FIG. 2B is a diagram illustrating an example of registration contents of the content creator list. In the content creator list shown in FIG. 2B, the location information of the commander C2 and the commander C4 is registered as a content creator capable of generating the composite content “AAA”. Here, the flow until the location information of the commander C4 is registered will be described. The commander C4 transmits a second publish message to the edge server ES3 when there is room for generating the composite content. Details of the process for determining whether or not there is room to generate composite content will be described later. The second publish message is a publish message for the content creator list. In other words, the second publish message is a message for notifying the root node that composite content can be generated. The second publish message includes the content ID of the composite content “AAA”, the location information of the commander C4, and the content ID of the component content stored by the commander C4. This component content is material data used for generating the composite content “AAA”. The edge server ES3 functioning as the node N4 receives the second publish message. The edge server ES3 transmits the received second publish message to the root node of the composite content via the overlay network ON. Here, the transmission of the second publish message is performed by routing using DHT with the content ID of the composite content as a key. The root node of the composite content receives the second publish message. The root node of the composite content acquires the content ID of the composite content, the location information of the commander C4, and the content ID of the component content from the received second publish message. The root node of the composite content registers the acquired content ID of the composite content, the location information of the commander C4, the content ID of the component content, and the like in association with each other in the content creator list. Thus, the commander C4 becomes a content creator capable of generating the composite content “AAA”. The location information of the edge server ES3 to which the commander C4 is connected may be registered in the content creator list. In this case, the location information of the edge server ES3 is included in the second publish message.

  Then, for example, the set top box STB1 may play a song selected by the user, for example. In this case, for example, the set top box STB1 transmits to the edge server ES2 a request message indicating a request for composite content used for music reproduction. The set top box STB1 that is the request source of the composite content is an example of a third information processing apparatus. The request message includes the content ID of the composite content to be requested, the location information of the set top box STB1, and the device type information indicating the device type of the set top box STB1. The device type information is an example of second type information. The edge server ES2 functioning as the node N2 receives the request message. The edge server ES2 transmits the received request message to the root node of the composite content via the overlay network ON. Here, the request message is transmitted by routing using DHT using the content ID of the composite content as a key. For example, the portable terminal T1 configured by the overlay network ON may play music. In this case, the mobile terminal T1 functioning as the node N3 transmits a request message to the root node of the composite content via the overlay network ON without passing through the edge server ESn. The portable terminal T1 in this case is an example of a third information processing apparatus.

  The root node of the composite content receives a request message transmitted via the overlay network ON with the set top box STB1 as a transmission source, for example. The root node of the composite content acquires the content ID of the composite content, the location information of the set top box STB1, and the device type information indicating the device type of the set top box STB1 from the received request message. Based on the acquired device type information and the content type associated with the acquired content ID and registered in the combined content holder list, the root node of the combined content is combined with the device type of the set top box STB1. It is determined whether or not a content holder for storing content is available. Here, the composite content corresponding to the device type of the set top box STB1 is composite content whose content type is for the set top box. Details of the process for determining whether or not the content holder of the composite content can be used will be described later. If the root node of the composite content determines that the content holder of the composite content is usable, the root node of the composite content transmits a response message to the set top box STB1. This response message indicates a response to the composite content request. The response message includes the location information of the content holder that has been determined to be usable. Thereby, the set top box STB1 accesses the content holder of the composite content. The set top box STB1 transmits a request message indicating a request for the composite content to the content holder of the composite content. This request message includes the content ID of the composite content to be requested and device type information indicating the device type of the set top box STB1. Thereby, the set top box STB1 receives the composite content distributed from the content holder of the composite content and reproduces the music. The composite content distributed here is composite content corresponding to the device type of the set top box STB1. A content holder that distributes composite content is also referred to as a distribution device. On the other hand, when it is determined that the content holder of the composite content is not usable, the root node of the composite content determines the content creator corresponding to the location information associated with the acquired content ID and registered in the content creator list. . As a result, the content creator that generates the composite content is determined. When the content creator is determined, the root node of the composite content accesses the content creator based on the location information of the determined content creator. The root node of the composite content transfers the request message to the accessed content creator. This request message may include the content ID of the component content used for generating the composite content.

  Then, the content creator receives a request message transmitted from the root node of the composite content via the overlay network ON. The content creator acquires the content ID of the composite content, the location information of the set top box STB1, and the device type information indicating the device type of the set top box STB1 from the request message. The content creator generates composite content identified by the acquired content ID using the component content. The composite content generated here is composite content corresponding to the device type indicated by the acquired device type information. Further, the content ID of the component content used for generating the composite content is acquired from, for example, a request message. Alternatively, the content ID of the component content used for generating the composite content may be stored in advance in the content creator, for example. The content creator accesses the set top box STB1 based on the acquired location information of the set top box STB1. The content creator distributes the generated composite content to the accessed set top box STB1. A content creator that distributes composite content is also referred to as a distribution device. Here, the content creator may be configured to determine whether to deliver the composite content to the set-top box STB1 by streaming delivery based on the acquired device type information. For example, the device type indicated by the acquired device type information may be a device type for which caching is restricted. In this case, the content creator determines to distribute the composite content to the set top box STB1 by streaming distribution. The device type for which the composite content cache is restricted is, for example, stored in advance in the content creator. Then, the content creator distributes the composite content to the set top box STB1 according to the determination as to whether or not to perform streaming distribution. Thereby, the set top box STB1 receives the composite content distributed from the content holder of the composite content and reproduces the music. Note that determining whether or not to perform streaming distribution is the same as in the case of a content holder for composite content.

