JP2007274243A - Content data distribution system, content data distribution method, terminal device and operation program of the terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a content distribution system and a content distribution method capable of reducing a time from a channel switching operation by a user to playback start of content data, as much as possible, while preventing increase of load over a network in a broadcasting type content distribution system, and to provide a terminal device and an operation program for the terminal device. <P>SOLUTION: The broadcasting type content distribution system, where a plurality of channels with each distributing content data in streaming to a user via a network, is configured so that the content data are received in radio communication, until the connection between a terminal device and a device for distributing the content data is completed, afte the user performs channel switching operation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a content data distribution system, a content data distribution method, a terminal device, and an operation program for the terminal device.

  In recent years, content distribution services for streaming distribution of content data (hereinafter referred to as “content data”) such as music, movies, and talk programs have started to be started via networks such as the Internet. Here, the streaming distribution is a distribution method for distributing content data in a streaming format that can be stream-received by a client terminal device (hereinafter simply referred to as “terminal device”). You can play while receiving. Further, as a streaming distribution form, there are a broadcast format in which a distribution time of content data is determined and an on-demand format in which streaming distribution is performed to individual terminal devices in response to a request from the terminal device.

  Conventionally, a content distribution service in a broadcast format has been mainly used to directly distribute content from a single content distribution device to a plurality of terminal devices.

  However, with the enhancement of content distribution services and the increase in the number of terminal devices connected to the network, the number of terminal devices that request content data distribution from the content distribution devices increases, and the load on the content distribution devices increases. In addition, the concentration of traffic in the network has had a serious impact.

  In order to avoid such an increase in load and traffic on the content distribution device, a technology for distributing the load by placing a plurality of servers such as mirror servers and caches in the network in addition to the original distribution server has been put into practical use. However, a plurality of servers for distributing contents are required, and the cost of facilities increases.

  Therefore, a content data distribution system has been proposed that can reduce load and traffic concentration without increasing the number of content distribution devices by relaying content data between terminal devices, that is, using a P2P communication mode.

  In this content data distribution system, a plurality of terminal devices are logically connected in multiple layers in a tree structure with the content distribution device at the top, and content data is sequentially distributed from the content distribution device to downstream terminal devices.

  That is, the content data distributed from the content distribution device is distributed to the terminal device located in the highest layer (first layer), and the terminal device located in the highest layer receives the content data distributed from the content distribution device. Relaying is performed to the terminal device located in the second hierarchy, and this content data is relayed to the terminal device located in the lowest layer.

  Usually, in such a content data distribution system, a connection management device for logically connecting a plurality of terminal devices in a tree structure is arranged on a network.

  The connection management device has a function of managing the connection state of the terminal devices in the hierarchical structure of the content distribution system, and forms a hierarchical structure when receiving a participation request from a terminal device not participating in the hierarchical structure. One of the plurality of terminal devices is selected and notified to the terminal device that made the participation request.

  The terminal device that has received this notification can participate in the content distribution system by making a connection request to the connection destination candidate that has been introduced by the connection management device. It can be received via an upstream terminal device.

  By the way, in the content data distribution system in the broadcast format, when content data is streamed and distributed by a plurality of channels, a tree-type hierarchical structure having the content distribution device as a vertex is configured for each channel.

  Therefore, when the user of the terminal device performs an operation to view content data of a channel different from the channel being viewed, a tree-type hierarchical structure different from the tree-type hierarchical structure corresponding to the channel being viewed Will participate in.

  However, when the user of the terminal device switches the viewing channel, it takes a lot of time to participate in the tree-type hierarchical structure of the switching destination channel.

  That is, when the user performs an operation to switch channels, the terminal device performs processing for having the connection management device introduce other terminal devices that are connection destinations in the new hierarchical structure, or NAT (Network Address Translation). It is necessary to perform processes that exceed the limit, and it is not possible to participate in a new hierarchical structure until these processes are completed, and even if the user performs an operation to switch channels, the connection destination cannot be switched immediately. .

As a method for dealing with such a problem, a terminal device can be newly created from a channel switching operation by a user by superimposing and distributing summary data (content data for countermeasures against zapping) on content data on content data. A content distribution system using an information browsing method that shortens the time until connection to a terminal device is proposed (see, for example, Patent Document 1).
JP 2003-324711 A

  If the content data for zapping measures is superimposed on the content data in order to shorten the channel switching time, the amount of data exchanged on the Internet network will increase accordingly. This is a nuisance to other users.

  Accordingly, the present invention provides a content data distribution system and a content data distribution method capable of further reducing the time from when a user performs a channel switching operation to reproduction of content data without imposing a load on the network. It is an object of the present invention to provide a terminal device and an operation program for the terminal device.

  Therefore, in the present invention according to claim 1, one or more content distribution devices that respectively distribute content data through a plurality of channels via a network, and a plurality of terminal devices that receive and reproduce the content data via a network, And a connection management device for managing a plurality of terminal devices so as to be logically connected in a hierarchical structure on a network with the content distribution device as a vertex for each channel, and content data streamed from the content distribution device is In a content data distribution system that sequentially relays downstream in a hierarchical structure by a relay function of a terminal device for each channel, the content distribution device includes distribution means for streaming distribution of content data, and the connection management device has a hierarchy for each channel. Make up structure When connection state information storage means for storing connection state information of the terminal device and a connection destination introduction request from the terminal device are received, a connection destination candidate is selected from the connection state information stored in the connection state information storage means, and the connection A connection destination candidate notification means for notifying a destination candidate to the terminal device that has transmitted the connection destination introduction request, the terminal device, a channel selection means for selecting a channel, a distribution device on the network, a connection management device, A communication means comprising: a first communication means for communicating with another terminal apparatus; and a second communication means for communicating with another terminal apparatus adjacent to the other terminal apparatus via a route different from the network by transmitting and receiving a radio signal; A connection destination introduction request relating to the channel selected by the channel selection means is transmitted to the connection management device via the first communication means, and then the connection management device. A connection means for connecting to the connection destination candidate notified from the first communication means, a first reception means for receiving content data from the connected connection destination candidate via the first communication means, and a neighbor other via the second communication means. Adjacent terminal information acquisition means for acquiring terminal information including the channel number selected by the terminal device, and when the channel is selected by the channel selection means, the channel number acquired by the adjacent terminal information acquisition means is the channel selection means. Content of the channel selected by the channel selection means via the second communication means when the judgment means judges that the channel number matches with the judging means for judging whether or not the channel number selected by Requests other terminal devices to stream data and receives content data from other terminal devices A second receiving unit that reproduces the content data received by the second receiving unit until the content data received by the first receiving unit is reproduced after the channel is selected by the channel selecting unit; A relay unit that receives a content data relay request from another terminal device via the first communication unit and transfers the content data received via the first communication unit to the terminal device that has made the relay request; It is characterized by that.

  Further, in the present invention according to claim 2, one or more content distribution devices that respectively distribute content data through a plurality of channels via a network, and a plurality of terminal devices that receive and reproduce the content data via a network, And a connection management device for managing a plurality of terminal devices so as to be logically connected in a hierarchical structure on a network with the content distribution device as a vertex for each channel, and content data streamed from the content distribution device is In a content data distribution method in a content data distribution system that relays downstream in a hierarchical structure sequentially by a relay function of a terminal device for each channel, the content distribution device includes a step of streaming distribution of content data, and the connection management device includes: , A step of storing connection state information of terminal devices constituting a hierarchical structure for each channel in the connection state information storage means, and connection state information stored in the connection state information storage means when receiving a connection destination introduction request from the terminal device Selecting a connection destination candidate from the terminal, and notifying the connection destination candidate to the terminal device that has transmitted the connection destination introduction request, the terminal device detecting a channel selection, and a distribution device on the network A connection destination introduction request regarding the channel selected by the channel selection means is transmitted to the connection management apparatus via the first communication means for communicating with the connection management apparatus and other terminal apparatuses, and then notified from the connection management apparatus. Connecting to the connected destination candidate, receiving content data from the connected destination candidate via the first communication means, Acquiring terminal information including a channel number selected by another adjacent terminal device via a second communication means for communicating by transmitting and receiving wireless signals via a route different from the network; A step of determining whether or not the acquired channel number matches the selected channel number when selected, and a channel selected via the second communication means when it is determined that the channel number matches Requesting other terminal devices to perform streaming distribution of the content data, receiving the content data from the other terminal devices, and after reproducing the content data received from the connection destination candidate after the channel is selected Reproducing the content data received from another terminal device, via the first communication means Receiving a relay request for the content data from another terminal device, and transferring the received content data via the first communication means to the terminal device that has made the relay request.

  Further, in the present invention according to claim 3, one or more content distribution devices that respectively distribute content data through a plurality of channels via a network, and a plurality of terminal devices that receive and reproduce the content data via a network, And a connection management device for managing a plurality of terminal devices so as to be logically connected in a hierarchical structure on a network with the content distribution device as a vertex for each channel, and content data streamed from the content distribution device is In a terminal device in a content data distribution system that sequentially relays downstream of the hierarchical structure by the relay function of the terminal device for each channel, a channel selection means for selecting a channel, a distribution device on the network, and connection management Equipment and other terminals Communication means having first communication means for communicating with a device, and second communication means for communicating with other terminal devices adjacent to each other on a route different from the network by transmitting and receiving radio signals, and first communication A connection means for transmitting a connection destination introduction request regarding the channel selected by the channel selection means to the connection management device, and then connecting to the connection destination candidate notified from the connection management device; and a first communication means. Via the first receiving means for receiving the content data from the connected connection destination candidate and the adjacent terminal for obtaining the terminal information including the channel number selected by the other adjacent terminal device via the second communication means When the channel is selected by the information acquisition unit and the channel selection unit, the channel number acquired by the adjacent terminal information acquisition unit is the channel number. Determining means for determining whether or not the channel number selected by the selecting means matches, and the channel selected by the channel selecting means via the second communication means when the determining means determines that the channel numbers match. The second receiving means for requesting the streaming distribution of the content data to the other terminal device and receiving the content data from the other terminal device, and the channel is selected by the channel selecting means and then received by the first receiving means. Until the content data is reproduced, the content data received by the second receiving means is received via the first communication means and the reproducing means for receiving the content data from another terminal device, and the relay request is received. A relay means for transferring the content data received via the first communication means to the terminal device that has performed It is characterized by doing.

  In the present invention according to claim 4, in the terminal device according to claim 3, when the determination unit determines that the channel numbers match, the connection unit of the terminal device selects the channel by the channel selection unit. And waiting for a predetermined period to connect to a connection destination candidate.

  Further, in the present invention according to claim 5, in the terminal device according to claim 4, the terminal device includes an average reproduction time detection unit that detects an average reproduction period by the reproduction unit regarding content data for each channel, and the terminal The connection means of the apparatus is characterized in that an average reproduction period is set as a predetermined period to connect to the connection destination candidate.

  Further, in the present invention according to claim 6, in the terminal device according to claim 4 or claim 5, when the connection means of the terminal device cannot acquire terminal information by the adjacent terminal information acquisition means, or determination means When it is determined that the channel numbers do not match, the channel selection means connects to the connection destination candidate without waiting for a predetermined period after the channel is selected.

  Moreover, in this invention which concerns on Claim 7, in the terminal device of any one of Claim 4 to 6, the said connection means of a terminal device is within a predetermined period, after a channel is selected by a channel selection means. Further, when another channel is selected by the channel selection means, connection to a connection destination candidate for the channel is not performed.

  Moreover, in this invention which concerns on Claim 8, in the terminal device of any one of Claim 4-7, a terminal device is another terminal device from the terminal information acquired by the adjacent terminal information acquisition means of the terminal device. Is connected to a NAT (network address replacement) router, the NAT (NAT) of the NAT router necessary for establishing a communication connection between the other terminal device and the own terminal device before the connection operation by the connection means is determined. It has a NAT table setting means for setting a network address replacement table.

  Further, in the present invention according to claim 9, in the terminal device according to any one of claims 4 to 8, whether or not the terminal information can be connected to another terminal device via a network. Whether or not the terminal device can be connected to another terminal device receiving content data by the second receiving unit via the network based on the terminal information acquired by the adjacent terminal information acquiring unit. A connection determination unit for determining whether or not the connection unit of the terminal device determines that the connection determination unit can connect to the other terminal device via the first communication unit. It is characterized by connecting.

  Further, in the present invention according to claim 10, in the terminal device according to claim 9, a router that detects the number of routers between another terminal device that is determined to be connectable by the connection possibility determination unit and the own terminal device Among the other terminal devices that are determined to be connectable by the connection possibility determination unit, the terminal unit connection unit includes a terminal device in which the number of routers detected by the router number detection unit is equal to or less than a predetermined value. When connecting to the other terminal device via the first communication means, and when the number of routers is larger than a predetermined value, it is connected to the connection destination candidate via the first communication means.

  Moreover, in this invention which concerns on Claim 11, in the terminal device of Claim 9, it is communication which detects the communication time between the other terminal device determined to be connectable by the connection possibility determination means, and a self-terminal device Among the other terminal devices that are determined to be connectable by the connectability determination unit, the connection unit of the terminal device includes a terminal device whose communication time detected by the communication time detection unit is a predetermined value or less. When connecting to the terminal device via the first communication means, and when the communication time is longer than a predetermined value, the terminal device is connected to the connection destination candidate via the first communication means.

  Moreover, in this invention which concerns on Claim 12, in the terminal device of any one of Claim 4 to 10, 2nd communication means, channel selection means, adjacent terminal information acquisition means, determination means, The reproduction means is housed in at least the first unit, and the first communication means, the connection means, the first reception means, the relay means, and the third communication means for performing wireless communication with the first unit are at least the second unit. The second communication means is configured to be capable of wireless communication with the third communication means.