  Note that the content creator may not store all or part of the component content used to generate the composite content. In this case, the content creator can acquire unstored component contents from, for example, another commander Co via the overlay network ON. The location of the commander Co that stores the component content is managed by one of the nodes Nk constituting the overlay network ON. The commander Co that stores the component content is referred to as a “component content content holder”. Further, the node Nk that manages the location of the content holder of the part content is hereinafter referred to as “part content root node”. For example, the root node of the component content is determined to be the node Nk to which the node ID closest to the content ID of the component content is assigned. The node ID closest to the content ID of the component content is, for example, a node ID with the highest number of upper digits that match. The root node of the part content stores a part content holder list for managing the location of the content holder of the part content. In the component content holder list, the content ID of the component content, the location information of the content holder of the component content, and the like are registered in association with each other. When the content creator has not saved the component content, the content creator transmits a request message indicating a request for the component content to the edge server ESn to which the content creator is connected. This request message includes the content ID of the requested component content and the location information of the content creator. Upon receiving the request message, the edge server ESn transmits the received request message to the root node of the component content via the overlay network ON. The flow of request message transmission is the same as in the case of composite content. As a result, the content creator acquires component contents that have not been saved. A content holder that distributes component content is also referred to as a distribution device. The mobile terminal Tm configuring the overlay network ON may be configured not to manage the location of the content holder of the component content.

  Further, the commander Co that stores the component content transmits a third publish message to the edge server ESn to which the commander Co is connected. The third publish message is a publish message for the part content holder list. In other words, the third publish message is a message for notifying the root node that the part content is stored. The third publish message includes the content ID of the component content and the location information of the commander Co that stores the component content. When receiving the third publish message, the edge server ESn transmits the received third publish message to the root node of the component content via the overlay network ON. Here, the transmission of the third publish message is performed by routing using DHT with the content ID of the component content as a key. Upon receiving the third publish message, the root node of the component content acquires the content ID of the component content and the location information of the commander Co from the received third publish message. The root node of the component content registers the acquired content ID of the component content and the location information of the commander Co in association with each other in the component content holder list.

  In the example described above, the root node of the composite content is configured to access the content creator based on the location information of the determined content creator when the content creator is determined. However, the root node of the composite content may be configured to return a response message to, for example, the set top box STB1 that is the transmission source of the request message when the content creator is determined. This response message indicates a response to the composite content request. The response message includes, for example, the content ID of the composite content and the location information of the determined content creator. For example, when receiving the response message, the set top box STB1 accesses the content creator based on the location information of the content creator. For example, the set top box STB1 transmits a request message to the accessed content creator. This request message includes, for example, the content ID of the composite content, the location information of the set top box STB1, and the device type information indicating the device type of the set top box STB1. When the content creator receives the request message, the content creator performs processing such as generation and distribution of the composite content in the same manner as described above.

[2. Configuration and function of Commander Co]
Next, the configuration and function of the commander Co will be described with reference to FIG. FIG. 2C is a block diagram illustrating a schematic configuration example of the commander Co. The commander Co includes a control unit 11, a storage unit 12, a video RAM 13, a video processing unit 14, a display processing unit 15, a microphone control unit 16, a synthesizer 17, a mixing amplifier 18, an operation unit 19a, an operation processing unit 19b, and an infrared reception unit 19c. And a communication unit 19d. The communication unit 19d is connected to the base network NLn. The infrared receiver 19c is for performing infrared communication with the music selection device. The music selection device is a device for a user to perform a music selection operation. The operation processing unit 19b receives a signal output from the operation unit 19a operated by the user or the infrared receiving unit 19c. The operation processing unit 19b is output to the control unit 11.

  The control unit 11 includes a CPU, a ROM, a RAM, and the like. The control unit 11 is an example of a generation unit, a third determination unit, and a distribution unit of the present invention. The storage unit 12 is configured by, for example, a hard disk. The storage unit 12 stores an OS (operating system) and a commander processing program. The control unit 11 performs overall control of the entire commander Co by executing the OS and the commander processing program. The storage unit 12 stores a song ID of a song reserved based on a user's music selection operation. The music ID is, for example, a content ID of a composite content of music.

  In addition, the storage unit 12 stores composite content of music. A content ID and a content type are assigned to the composite content stored in the storage unit 12. The control part 11 performs the reproduction | regeneration process of a music using the synthetic | combination content of a music. In the music reproduction process, the synthesizer 17 decodes the audio data constituting the composite content, for example, reproduces the music, and outputs the audio signal of the music to the mixing amplifier 18. The microphone control unit 16 outputs the user's singing voice signal collected by the microphone to the mixing amplifier 18. The mixing amplifier 18 mixes the audio signal of the music and the singing audio signal and outputs them to the speaker. The video RAM 13 temporarily stores video data constituting the composite content. This video data is, for example, data representing a video in which a lyrics telop is superimposed on a background video. The video processing unit 14 synchronizes with the output of the audio data, decodes the video data stored in the video RAM 13 to reproduce the music, and outputs the video signal of the music to the display processing unit 15. The display processing unit 15 displays the video by outputting the video signal of the music to the display.