  In the present invention according to claim 13, a program for causing a computer to function as each unit of the terminal device according to any one of claims 4 to 12 is provided.

  According to the present invention, the following effects can be obtained. That is, according to the present invention according to claim 1, in a broadcast-type content data distribution system that distributes content data to a user via a network through a plurality of channels, a channel switching operation by the user is performed. Until the connection by wire communication between the terminal device and the device that distributes content data is completed, the content data can be received by wireless communication, so that the user can perform channel switching operation without imposing a load on the network. It is possible to provide a content data distribution system capable of smoothly switching between channels by shortening the time until content data is reproduced as soon as possible.

  According to the second aspect of the present invention, in the content data distribution method in the broadcast-type content data distribution system in which content data is stream-distributed to a user via a network through a plurality of channels, the channel switching operation by the user is performed. Since the content data can be received by wireless communication until the connection by wire communication between the terminal device and the device that distributes the content data is completed, the user can perform the operation without imposing a load on the network. It is possible to provide a content data distribution method capable of smoothly switching channels by shortening the time from when a channel switching operation is performed until the content data is reproduced as much as possible.

  According to the third aspect of the present invention, in a terminal device used by a user in a broadcast-type content data distribution system that distributes content data to a user via a network through a plurality of channels, the user channel is set. The content data can be received by wireless communication until the connection by wire communication between the terminal device and the device that distributes the content data is completed after the switching operation is performed, so that there is no load on the network. Thus, it is possible to provide a terminal device capable of smoothly switching channels by shortening the time from when a user performs channel switching operation until content data is reproduced as much as possible.

  According to the fourth aspect of the present invention, in consideration of the state in which the adjacent terminal device detected by the second communication means is watching the channel designated by the user by channel selection, the first time is waited for a predetermined period. Since the connection destination candidate acquired via the communication means is connected, disturbance to the logical connection relationship of the hierarchical structure constituting the distribution route of the content data in the content distribution system can be reduced.

  Further, according to the present invention of claim 5, since the predetermined time shown in claim 4 is determined in consideration of the past viewing state by the user, it is performed before the streaming reception of the content by the first communication means. The predetermined time for content streaming reception by the second communication means can be appropriately determined.

  Further, according to the present invention of claim 6, even if the other terminal receiving the content data selected by the user does not exist in a geographically close position, the content that the user surely desires Data can be received.

  According to the seventh aspect of the present invention, the start of streaming reception of content by the first communication means is reserved when a zapping state in which channel switching is frequently performed in a short time is detected. It is possible to reduce disturbance to the hierarchical logical connection relationship constituting the content data distribution path in the distribution system.

  Further, according to the present invention of claim 8, while receiving content data of a channel desired by the user by wireless communication, connection by wired communication is performed using the terminal information acquired by the adjacent terminal information acquisition means. Therefore, it is possible to perform the setting process of the NAT table necessary for this, so that it is possible to further shorten the time from when the channel switching operation is performed by the user until the content data is reproduced.

  According to the present invention of claim 9, when it is determined from the adjacent terminal information obtained by the second communication means that it is possible to connect directly to the adjacent terminal device via the first communication means. Since the connection management apparatus directly connects to the adjacent terminal device without issuing the connection destination introduction request to the connection management device and acquiring the connection destination, the issue of the connection destination introduction request to the connection destination introduction device is not concentrated.

  Further, according to the present invention according to claims 10 and 11, the first communication means is provided only when it is determined from the adjacent terminal information obtained by the second communication means that the adjacent terminal device is close to the network. Since the direct connection is made via the first communication means, the load applied to the network after connecting to the terminal device via the first communication means can be reduced. It can also contribute to communication speed and stability.

  According to the twelfth aspect of the present invention, in carrying out the inventions of the fourth to twelfth aspects, the unit 1 of the terminal device that performs wired communication by connecting to a network device or the like, and the user uses a remote controller or the like. Since the housing of the unit 2 that receives the instruction sent via the terminal can be separated, it is possible to improve the convenience of using the terminal device to the user.

  According to a thirteenth aspect of the present invention, in a broadcast-type content data distribution system that distributes content data to a user via a network using a plurality of channels, the user channel without burdening the network. It is possible to provide an operation program for a terminal device that can further reduce the time from when the switching operation is performed until the content data is reproduced.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best embodiment of the invention will be described based on the drawings. The embodiment described below is a content distribution system with a tree structure using P2P, in which content data distributed from a content distribution apparatus in a broadcast format is P2P by a terminal device that configures a tree-like hierarchical structure. This is an embodiment in which the present invention is applied to a broadcast-type content distribution system that is used and received.

[1. Content distribution system configuration]
First, a schematic configuration and the like of the content distribution system S will be described with reference to FIG.

  FIG. 1 is a diagram illustrating a schematic configuration example of a content distribution system S according to the present embodiment. As shown in FIG. 1, a content distribution system S according to the present embodiment is a broadcast content distribution system, and a plurality of distribution channels (hereinafter simply referred to as “channels”) for separately streaming distribution of a plurality of content data. "). For example, in one channel, a plurality of terminal devices 2a1, 2a2, 2b1-2b4, 2c1-2c8 are logically connected in a tree-like hierarchical structure with the content distribution device 1 as a vertex, and content data is received from the content distribution device 1. The tree structure is configured to be streamed from the upper layer to the lower layer. The other channels (2 channels to n channels) have the same configuration.

  In addition, in the case of indicating any one terminal device or all terminal devices of the terminal devices 2a1, 2a2, 2b1-2b4, 2c1-2c8 (in FIG. 4, the terminal devices 2d1, 2d2, 2e1-2e4, 2f1), In some cases, it is referred to as a terminal device 2.

  Further, the content distribution system S has a connection management device 3, and this connection management device 3 manages the tree-like hierarchical structure of each channel.

  An IP address is assigned to each of the content distribution device 1, the terminal devices 2a1, 2a2, 2b1 to 2b4, 2c1 to 2c8, and the connection management device 3, and these devices are connected to the Internet 4 as an example of a network, a router 10 and the like. Connected through. In other words, communication connection is possible by transmitting a packet including a header with the destination IP address of the target terminal device as the destination IP address and the IP address of the own device as the source IP address.

  The connection management device 3 may be included in the content distribution device 1. In this case, the connection management apparatus 3 may not be assigned an IP address, and may be shared with the IP address of the content distribution apparatus 1. In addition, the content distribution apparatus 1 may distribute content data of a plurality of channels (here, channel 1 to n channel) constituting the content distribution system S, while content for each channel. A distribution device 1 may be provided. In the present embodiment, the content distribution device 1 is provided for each channel, the first content distribution device 1a1 performs streaming distribution of content data of one channel, and the second content distribution device 1a2 performs content of two channels. A description will be given assuming that data is distributed by streaming (see FIG. 4).