  Further, there is a case where the composite content is not stored in the storage unit 12. In this case, as described above, the control unit 11 acquires the component content used for generating the composite content from, for example, another commander Co via the overlay network ON. Thereby, for example, performance data, background video data, and telop data are acquired. And the control part 11 performs the production | generation process of a synthetic content. In the composite content generation process, the control unit 11 outputs the acquired performance data to the synthesizer 17. The synthesizer 17 reproduces the performance data and outputs an audio signal to the control unit 11. The control unit 11 encodes the audio signal from the synthesizer 17 with a predetermined encoding method, for example, to generate audio data. The data format of the audio data may be MP3, AAC, etc., for example. Further, the control unit 11 outputs the acquired background video data to the video RAM 13. Further, the control unit 11 outputs character data constituting the lyrics telop to the video processing unit 14 based on the telop data. The video processing unit 14 superimposes the lyrics telop on the background video using the background video data stored in the video RAM 13 and the character data from the control unit 11, and outputs the video signal to the control unit 11. The control unit 11 generates video data by encoding the video signal from the video processing unit 14 using a predetermined encoding method. The data format of this video data is, for example, MPEG-2, H.264. H.264 or the like may be used. And the control part 11 synthesize | combines the produced | generated audio | voice data and video data, and produces | generates a synthetic content. The component content acquired from another commander Co is stored in the storage unit 12. A content ID is assigned to the component content stored in the storage unit 12. Furthermore, the content ID of the composite content corresponding to the component content may be given to the component content.

  Further, as described above, the control unit 11 executes the composite content distribution process corresponding to the requesting device type. At this time, the composite content corresponding to the device type of the request source may not be stored in the storage unit 12. In this case, the control unit 11 executes a composite content generation process corresponding to the requesting device type.

[3. Configuration and function of node Nk]
Next, the configuration and function of the node Nk will be described with reference to FIG. FIG. 2D is a block diagram illustrating a schematic configuration example of the node Nk. The node Nk includes a control unit 21, a storage unit 22, a communication unit 23, a buffer memory 24, a decoder unit 25, an operation unit 26, and the like. The communication unit 23 is connected to at least one of the backbone network NW and the base network NLn. As described above, the edge server ESn and the portable terminal Tm function as the node Nk by participating in the overlay network ON. In the case of the edge server ESn, the buffer memory 24 and the decoder unit 25 may not be provided. The configuration shown in FIG. 2D can also be applied to the set top box STBp.

  The control unit 21 includes a CPU, a ROM, a RAM, and the like. The control unit 21 is an example of a reception unit, a first determination unit, a second determination unit, and a determination unit of the present invention. The storage unit 22 is composed of, for example, a hard disk drive. The storage unit 22 is an example of a first storage unit and a second storage unit of the present invention. The storage unit 22 stores an OS, a node processing program, and the like. The control unit 21 performs overall control of the entire node Nk by executing the OS and the node processing program. The storage unit 22 stores a routing table using DHT. The node Nk may be the root node of the composite content. In this case, the storage unit 22 stores a composite content holder list and a content creator list. In some cases, the node Nk is the root node of the component content. In this case, the storage unit 22 stores a component content holder list. The buffer memory 24 accumulates the composite content received via the communication unit 23. The decoder unit 25, for example, decodes audio data constituting the synthesized content stored in the buffer memory 24 to reproduce the music, and outputs the audio signal of the music to the speaker. Further, the decoder unit 25 decodes the video data constituting the composite content stored in the buffer memory 24 to reproduce the music, outputs the video signal of the music to the display, and displays the video.

[4. Operation of communication system S]
Next, the operation of the communication system S of the present embodiment will be described.

(4-1. Processing of Commander Co)
First, the process of the commander Co will be described with reference to FIGS. FIG. 3 is a flowchart showing main processing in the control unit 11 of the commander Co. FIG. 4A is a flowchart showing details of the distribution process in step S1 shown in FIG. FIG. 4B is a flowchart showing details of the content type determination process in step S12 shown in FIG. FIG. 5 is a flowchart showing details of the publishing process in step S2 shown in FIG.

  The main process shown in FIG. 3 is started when, for example, the power of the commander Co is turned on. Although not shown, the processing shown in FIG. 3 ends when the power of the commander Co is turned off. The distribution process in step S1 and the publish process in step S2 shown in FIG. 3 will be described later. In step S3, the control part 11 determines whether the music was reserved based on the music selection operation by a user. If it is determined that the music is reserved (step S3: YES), the process proceeds to step S4. On the other hand, when it determines with the music not being reserved (step S3: NO), it returns to step S1.

  In step S <b> 4, the control unit 11 determines whether or not the composite content to which the content ID corresponding to the music ID of the reserved music is assigned is stored in the storage unit 12. When it is determined that the composite content is not stored in the storage unit 12 (step S4: NO), the process proceeds to step S5. On the other hand, when it is determined that the composite content is stored in the storage unit 12 (step S4: YES), the process proceeds to step S9.

  In step S <b> 5, the control unit 11 determines whether or not all of the component content used for generating the composite content determined not to be stored is stored in the storage unit 12. When it is determined that all of the component contents are not stored in the storage unit 12 (step S5: NO), the process proceeds to step S6. That is, if there is not enough component content used to generate the composite content, the process proceeds to step S6. On the other hand, when it is determined that all of the component contents are stored in the storage unit 12 (step S5: YES), the control unit 11 acquires all of the component contents used for generating the composite content from the storage unit 12. Proceed to step S8.

  In step S6, the control unit 11 transmits a request message indicating a request for missing component content to the edge server ESn as described above. And the control part 11 determines whether the component content was received from the content holder of a component content (step S7). If it is determined that the component content has been received (step S7: YES), the process returns to step S5. As a result, the process of step S6 is repeated until all the component contents that are insufficient to generate the composite content are acquired. The acquired component content is stored in the storage unit 12. In step S8, the control unit 11 executes the composite content generation process using the acquired component content as described above, and proceeds to step S9.