  Also, the first layer terminal devices 2a1, 2a2 and 2d1, 2d2 are for convenience, respectively, the terminal devices 2a, 2d, and the second layer terminal devices 2b1-2b4 and 2e1-2e4 are respectively, for convenience, the terminal devices 2b, 2e, and third. The hierarchical terminal devices 2c1 to 2c8 and 2f1 may be referred to as terminal devices 2c and 2f, respectively, for convenience.

  In this content distribution system S, a plurality of terminal devices 2 are logically connected in multiple layers in a tree-like hierarchical structure with the first and second content distribution devices 1a1, 1a2 as apexes (here, for convenience, the 0th layer). In this way, the connection management device 3 manages the connection. In the present embodiment, a tree-like hierarchical structure is described. However, the present invention is not limited to this, and a plurality of terminal devices 2 may be logically connected in multiple layers in a chain-like hierarchical structure.

  When the connection management device 3 receives a connection destination introduction request from the terminal device 2 that does not participate in the content distribution system S, in other words, from the terminal device 2 that does not constitute a tree-like hierarchical structure, the connection management device 3 Based on the state of the structure and the like, a connection destination candidate (content distribution device 1 or terminal device 2) to be connected as an upstream terminal device for the terminal device 2 to receive streaming distribution is selected. Then, the location information of the connection destination candidate selected in this way (such as the IP address and port number of the connection destination candidate) and the communication protocol are notified.

  In the content distribution system S, when the communication protocol and the port number are already fixed, the port number and the communication protocol to the terminal device 2 need not be notified. Here, MMS (Microsoft Media Server) protocol, RTSP (Real Time Streaming Protocol), etc. are used as communication protocols. As the format of the content data, ASF (Advanced Streaming Format), WMA (Windows (registered trademark) Media Audio), WMV (Windows (registered trademark) Media Video), or the like is used.

  When the terminal device 2 receives the location information of the connection destination candidate from the connection management device 3, the terminal device 2 requests the connection destination candidate of the IP address to participate (connect) to the content distribution system S, thereby the terminal device 2 Are incorporated into the hierarchical structure in the content distribution system S. That is, the terminal device 2 can receive the content data distributed from the content distribution device 1.

  In the content distribution system S, when the terminal devices 2 participate one after another in this manner, a plurality of terminal devices 2 are logically connected in a multilayered manner in a tree-like hierarchical structure with the content distribution device 1 as a vertex. Then, the content data distributed from the content distribution device 1 is sequentially relayed to the lower terminal device 2 by the relay function of the terminal device 2 and streamed to the plurality of terminal devices 2.

  That is, as shown in FIG. 1, in one channel, content data is transmitted from the content distribution device 1 to the terminal devices 2a1, 2a2 (first layer terminal devices), and the terminal devices 2a1, 2a2 receive the content data. The received content data is sequentially relayed to the lower-layer terminal devices 2b1 to 2b4 (second-layer terminal devices). When the terminal devices 2b1 to 2b4 receive the content data, the terminal device 2b1 to 2b4 sequentially relays the received content data to the lower-layer terminal devices 2c1 to 2c8 (third-layer terminal devices).

  The terminal device 2 stores the location information of the upper-layer terminal device 2 or the content distribution device 1 at the position of the incorporated hierarchical structure and the location information of the lower-level terminal device 2 at the position in the main storage device 207 to be described later. Based on the stored location information, content data is relayed. Further, the content data to be distributed is divided into a plurality of packets and sequentially distributed, and the data thus divided and distributed is called a content packet.

  Thus, the content data distributed to the terminal device 2 is distributed to all the terminal devices 2 participating in the content distribution system S. In addition to content data such as music and movies, the content data to be distributed includes playback time information (hereinafter referred to as “playback time data”). Then, the plurality of terminal devices 2 that have received the content data perform the reproduction of the content data that is sequentially transmitted based on the reproduction time data.

  In this way, the content distribution system S can distribute the content data transmitted from the content distribution device 1 to the plurality of terminal devices 2 and reproduce the content at the same time on the plurality of terminal devices 2. That is, the broadcast streaming distribution to the plurality of terminal devices 2 is realized using P2P.

  As described above, the content distribution system S in the present embodiment has a plurality of channels for streaming distribution of a plurality of content data respectively. The user of the terminal device 2 selects a desired channel, and acquires from the connection management device 3 the connection destination device (hereinafter referred to as “connection destination candidate”) of the terminal device 2 in the selected channel. Then, by connecting to the connection destination candidate, it participates in the hierarchical structure of the desired channel, receives the content data from the device located above the own terminal device 2 in this hierarchical structure, and plays (hereinafter referred to as “viewing”). Say.)

  Thus, after the terminal device 2 participates in a hierarchical structure of a certain channel, the user of the terminal device 2 may switch the channel. When the user selects a channel that is different from the channel currently being viewed and performs channel switching (hereinafter also referred to as “zapping”), the terminal device 2 in the conventional content distribution system S uses the channel being joined. Withdrawing from the hierarchical structure, participation in the hierarchical structure of the channel selected by the user is performed according to the above-described procedure.

  Conventionally, when joining from a hierarchical structure of a participating channel to another channel hierarchical structure, a process for receiving connection destination candidate information from the connection management device 3, and for connecting to the connection destination candidate A series of connection processing such as NAT (network address translation) crossing processing has been performed. For this reason, in the terminal device 2 in the conventional content distribution system S, there has been a state in which the content data is not reproduced for the time until the content data of the switching destination channel is received and reproduced. Such a period in which the content data is not reproduced (blank period) becomes a factor that makes the user of the terminal device 2 uncomfortable.

  Therefore, the terminal device 2 in the present embodiment periodically performs wireless communication with a plurality of other terminal devices (hereinafter referred to as “neighboring terminal devices”) 2 installed in geographically close locations. By performing various types of information related to the adjacent terminal device 2 (hereinafter referred to as “terminal information”) including location information of the plurality of adjacent terminal devices 2 on the network, and when the user performs zapping Refers to the terminal information, searches for the adjacent terminal device 2 that is receiving the content data distributed on the channel selected by the user, and receives the content data from the corresponding adjacent terminal device 2 by wireless communication for a predetermined period. Like to do.

[2. Explanation of channel switching method]
Whether or not the terminal device 2 is connectable to the downstream side of the adjacent terminal device 2 transmitting the content data while receiving the content data from the adjacent terminal device 2 by wireless communication. If it is determined that the connection is possible, a process for zapping is performed, and after the process is completed, a connection is made to the downstream side of the adjacent terminal device 2 that is transmitting the content data, and wired Content data is received by communication.

  FIG. 2 is an explanatory diagram showing a communication form by wire and wireless communication of each terminal device 2 in the present embodiment. As shown in FIG. 2, each terminal apparatus 2 is connected to a wired telephone line cable or the like, and the content distribution apparatus distributes content data of a channel desired by the user via the telephone line cable or the like. By connecting to one or another terminal device 2, desired content data distributed from the connected content distribution device 1 or other terminal device 2 can be received and viewed.

  Furthermore, each terminal device 2 performs wireless communication between neighboring terminal devices 2 periodically (for example, every minute) using radio waves such as a wireless LAN, so that information on the terminal device 2 is obtained. Is transmitted to the adjacent terminal device 2 as terminal information, and terminal information is received from a plurality of adjacent terminal devices 2.

  And the adjacent terminal information transmitted from the several adjacent terminal device 2 is memorize | stored sequentially in each terminal device 2, and is updated whenever new terminal information is transmitted.

  FIG. 3 is an explanatory diagram illustrating an example of adjacent terminal information stored in the terminal device 2, and here, terminal information regarding seven adjacent terminal devices 2 is illustrated.

  As shown in FIG. 3, the terminal information is divided into six items: device number, location information, connected channel, downstream connection availability, pop count, and RTT (Round Trip Time). In the apparatus, these six items are stored and managed in correspondence with each adjacent terminal apparatus 2.

  Here, the terminal number is a unique number assigned to each terminal device 2.

  The location information is information indicating the location of each adjacent terminal device 2 on the network, and the outside (Internet side) of the NAT router assigned to the local address used in the priority communication by the adjacent terminal device 2. Adoreless (global address).

  The connected channel is information indicating the channel number of the channel to which the adjacent terminal device is currently connected.

  Further, whether or not downstream connection is possible is a flag indicating whether or not each adjacent terminal device 2 can connect a new other terminal device 2 to the downstream side in the hierarchical structure of the own terminal device 2.

  The number of pops is information indicating the number of routers 10 through which the terminal device 2 passes when information is transmitted to and received from the adjacent terminal device 2 on the network.

  The RTT is information indicating a time from when a packet is transmitted from the own terminal device 2 to an adjacent terminal device until returning to the own terminal device 2 again.

  Here, the number of pops and the RTT are measured by transmitting / receiving measurement packets to / from the adjacent terminal device 2 via wired communication using the location information obtained as the adjacent terminal information by the terminal device 2.

  Then, each terminal device 2 searches for the adjacent terminal device 2 connected to the channel selected by the user based on this terminal information when the channel switching operation is performed by the user, and the adjacent that hits this search Until a connection is established with the terminal device 2 by wire communication, content data is received by wireless communication from the adjacent terminal device 2 that has hit the search, and the user performs an operation for zapping. The time until the content data distributed on the channel selected by the user is reproduced is made as short as possible.

  Here, referring to FIGS. 4 and 5, channel switching (zapping) in the present embodiment will be described in more detail.

  FIG. 4 is an explanatory diagram showing a hierarchical structure in which 1-channel content data is streamed and a hierarchical structure in which 2-channel content data is streamed, and FIG. It is explanatory drawing which looked at zapping in the flow of time.

  As shown in FIG. 4, a hierarchical structure with the first content distribution device 1a1 (layer 0) as the apex is constructed on the channel 1 side, and a terminal device 2a1 that forms one layer in the first content distribution device 1a1. 2a2 are connected. In addition, terminal devices 2b1 and 2b2 constituting two layers are connected to the terminal device 2a1, and terminal devices 2b3 and 2b4 constituting two layers are connected to the terminal device 2a2.

  A terminal device 2c1 constituting a third layer is connected to the downstream side of the two-layer terminal device 2b4. Here, the terminal device 2c1 will be described as the own terminal device 2 before zapping.

  Further, on the 2 channel side, a hierarchical structure with the second content distribution device 1a2 (layer 0) as a vertex is constructed, and terminal devices 2d1 and 2d2 constituting one layer are connected to the second content distribution device 1a2. ing. Further, terminal devices 2e1 and 2e2 constituting two layers are connected to the terminal device 2d1, and terminal devices 2e3 and 2e4 constituting two layers are connected to the terminal device 2d2. Note that the terminal device 2f1 connected downstream of the two-tier terminal device 2e1 on the two-channel side shows a state where the terminal device 2c1 before zapping has joined the hierarchical structure on the two-channel side by performing zapping. Here, it is called the self-terminal device 2f1 after zapping.

  Now, assume that the user of the terminal device 2c1 before zapping who participates in the hierarchical structure of one channel and views the content data distributed from the first content distribution device 1a1 performs an operation of selecting two channels. .

  Here, the self-terminal device 2c1 before zapping determines whether there is an adjacent terminal measure 2 that is currently receiving content data distributed from the second content distribution device 1a2 of two channels.

  At this time, it is possible to determine whether or not there is a proximity terminal measure 2 that receives content data of two channels by using the terminal information shown in FIG. 3 as a determination criterion.

  That is, the self-terminal device 2c1 before zapping first refers to the connected channel item in the terminal information and determines whether there is an adjacent terminal device 2 that is currently receiving content data of two channels. .

  In FIG. 4, the two-layer terminal device 2e1 in the two-channel layer structure is the adjacent terminal device 2 of the own terminal device 2c1 before zapping, and is the terminal device 2 that is currently receiving content data of two channels. Shall.

  As shown in FIG. 4, when there is an adjacent terminal device 2e1 that is receiving 2-channel content data, wireless communication is started with the adjacent terminal device 2e1, and the adjacent terminal device 2e1 Two-channel content data is received and reproduced using wireless communication.

  That is, the self-terminal device 2c1 before zapping requests the adjacent terminal device 2e1 to request stream transmission by wireless communication of content data of two channels. The adjacent terminal device 2e1 that has received this stream transmission request assigns (assigns) an empty channel for wireless communication for stream transmission and establishes a wireless communication connection with the terminal device 2c1 that has transmitted the stream transmission request. .

  Then, the transmission of the two-channel content data received via the wired communication from the terminal device 2d1 currently connected upstream is started to the terminal device 2c1 that has transmitted the stream transmission request.

  Then, the terminal device 2c1 that has received the two-channel content data from the adjacent terminal device 2e1 by wireless communication decodes and reproduces the content data by the decoder.

  Note that when the own terminal device 2c1 determines that there is an adjacent terminal device 2e1 that is receiving the content data of the channel (here, 2 channels) selected by the user, the own terminal device 2c1 is in contact with the adjacent terminal device 2e. The NAT traversal process necessary for connection by wired communication is performed in advance.

  Here, the NAT traversal process means that the local terminal apparatus 2c1 can send an IP packet to the adjacent terminal apparatus 2e1 with the outside of the router 10 to which the adjacent terminal apparatus 2e1 is connected as the destination, and the local terminal apparatus 2c1. Is a process for allowing the adjacent terminal device 2e1 to send an IP packet to the own terminal device 2c1 with the outside of the router 10 connected to In other words, this process is a process of storing a communication connection between two terminal apparatuses 2 (in this case, between the own terminal apparatus 2c1 and the adjacent terminal apparatus 2e1) to be communicated by wire communication in the NAT table of the NAT router. Yes, for example, when communicating using UDP (User Datagram Protocol), UDPHolePunching that achieves the above-mentioned purpose by simultaneously transmitting an IP packet from the terminal device 2c1 and the adjacent terminal device 2e1 to the other terminal device 2 Use the so-called technology.