  In step S <b> 9, the control unit 11 executes the music reproduction process as described above, using the music composition content. And the control part 11 determines whether the reproduction | regeneration process of a music is complete | finished (step S10). For example, when the reserved music is played to the end of the performance time, it is determined that the music playing process is to be terminated. Alternatively, when the music reproduction end instruction is input by the user, it is determined that the music reproduction process is to be ended. When it is determined that the music reproduction process is to be terminated (step S10: YES), the process returns to step S1. On the other hand, when it is not determined to finish the music reproduction process (step S10: NO), the process returns to step S9. Thereby, the music reproduction process continues.

  Next, in the distribution process of step S1 shown in FIG. 3, as shown in FIG. 4A, the control unit 11 determines whether or not a composite content request message has been received (step S11). If it is determined that the composite content request message has been received (step S11: YES), the process proceeds to step S12. On the other hand, if it is determined that the composite content request message has not been received (step S11: NO), the distribution process ends. Thereby, the process returns to the process shown in FIG. In the distribution process shown in FIG. 4A, the process when a partial content request message is received is omitted.

  In the content type determination process in step S12, as shown in FIG. 4B, the control unit 11 determines the content type of the composite content to be requested based on the device type information included in the received request message ( Step S121). Next, the control unit 11 determines whether or not the determined content type is for a set top box (STB) (step S122). When it is determined that the content type is for the set top box (step S122: YES), the process proceeds to step S123. On the other hand, when it is determined that the content type is not for the set top box (step S122: NO), the process proceeds to step S124. In step S123, the control unit 11 determines the personal video data, the PCM data, and the telop data as the component content used for generating the composite content for the set top box, and ends the content type determination process. Thereby, the process returns to the process shown in FIG. Here, the control unit 11 determines the component content by referring to, for example, a list indicating a correspondence relationship between the content type and the content ID of the component content. Alternatively, the content ID of the component content used for generating the composite content may be included in the composite content request message. It should be noted that normal video data, MIDI data, and telop data may be determined as component content used for generating set-top box composite content.

  In step S124, the control unit 11 determines whether or not the determined content type is for the portable terminal T1. When it is determined that the content type is for the portable terminal T1 (step S124: YES), the process proceeds to step S125. On the other hand, when it is determined that the content type is not for the portable terminal T1 (step S124: NO), the process proceeds to step S126. In step S125, the control unit 11 determines normal video data, PCM data, and telop data as component content used for generating composite content for the portable terminal T1, and ends the content type determination process. Thereby, the process returns to the process shown in FIG.

  In step S126, the control unit 11 determines whether or not the determined content type is for the portable terminal T2. When it is determined that the content type is for the portable terminal T2 (step S126: YES), the process proceeds to step S127. On the other hand, when it is determined that the content type is not for the portable terminal T2 (step S126: NO), the process proceeds to step S128. In this case, it is determined that the content type is for the portable terminal T3. In step S127, the control unit 11 determines normal video data, MIDI data, and telop data as component content used for generating composite content for the portable terminal T2, and ends the content type determination process. Thereby, the process returns to the process shown in FIG. In step S128, the control unit 11 determines MIDI data and telop data as component content used for generating the composite content for the portable terminal T3, and ends the content type determination process. Thereby, the process returns to the process shown in FIG.

  In the content type determination process shown in FIG. 4B, the component content used for the composite content is changed for each of the set-top box, the portable terminal T1, the portable terminal T2, and the portable terminal T3. However, the component content used for the composite content may be shared by a part of the set-top box, the mobile terminal T1, the mobile terminal T2, and the mobile terminal T3. For example, only the component content used for the composite content for the portable terminal T3 may be configured to be different from the others.

  Next, in step S <b> 13 illustrated in FIG. 4A, the control unit 11 determines whether or not the composite content of the determined content type is stored in the storage unit 12. Here, the composite content to be determined is the composite content corresponding to the content ID included in the received request message. And when it determines with the synthetic content of the determined content type not being memorize | stored in the memory | storage part 12 (step S13: NO), it progresses to step S14. On the other hand, when it is determined that the composite content of the determined content type is stored in the storage unit 12 (step S13: YES), the process proceeds to step S18.

  In step S <b> 14, the control unit 11 determines whether or not all of the component contents used for generating the composite content of the determined content type are stored in the storage unit 12. When it is determined that all of the component contents are not stored in the storage unit 12 (step S14: NO), the process proceeds to step S15. That is, if there is not enough component content used to generate the composite content of the determined content type, the process proceeds to step S15. On the other hand, when it is determined that all of the component content is stored in the storage unit 12 (step S14: YES), the control unit 11 acquires all of the component content used for generating the composite content from the storage unit 12. Proceed to step S17.

  In step S15, the control unit 11 transmits a request message indicating a request for missing component content to the edge server ESn, as in step S6. For example, there is a case where only PCM data is not stored in the component content used for generating the composite content for the set top box. In this case, a request message indicating a request for PCM data is transmitted. In this case, for example, the personal video data and telop data other than the PCM data are acquired from the storage unit 12. Then, the control unit 11 determines whether or not the component content is received from the content holder of the component content (step S16). If it is determined that the component content has been received (step S16: YES), the process returns to step S14. The received component content is stored in the storage unit 12. In step S <b> 17, the control unit 11 performs a request target composite content generation process using the acquired component content, and proceeds to step S <b> 18. As a result, composite content corresponding to the requesting device type is generated.