  After that, as shown in FIG. 5, if the user's zapping operation is not performed while the reception of the content data by wireless communication is continued for a predetermined (fixed) time, the own terminal device 2c1 receives the current reception. Connection processing for performing wired communication with the neighboring terminal device 2e1 that is the transmission source of the content data being started is started.

  As described above, in the terminal device 2 according to the present embodiment, after reception of content data by wireless communication continues for a predetermined time, the connection processing for performing wired communication with the neighboring terminal device 2e1 is started frequently. Therefore, it is possible to prevent the hierarchical logical connection relation from becoming unstable due to the fact that zapping is performed.

  Here, the own terminal device 2c1 refers to the terminal information shown in FIG. 3 again, and the adjacent terminal device 2e1 currently receiving the stream distribution of the content data by wireless communication can connect to the downstream side in the hierarchical structure. It is determined whether or not it is in a state.

  That is, the local terminal device 2c1 refers to the item of whether or not the downstream connection is possible for the adjacent terminal device 2e1, and determines whether or not the flag indicating whether or not the downstream terminal of the adjacent terminal device 2e1 indicates OK.

  At this time, if it is determined that the flag indicating whether downstream connection is possible or not, the degree of proximity of the terminal device 2c1 on the network with reference to the number of pops and the RTT related to the adjacent terminal device 2 Judge whether or not is high.

  Here, when the number of pops is equal to or smaller than a predetermined threshold and the RTT is equal to or smaller than the predetermined threshold, it is determined that the proximity on the network is high.

  As a result, when it is determined that the number of pops is equal to or smaller than a predetermined threshold and the RTT is equal to or smaller than the predetermined threshold, the adjacent terminal device 2 is currently distributed from the second content distribution device 1a2 of two channels. The content data is being received and it is determined that the adjacent terminal measure 2 can be connected to the downstream side, and processing for establishing a connection by wired communication with the adjacent terminal device 2e1 is started.

  Then, when the processing for establishing the connection by wired communication is completed, the local terminal device 2c1 before zapping, as shown in FIG. 4, is based on wired communication with the adjacent terminal device 2e1 as the local terminal device 2f1 after zapping. Connection is established. After that, the terminal device 2f1 after zapping transmits a request to transmit the content data stream by wired communication to the adjacent terminal device 2e1.

  Upon receiving this stream transmission request, the adjacent terminal device 2e1 registers the terminal device 2f1 that has transmitted the stream transmission request as a terminal device 2 connected downstream, and as shown in FIG. The content data of two channels received from the terminal device 2d1 connected to is transmitted by wired communication.

  When the content data starts to be received by wired communication, the terminal device 2f1 after zapping decodes and reproduces the received content data.

  As described above, according to the terminal device 2 of the present embodiment, from when the zapping operation is performed by the user, until the user participates in the hierarchical structure of the channel selected by the user and receives and reproduces the content data by wired communication. Since the content data is received and reproduced by wireless communication from the adjacent terminal device 2 that is receiving from the upstream terminal device 2, the user performs the zapping operation, The time until playback of the content data of the selected channel can be shortened as much as possible, and smooth zapping can be performed.

  In addition, since the terminal device 2 does not superimpose and distribute summary data (content data for zapping countermeasures) related to other channels on the content data as seen in the conventional terminal technology, it is transmitted to the Internet by P2P communication. There is no load.

  In addition, here, there is an adjacent terminal device 2e1 that is receiving the content data of the channel selected by the user who performed the zapping operation, and the adjacent terminal device 2e1 connects its own terminal device 2c1 that performs zapping downstream. Although the case where it was possible was described, even if there is no adjacent terminal device 2e1 receiving content data of the channel selected by the user in the geographical vicinity of the own terminal device 2c1, When the adjacent terminal device 2e1 cannot connect the terminal device 2 to the downstream side, or when the terminal device 2 can be connected, but the proximity on the connected terminal device 2 on the network is low, The normal connection described below is performed.

  That is, when performing a normal connection, the terminal device 2 first connects to the connection management device 3, and from the connection management device, another terminal device 2 or content that can distribute the content data of the channel selected by the user. A candidate for the distribution apparatus 1 is acquired.

  Next, the terminal device 2 uses the above-described NAT traversal to establish a wired communication connection with a device selected from the acquired candidates (another terminal device 2 or content distribution device 1). Processing is performed, and the degree of proximity on the network with a device that has established a connection by wired communication is measured.

  That is, the number of pops and RTT relating to a device that has established a connection by wired communication are acquired, and if the number of pops and RTT are equal to or less than a predetermined threshold set for each, a stream transmission request is transmitted to that device. If the number of pops or RTT is larger than a predetermined threshold, the above NAT processing and proximity measurement on the network are repeated for other candidates.

  The device that has received the stream transmission request registers the terminal device 2 that has transmitted the stream transmission request as a device connected to the downstream side, and starts transmitting content data to the terminal device 2.

  When receiving the content data, the terminal device 2 decodes and reproduces the received content data.

  Further, as shown in FIG. 5, the self-terminal device 2c1 is connected to the adjacent terminal device 2e1 by wired communication after a predetermined time has elapsed since the reception of content data from the adjacent terminal device 2e1 by wireless communication. However, the present invention is not limited to this. For example, as shown in FIG. 6, when the terminal device 2c1 starts receiving content data from the adjacent terminal device 2e1 by wireless communication. Alternatively, the connection processing for performing communication by wire communication with the adjacent terminal device 2e1 may be started immediately, and the stream transmission by the adjacent terminal device 2e1 may be stopped immediately when the connection processing is completed.

  In this case, the time for participating in the distribution route formed by wired communication is shortened.

Further, the zapping interval of each terminal device 2 is managed together with the terminal information in advance, and connection processing for performing communication by wired communication from the start of content data stream transmission by wireless communication according to the average time of the zapping interval It may be possible to set the time until starting to be variable,

  By doing so, as shown in FIG. 7, the time from the start of content data stream transmission by wireless communication to the start of connection processing for performing communication by wired communication can be variably set. Thereby, the switching process according to the action characteristic regarding a user's channel switching is realizable. .

Hereinafter, specific configurations and operations of the content distribution device 1, the terminal device 2, and the connection management device 3 constituting the content distribution system S will be described with reference to the drawings.
[3. Description of Content Distribution Device 1 Configuration]
Next, the configuration and operation of the content distribution apparatus 1 will be described with reference to FIG.

  FIG. 8 is a diagram illustrating a schematic configuration example of the content distribution apparatus 1 according to the present embodiment. The content distribution apparatus 1 can be applied to a general server computer, and as shown in FIG. 8, a CPU (Central Processing Unit) 302 and a main rewritable main storage apparatus that stores (stores) various programs and the like. A storage device 305, a hard disk device 303 that stores various data, a network interface 304 that communicates with the terminal device 2 and the connection management device 3 via the Internet 4, and a keyboard 307 that can input predetermined information. The image data is received from the peripheral device control chip 306 that controls the input means such as the mouse 308 and the CPU 302 and written in the internal video memory (not shown), and the data written in the video memory is displayed on the display 310 described later. Video chip 309 and the video chip 309 A display 310 that performs display in accordance with the received signal, a sound source chip 311 having a sound source such as an FM sound source (Frequency Modulation) or a Wave Table sound source, and a built-in speaker 312 that converts an audio signal output from the sound source chip 311 into sound waves. These various components are connected to each other via a system bus 301.

  The network interface 304 is connected to the Internet 4 via the router 320. This router 320 corresponds to the router 10 shown in FIG.

  In the present embodiment, the CPU 302 and the main storage device 305 constitute a control unit 330. The content distribution apparatus 1 is connected to the display (liquid crystal display or the like) 310 as described above. For example, a broadcast operator who operates the content distribution system S sees the display 310. However, it is possible to input predetermined information from the input means.

(About main memory 305)
Further, the main storage device 305 takes out the OS (Operating System) program 317 for providing basic functions as a computer of the content distribution device 1 and the content data stored in the hard disk device 303 to extract the terminal device 2. Control the stream control program 315 for streaming to the network, the topology management program 316 for managing the location information (IP address, port number, etc.) of each terminal device 2 of each floor structure for each channel, and the display 310 Screen control program 318 for decoding, decoder program 319 for decoding encoded content data, decoding content data of broadcast content 313, and broadcast program read from hard disk device 303 Content 313 stores the ring buffer 314 for temporarily storing before transmitting to the terminal device 2, they are retrieved by the CPU 302, and functions according to the program by the CPU 302 is executed.

  Here, the OS program 317 is read out and executed by the CPU 302, so that the content distribution apparatus 1 such as a function related to input / output of the keyboard 307 and the mouse 308 and the memory management of the main storage device 305 and the hard disk device 303. It enables the basic functions of a computer to be executed.

  Then, with the OS program 317 being executed by the CPU 302, the above-described stream control program 315, topology management program 316, screen control program 318, and decoder program 319 are read from the main storage device 305 and executed.

  The OS program 317, the stream control program 315, the topology management program 316, the screen control program 318, the decoder program 319, and the like may be downloaded to the main storage device 305 from a server connected to the Internet 4, for example. Alternatively, after being recorded on a recording medium such as a CD-ROM, it may be read into the main storage device 305 via a drive of the recording medium.

(Regarding the controller 330)
The control unit 330 is configured by the CPU 302 and the main storage device 305 as described above, and the CPU 302 reads out and executes various programs 315 to 319 stored in the main storage device 305 to control the entire content distribution device 1. It controls and functions as a distribution means described later. It should be noted that the CPU 302 executes the stream control program 315 to serve as distribution means, the CPU 302 executes the topology management program 316, the topology management means, and the CPU 302 executes the screen control program 318. As the display control means or the like, the CPU 302 executes the decoder program 319 so as to function as a reproduction means.

(About distribution means)
The distribution unit takes out the designated content data from the broadcast content 313 by an input unit such as a keyboard 307, and performs streaming distribution to the terminal device 2a on the first layer through the network interface 304.

  Streaming delivery to the terminal device 2a and the like by this delivery means is executed according to the following procedure.

  The distribution means sequentially extracts content data corresponding to the preset content from the broadcast content 313 and stores it in the ring buffer 314.

  Next, the distribution unit encodes the content data extracted from the ring buffer 314 into a data format for streaming distribution, for example, a data format such as ASF, WMA, WMV.

  Thereafter, the distribution means stores the corresponding content data in the content packet while dividing the corresponding content data for each predetermined capacity, and transmits it to the content packet via the network interface 304. .

(Topology management means)
In the content distribution device 1, one channel is allocated to one content distribution device 1, and the topology management unit participates in the first layer of the tree-like hierarchical structure configured in the allocated channel. 2 location information (IP address, port number, etc.) is managed. The above distribution means distributes content data to the terminal apparatus 2 using the IP address of the terminal device 2 managed by the topology management means as the destination address and the distribution IP address as the transmission source.

(Display control means)
The display control means has a function of controlling the video chip 309 and the display 310 to display content data and various information. In other words, the display control unit can control how the content video and various types of information are displayed on the display 310.

(About playback means)
The reproduction means has a function of displaying content data from the broadcast content 313 on the display 310 and outputting it from the built-in speaker 312.

[3. Description of Configuration of Terminal Device 2]
Next, the configuration and operation of the terminal device 2 will be described with reference to FIG.

  FIG. 9 is a diagram illustrating a schematic configuration example of the terminal device 2 in the present embodiment. As the terminal device 2, a general personal computer or a dedicated terminal can be applied. As shown in FIG. 9, a CPU (Central Processing Unit) 202 and a rewritable main storage device 207 for storing (storing) various programs and the like. And a hard disk device 203 for storing various data and the like, and a first communication for wired communication between the content distribution device 1, the connection management device 3, and the other terminal device 2 on the network via the Internet 4. A network interface 206 that functions as a communication means, a user-input remote controller 210 that transmits and receives a predetermined infrared signal for the user to remotely operate the terminal device 2, and communication with the user-input remote controller 210 by infrared rays. Infrared port 209 and peripheral device control for controlling infrared port 209 The image data is received from the chip 208 and the CPU 202, written to an internal video memory (not shown), and the data written to the video memory is displayed on a built-in display 212 described later, and transmitted from the video chip 211. A built-in display 212 that performs display according to a signal to be transmitted, a sound source chip 213 having a sound source such as an FM sound source (Frequency Modulation) or a Wave Table sound source, and a built-in speaker 214 that converts an audio signal output from the sound source chip 213 into sound waves. These various components are connected to each other via a system bus 201.

  In addition, the system bus 201 of the terminal device 2 transmits and receives radio signals to and from another terminal device (adjacent terminal device) 2 installed in a location geographically close to the terminal device 2. Is connected to a wireless communication interface 204 functioning as a second communication means for communicating via a route different from the network of the Internet 4, and an antenna 205 for transmitting and receiving wireless signals is connected to the wireless communication interface 204. Yes.

  In the terminal device 2, the wireless communication interface 204 and the network interface 206 constitute communication means.

  In the present embodiment, the CPU 202 and the main storage device 207 constitute a control unit 230. The network interface 206 is connected to the Internet 4 via the router 223. This router 223 corresponds to the router 10 shown in FIG.

  Here, the remote controller 210 for user input has a channel selection button (not shown) as channel selection means for selecting a channel of the content distribution system S, and the user of the terminal device 2 uses the channel selection button. It can be connected to a desired channel.