  In step S18, the control unit 11 determines whether or not to deliver the requested composite content to the request source by streaming delivery based on the device type information included in the received request message. For example, when the device type indicated by the acquired device type information is a device type for which caching is restricted, it is determined that the distribution is made to the request source by streaming delivery. Accordingly, for example, even when the composite content cache is restricted at the request source of the composite content, the composite content can be quickly distributed. When it is determined that the composite content is distributed to the request source by streaming distribution (step S18: YES), the process proceeds to step S19. On the other hand, when it is determined that the composite content is not distributed to the request source by streaming distribution (step S18: NO), the process proceeds to step S21.

  In step S19, the control unit 11 distributes the requested composite content to the request source by streaming according to the determination in step S18. Then, the control unit 11 determines whether the distribution of the composite content is completed (Step S20). If it is determined that the distribution of the composite content has not been completed (step S20: NO), the process returns to step S19, and the distribution of the composite content is continued. On the other hand, when it is determined that the distribution of the composite content has been completed (step S20: YES), the distribution process ends. Thereby, the process returns to the process shown in FIG. In step S21, the control unit 11 distributes the requested composite content to the request source by a download method. The process of step S22 is the same as the process of step S20. The composite content distributed in this way is received from, for example, the set top box STBp that is the request source. For example, the set top box STBp reproduces the music using the received composite content.

  Next, in the publishing process in step S2 shown in FIG. 3, as shown in FIG. 5, the control unit 11 determines whether or not there is room for generating the composite content (step S25). Here, as an example of a case where there is a margin for generating the composite content, for example, there is a case where the use frequency of the commander Co including the control unit 11 is equal to or less than a threshold value or a case where the commander Co is not used for a predetermined time. The usage frequency of the commander Co is obtained, for example, by calculating the number of times the commander Co is accessed from another information processing apparatus within a predetermined time. Alternatively, the usage frequency of the commander Co can be obtained, for example, by calculating the number of times the music piece has been played by the commander Co within a certain time. If it is determined that there is room to generate the composite content (step S25: YES), the process proceeds to step S26. On the other hand, when it is determined that there is no room for generating composite content (step S25: NO), the publishing process is terminated. Thereby, the process returns to the process shown in FIG.

  In step S <b> 26, the control unit 11 determines whether or not the synthesized content of the music is stored in the storage unit 12. When it is determined that the composite content is not stored in the storage unit 12 (step S26: NO), the process proceeds to step S28. On the other hand, when it is determined that the composite content is stored in the storage unit 12 (step S26: YES), the process proceeds to step S27.

  In step S27, the control unit 11 transmits the publish message for the composite content holder list to the edge server ESn as described above. Thus, the publish message for the composite content holder list is transmitted to the root node of the composite content via the overlay network ON by the edge server ESn that is the node Nk. When a plurality of composite contents are stored in the storage unit 12, the process of step S27 is performed for each composite content. Further, the process of step S27 may be configured to be executed when the composite content is stored in the storage unit 12 regardless of whether or not there is room for generating the composite content.

  In step S <b> 28, the control unit 11 determines whether or not the component content used for generating the composite content is stored in the storage unit 12. For example, if some component contents are stored in all the component contents used to generate the composite content “AAA”, it is determined that the component contents are stored in the storage unit 12 (step S28: YES). ), Go to step S29. Here, for example, if there are three part contents used for generating composite content, the part contents are one or more part contents or two or more part contents. How many or more are set is set by, for example, a system operator. On the other hand, when it is determined that the component content is not stored in the storage unit 12 (step S28: NO), the publishing process is terminated. Thereby, the process returns to the process shown in FIG.

  In step S29, the control unit 11 transmits a publish message for the content creator list to the edge server ESn as described above. Thereby, the publish message for the content creator list is transmitted to the root node of the composite content via the overlay network ON by the edge server ESn which is the node Nk.

  Next, the control unit 11 transmits a publish message for the component content holder list to the edge server ESn as described above (step S30). Thus, the publish message for the part content holder list is transmitted to the root node of the part content via the overlay network ON by the edge server ESn that is the node Nk. In this way, the distribution process ends, and the process returns to the process shown in FIG. When a plurality of component contents are stored in the storage unit 12, the process of step S30 is performed for each component content. Further, the processing in step S30 may be configured to be executed when the component content is stored in the storage unit 12 regardless of whether or not there is room for generating the composite content.

(4-2. Processing of root node)
Next, the processing of the root node will be described with reference to FIGS. FIG. 6 is a flowchart showing message reception processing in the control unit 21 of the root node. FIG. 7A is a flowchart showing details of the content holder determination process in step S63 shown in FIG. FIG. 7B is a flowchart showing details of the content creator determination process in step S65 shown in FIG. 6 and 7 are flowcharts common to the root node of the composite content and the root node of the component content.

  The message reception process shown in FIG. 6 is started when a message is received. In step S51, the control unit 21 determines whether or not the received message is a publish message. When it is determined that the received message is a publish message (step S51: YES), the process proceeds to step S54. On the other hand, when it is determined that the received message is not a publish message (step S51: NO), the process proceeds to step S52.

  In step S52, the control unit 21 determines whether or not the received message is a request message. When it is determined that the received message is a request message (step S52: YES), the process proceeds to step S63. On the other hand, when it is determined that the received message is not a request message (step S52: NO), the process proceeds to step S53. In step S53, messages other than the publish message and the request message are received. Description of this reception process is omitted.

  In step S54, the control unit 21 determines whether or not the received message is a publish message for the content holder list. When it is determined that the received message is a publish message for the content holder list (step S54: YES), the process proceeds to step S55. On the other hand, when it is determined that the received message is not a publish message for the content holder list (step S54: NO), the process proceeds to step S58. That is, in this case, the received message is a publish message for the content creator list.

  In step S55, it is determined whether the received message is a publish message for the composite content holder list. When it is determined that the received message is a publish message for the composite content holder list (step S55: YES), the process proceeds to step S56. On the other hand, when it is determined that the received message is not a publish message for the composite content holder list (step S55: NO), the process proceeds to step S57. That is, in this case, the received message is a publish message for the parts content holder list.

  In step S56, the control unit 21 acquires the content ID of the composite content, the location information of the commander Co, the content type of the composite content, and the required time for generating the composite content from the publish message for the composite content holder list. Then, the control unit 21 registers the acquired content ID of the composite content, the location information of the commander Co, the content type of the composite content, the time required for generating the composite content, and the like in the composite content holder list in association with each other in step S52. Return.

  In step S57, the control unit 21 acquires the content ID of the component content and the location information of the commander Co from the publish message for the component content holder list. Then, the control unit 21 associates the acquired content ID of the component content, the location information of the commander Co, and the like with each other and registers them in the component content holder list, and returns to step S52.

  In step S58, the control unit 21 acquires the content ID of the composite content, the location information of the commander Co, and the content ID of the component content from the publish message for the content creator list. As described above, the content ID of the component content is the content ID of the component content stored by the commander Co. Then, the control unit 21 registers the acquired content ID of the composite content, the location information of the commander Co, and the content ID of the component content in association with each other in the content creator list.

  Next, the control unit 21 sets an expiration date for the record including the information registered in step S58 (step S59). This expiration date is set, for example, several days after the registration date of location information or the like. Next, the control unit 21 registers the expiration date set in step S59 in the content creator list in association with the location information of the commander Co registered in step S58 (step S60). Next, the control unit 21 determines whether there is an expired record in the content creator list (step S61). If it is determined that there is an expired record in the content creator list (step S61: YES), the process proceeds to step S62. In step S62, the control unit 21 deletes the location information of the commander Co included in the expired record, and returns to step S52. On the other hand, when it is determined that there is no expired record in the content creator list (step S61: NO), the process returns to step S52.

  In step S63, the control unit 21 executes content holder determination processing. In the content holder determination process, as shown in FIG. 7A, the control unit 21 determines whether or not the received request message indicates a request for component content (step S631). When it is determined that the received request message indicates a request for component content (step S631: YES), the process proceeds to step S632. On the other hand, if it is determined that the received request message does not indicate a request for component content (step S631: NO), the process proceeds to step S634. In other words, in this case, the received request message indicates a request for composite content.

  In step S632, the control unit 21 acquires the content ID of the requested component content and the location information of the information processing apparatus from the request message indicating the request for the component content. Next, the control unit 21 determines a component content holder as a distribution device that distributes the component content to the request source based on the content ID acquired in step S632 and the component content holder list (step S633). The determination process ends. Thereby, the process returns to the process shown in FIG. The component content holder determined in step S633 is a component content holder corresponding to the location information associated with the content ID acquired in step S632 and registered in the component content holder list. The location information of the distribution device thus determined is acquired from the component content holder list.

  In step S634, the control unit 21 acquires the content ID of the requested composite content, the location information of the information processing device, and the device type information indicating the device type of the information processing device from the request message indicating the request for the composite content. . Next, the control unit 21 determines whether or not a usage condition for using the content holder as a distribution device is satisfied (step S635). This content holder is a content holder of the composite content to which the content ID acquired in step S634 is assigned. For example, when the reception time of the request message is included in a midnight time zone with a short access time, it is determined that the use condition is satisfied. As a result, it is possible to generate composite content by effectively using idle time. Further, when the number of content holders registered in the composite content holder list is a predetermined number or more, it is determined that the use condition is satisfied. This means that the content holder is not used when the number of content holders is small. Thereby, the load of the content holder of the composite content can be reduced.

  Further, when the information of the content holder registered in the composite content holder list is newer than the past predetermined date and time, it is determined that the usage condition is satisfied. This is to the effect that the content holder is not used when the information of the content holder registered in the composite content holder list is old. Thereby, since the content creator can generate and distribute the composite content, the composite content can be kept up-to-date. Whether or not the content holder information is newer than a predetermined date in the past is determined by, for example, the update date and time registered in the composite content holder list. There may be a plurality of target content holders. In this case, it may be configured to determine that the usage condition is satisfied when information of a predetermined number or more of content holders among them is newer than a past predetermined date and time. In this case, only content holders determined to be newer than a predetermined date and time in the past are candidates to be determined as distribution devices.

  Further, when the number of accesses to the content holder registered in the composite content holder list is equal to or less than the predetermined number, it is determined that the usage condition is satisfied. This means that the content holder is not used when the number of accesses to the content holder is large. Thereby, the load of the content holder of the composite content can be reduced. The number of accesses of the content holder registered in the composite content holder list is managed by the root node of the composite content. Each time the root node of the composite content determines the content holder as a distribution device according to the request message, the root number of the content holder is incremented. There may be a plurality of target content holders. In this case, if the number of accesses to a predetermined number or more of the content holders is less than the predetermined number, it may be configured to determine that the usage condition is satisfied. In this case, only content holders for which the number of accesses is determined to be equal to or less than the predetermined number are candidates to be determined as distribution devices.

  And when it determines with satisfy | filling the usage conditions which use a content holder as a delivery apparatus (step S635: YES), it progresses to step S636. On the other hand, when it is determined that the usage conditions for using the content holder as a distribution device are not satisfied (step S635: NO), that is, when it is determined that the content holder is not usable, the processing returns to the processing illustrated in FIG.

  In step S636, the control unit 21 stores a content holder that stores the composite content corresponding to the device type indicated by the device type information acquired in step S634 among the content holders determined to satisfy the usage conditions in step S635. It is determined whether or not there is. Here, “whether there is a content holder” means whether the location information of the content holder is registered in the composite content holder list. Whether the content is a composite content corresponding to the device type indicated by the device type information acquired in step S634 is a content registered in the composite content holder list in association with the content ID acquired in step S634. Determined by type. If it is determined that the location information of the content holder that stores the composite content corresponding to the device type is registered (step S636: YES), the process proceeds to step S637. On the other hand, when it is determined that the location information of the content holder that stores the composite content corresponding to the device type is not registered (step S636: NO), that is, when it is determined that the content holder is not usable, the content holder The determination process ends. Thereby, the process returns to the process shown in FIG.

  In step S637, the control unit 21 determines whether or not the holder registration date and time of the content holder for which the location information has been registered in step S636 is within a predetermined period retroactive from the present time. This means that the content holder is not used when the holder registration date / time of the content holder is old. When it is determined that the holder registration date and time of the content holder is within a predetermined period retroactively from the present time (step S637: YES), the process proceeds to step S638. On the other hand, when it is determined that the holder registration date / time of the content holder is not within the predetermined period retroactively from the current time (step S637: NO), that is, when it is determined that the content holder is not usable, the content holder determination process is performed. finish. Thereby, the process returns to the process shown in FIG.

  In step S638, the control unit 21 determines the content holder for which the holder registration date / time is determined to be within the predetermined period in step S637 as a distribution device that distributes the composite content to the request source, and the content holder determination process ends. . Thereby, the process returns to the process shown in FIG. Here, there may be a plurality of content holders for which it is determined that the holder registration date / time is within a predetermined period. In this case, among the plurality of content holders, the content holder having the smallest number of accesses may be determined as the distribution device. The location information of the distribution device determined in this way is acquired from the composite content holder list.

  In step S64 shown in FIG. 6, the control unit 21 determines whether or not the distribution device has been determined by the content holder determination process. When it is determined that the distribution device has not been determined (step S64: NO), that is, when it is determined that the content holder is not usable, the process proceeds to step S65. On the other hand, when it is determined that the distribution device has been determined (step S64: YES), the process proceeds to step S66.

  In step S65, the control unit 21 executes content creator determination processing. In the content creator determination process, as shown in FIG. 7B, the control unit 21 determines whether a plurality of pieces of location information of the content creator associated with the content ID acquired in step S634 are registered in the content creator list. Is determined (step S651). If it is determined that a plurality of pieces of content creator location information are not registered in the content creator list (step S651: NO), that is, if there is only one content creator, the process proceeds to step S652. On the other hand, if it is determined that a plurality of pieces of content creator location information are registered in the content creator list (step S651: YES), the process proceeds to step S653.

  In step S652, the control unit 21 determines the content creator corresponding to the location information determined in step S651 as a distribution device that generates the composite content and distributes it to the request source, and the content creator determination process ends. Thereby, the process returns to the process shown in FIG. The location information of the distribution apparatus determined in this way is acquired from the content creator list.

  In step S653, the control unit 21 selects a predetermined number of content creators that store more part content among the plurality of part contents used to generate the composite content identified by the content ID acquired in step S634. Then, it is determined as a distribution device that generates the composite content and distributes it to the request source, and the content creator determination process ends. Thereby, the process returns to the process shown in FIG. The content creator determined in step S653 is determined from the content creators corresponding to the plurality of pieces of location information determined in step S651. In addition, the predetermined number of content creators that store more part content is the higher number of content IDs of the part content associated with each of the plurality of pieces of location information determined in step S651 in the content creator list. A content creator corresponding to location information. As a result, the content creator can quickly complement the component content that is insufficient in the component content necessary for generating the composite content. Therefore, the content creator can promptly generate the requested composite content.

  In step S66, the control unit 21 transfers the received request message to the distribution device determined by the content holder determination process or the content creator determination process. Alternatively, the control unit 21 may be configured to return a response message including the location information of the distribution device determined by the content holder determination process or the content creator determination process to the request source as described above.

  As described above, according to the present embodiment, the root node that manages the location of the content holder and content creator of the composite content is the content holder of the composite content corresponding to the requesting device type in response to the request for the composite content. It is determined whether or not is available. When the root node determines that the content holder of the composite content is not usable, the root node is configured to determine a content creator capable of generating the composite content as a distribution device that distributes the composite content to the request source. Therefore, it is possible to quickly provide composite content corresponding to the request source device type to a request source that is an information processing apparatus that does not have the ability to generate composite content.

  In addition, according to the above-described embodiment, even when access is concentrated on the content holder of the composite content, the content creator generates the composite content corresponding to the requesting device type of the composite content and distributes it quickly. can do. Further, even if the number of content holders of the composite content is small, the content creator can generate the composite content corresponding to the device type that requested the composite content and distribute it quickly.

  In the above embodiment, the composition content of music has been described as an example. However, the present invention can also be applied to composite content other than music composite content. In the above embodiment, the performance data, the background video data, and the telop data have been described as examples of the material data. However, the present invention can also be applied to material data other than performance data, background video data, and telop data.

  Moreover, in the said embodiment, although the peer to peer network using DHT was applied to the overlay network, it is not restricted to this. For example, another peer-to-peer system or a system using an overlay network may be applied. As an overlay network that does not use DHT, for example, there is a hybrid peer-to-peer network system.

ESn Edge server Tm Mobile terminal Co Commander STBp Set top box ON Overlay network S Communication system

Claims (5)

An information processing apparatus capable of communicating via an overlay network composed of a plurality of information processing apparatuses connected to a network,
Identification information of composite content generated using a plurality of material data obtainable via the overlay network, first location information indicating a location of a first information processing apparatus that stores the composite content, and First storage means for storing in association with first type information indicating the type of information processing apparatus to which the composite content corresponds;
Second storage means for storing the identification information of the composite content and second location information indicating the location of the second information processing apparatus capable of generating the composite content using the plurality of material data in association with each other When,
Identification information of the composite content transmitted via the overlay network with the third information processing device as a transmission source, and third location information indicating the location of the third information processing device that reproduces the composite content; Receiving means for receiving second type information indicating a type of the third information processing apparatus;
The second type information received by the receiving unit and the first type information stored in the first storage unit in association with the identification information of the composite content received by the receiving unit. First determination means for determining whether or not the first information processing device storing the composite content corresponding to the type of the third information processing device is usable,
When it is determined by the first determination means that the first information processing apparatus is not usable, the first information processing apparatus is stored in the second storage means in association with the identification information of the composite content received by the reception means. Determining means for determining the second information processing apparatus corresponding to the second location information as an information processing apparatus for generating the composite content;
An information processing apparatus comprising: In the second storage means, identification information of the material data stored in each of the plurality of second information processing apparatuses capable of generating the composite content is stored in association with the second location information. And
The information processing apparatus determines whether or not a plurality of pieces of the second location information associated with the identification information of the composite content received by the receiving unit are stored in the second storage unit. Further comprising means,
When it is determined by the second determination means that a plurality of the second location information is stored in the second storage means, the determination means is identified by the identification information of the composite content received by the reception means Of the plurality of material data identification information used for generating the composite content to be performed, the higher-order second location information having a large number of identification information of the material data associated with the second location information The information processing apparatus according to claim 1 , wherein the second information processing apparatus corresponding to is determined as an information processing apparatus that generates the composite content.   The information processing apparatus receives the identification information of the composite content, the third location information of the third information processing apparatus, and the second type information received by the receiving means by the determining means. The information processing apparatus according to claim 1, further comprising: a transmission unit configured to transmit to the second information processing apparatus when it is determined. Identification of composite content generated using a plurality of material data that is communicable via an overlay network composed of a plurality of information processing devices connected to the network and that can be acquired via the overlay network Information, first location information indicating the location of the first information processing apparatus that stores the composite content, and first type information indicating the type of the information processing apparatus to which the composite content corresponds are associated with each other. Corresponding first storage means for storing, identification information of the composite content, and second location information indicating a location of a second information processing apparatus capable of generating the composite content using the plurality of material data A second storage means for storing the information;
Identification information of the composite content transmitted via the overlay network with the third information processing device as a transmission source, and third location information indicating the location of the third information processing device that reproduces the composite content; Receiving a second type information indicating a type of the third information processing apparatus;
The second type information received by the receiving step and the first type information stored in the first storage unit in association with the identification information of the composite content received by the receiving step. A first determination step of determining whether or not the first information processing device storing the composite content corresponding to the type of the third information processing device is usable,
When it is determined in the first determination step that the first information processing apparatus is not usable, the first information processing apparatus is stored in the second storage unit in association with the identification information of the composite content received in the reception step. A determination step of determining the second information processing apparatus corresponding to the second location information as an information processing apparatus for generating the composite content;
A program characterized by having executed. A communication system including an information processing apparatus capable of communicating via an overlay network composed of a plurality of information processing apparatuses connected to a network,
An information processing apparatus capable of communicating via the overlay network is:
Identification information of composite content generated using a plurality of material data obtainable via the overlay network, first location information indicating a location of a first information processing apparatus that stores the composite content, and First storage means for storing in association with first type information indicating the type of information processing apparatus to which the composite content corresponds;
Second storage means for storing the identification information of the composite content and second location information indicating the location of the second information processing apparatus capable of generating the composite content using the plurality of material data in association with each other When,
Identification information of the composite content transmitted via the overlay network with the third information processing device as a transmission source, and third location information indicating the location of the third information processing device that reproduces the composite content; Receiving means for receiving second type information indicating a type of the third information processing apparatus;
The second type information received by the receiving unit and the first type information stored in the first storage unit in association with the identification information of the composite content received by the receiving unit. First determination means for determining whether or not the first information processing device storing the composite content corresponding to the type of the third information processing device is usable,
When it is determined by the first determination means that the first information processing apparatus is not usable, the first information processing apparatus is stored in the second storage means in association with the identification information of the composite content received by the reception means. Determining means for determining the second information processing apparatus corresponding to the second location information as an information processing apparatus for generating the composite content;
With
The second information processing apparatus that receives the identification information of the composite content, the third location information of the third information processing apparatus, and the second type information from the information processing apparatus,
Generating means for generating composite content identified by the received identification information of the composite content;
Third determination means for determining whether to deliver the composite content generated by the generation means to the third information processing apparatus by streaming distribution based on the received second type information;
Distribution means for distributing the composite content to the third information processing apparatus in accordance with the determination by the third determination means;
A communication system comprising:

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