(About the main storage device 207)
The main storage device 207 is stream-distributed by the OS program 219 for providing the basic function of the terminal device 2 as a computer and the content distribution device 1 directly or relayed to another terminal device 2. Stream control program 216 for receiving and streaming content data to the downstream terminal device 2 and location information (IP address and port number) of the upstream terminal device 2 (or content distribution device 1) connected in a tree A topology control program 217 for managing location information of a terminal device 2 further downstream in a tree connection, a screen control program 220 for controlling the built-in display 212, and content data stream-received from an upstream device For decoding and playing Network program 221, terminal information management program 222 for storing and managing the terminal information of the above-described adjacent terminal device 2, and the adjacent terminal device 2 and other terminal devices 2 connected by wired communication on the network And a terminal device monitoring program 218 for monitoring terminal information update information and the like, which are read by the CPU 202, and the function according to these programs is executed by the CPU 202.

  In addition, the main storage device 207 sequentially stores the content data received by streaming, and there is content data that has been reproduced from the stored content data and another terminal device 2 connected downstream. Is provided with a ring buffer 215 for sequentially erasing the content data that has been distributed to the terminal device 2.

  Here, the OS program 219 is read and executed by the CPU 202, thereby causing the terminal device 2 such as a function relating to input / output of the remote controller 210 for user input or memory management such as the main storage device 207 and the hard disk device 203 to perform. It enables the basic functions of a computer to be executed. While the OS program 219 is executed by the CPU 202, the above-described stream control program 216, topology control program 217, screen control program 220, decoder program 221, terminal information management program 222, terminal device monitoring program 218, etc. are the main ones. It is read from the storage device 207 and executed.

  Note that the OS program 219, the stream control program 216, the topology control program 217, the screen control program 220, the decoder program 221, the terminal information management program 222, the terminal device monitoring program 218, and the like are obtained from, for example, a server connected to the Internet 4. It may be downloaded to the main storage device 207, or may be recorded on a storage medium such as a CD-ROM and then read into the main storage device 207 via a drive of the storage medium.

(About the control unit 230)
The control unit 230 includes the CPU 202 and the main storage device 207 as described above, and the CPU 202 reads out and executes the various programs 216 to 222 stored in the main storage device 207, thereby performing overall control of the terminal device 2 as a whole. And connecting means, first receiving means, second receiving means, adjacent terminal information obtaining means, determination means, reproduction means, relay means, average reproduction time detection means, NAT table setting means, connection possibility determination means, which will be described later, It functions as router number detection means, communication time detection means, and the like.

  The CPU 202 executes the stream control program 216 as first receiving means, second receiving means, relay means, etc., and the CPU 202 executes the topology control program 217, thereby connecting means, topology management means, NAT table. As a setting means, a relay request receiving means, etc., as a display control means by the CPU 202 executing the screen control program 220, and as a reproducing means by the CPU 202 executing the decoder program 221, the CPU 202 further manages terminal information. By executing the program 222 and the terminal device monitoring program 218, the adjacent terminal information acquisition means, determination means, average reproduction time detection means, connection availability determination means, router number detection means, communication time detection means, etc. It is adapted to function.

(About connection means)
In order to cause the terminal device 2 to participate in the content distribution system S, the connection means issues a connection destination introduction request regarding the channel selected by the user's operation of the channel selection button of the user input remote control 210 as the channel selection means. 3 and then connect to the connection destination candidate notified from the connection management device 3.

  More specifically, the connection means transmits a connection destination introduction request to the connection management device 3 to register the terminal device 2 in the connection management device 3 in order to cause the terminal device 2 to participate in the content distribution system S. Has a function of requesting connection destination candidates. This connection destination introduction request includes information specifying a channel selected by the user of the terminal device 2 operating a channel selection button or the like of the user input remote controller 210, location information of the terminal device 2, and the like.

  Further, the connection means, when the user of the terminal device 2 performs a channel switching operation by operating the user input remote controller 210 or the like while the terminal device 2 is connected to a certain channel, the switching operation To the adjacent terminal device 2 satisfying a predetermined condition among the adjacent terminal devices 2 participating in the hierarchical structure of the channel to be newly connected.

  As a result, the terminal device 2 can switch the connection from one channel to a new channel. Instead of providing the channel switching button of the user input remote controller 210, the display control means described later may be operated to display a channel selection screen on the display, and the user input remote controller 210 may be selected.

  Further, the connection means responds to the connection destination introduction request transmitted to the connection management device 3, and information on the connection destination candidate notified from the connection management device 3, that is, the IP address that is the location information of the terminal device of the connection destination candidate, It has a function of receiving information such as a port number (hereinafter may be abbreviated as “connection destination candidate” including information on connection destination candidates).

  Further, the connection unit has a function of connecting to the connection destination candidate based on the received information about the connection destination candidate. In other words, the connection means makes a connection request with the destination IP address and port number as the destination based on the information about the destination candidate, and makes a logical connection with the destination candidate. By connecting to the connection destination candidate in this way, it is possible to incorporate the own terminal device 2 into a part of the tree-like hierarchical structure.

(About the first receiving means)
The first receiving means receives content data from another terminal device 2 or content distribution device 1 that is a connection destination candidate connected via the network interface 206, and more specifically, further upstream in the hierarchical structure. The content packet stream-distributed from the terminal device 2 or the content distribution device 1 is received.

(Neighboring terminal information acquisition means)
The adjacent terminal information acquisition unit acquires terminal information including channel numbers selected by the plurality of adjacent terminal devices 2 via the wireless communication interface 204. Specifically, as shown in FIG. 3, information on the device number of the adjacent terminal device, location information, connected channel, downstream connection availability, pop count, RTT, and the like is acquired.

(About judgment means)
The determination means determines whether or not the channel number acquired by the adjacent terminal information means matches the channel number selected by the user input remote control 210 when a channel is selected by the user's operation of the user input remote control 210. Determine.

  That is, the determining means refers to the terminal information to determine whether or not there is an adjacent terminal device 2 that is currently receiving the content data of the channel selected by operating the user input remote controller 210. Judgment.

  When it is determined by the determining means that the channel numbers match, the connecting means selects a channel by the user's operation of the remote controller for user input 210 and then selects the channel number from the adjacent terminal device 2 having the matching channel number. The second receiving unit waits for a predetermined period during which content data is received via the wireless communication interface 204, and then connects to the adjacent terminal device 2 that is a connection candidate via the network interface 206.

(About the second receiving means)
When the determination unit determines that the channel numbers match, the second reception unit performs streaming distribution of the content data of the channel selected by the operation of the user input remote control 210 by the user via the wireless communication interface 204. A request is made to the adjacent terminal device 2 determined to match the channel number, and content data is received from the adjacent terminal device 2.

(About playback means)
The reproduction means has a function of sequentially storing and sequentially reproducing the content data stream-received by the wireless communication interface 204 or the network interface 206 in the ring buffer 215.

  Then, the reproduction means receives the content data received via the wireless communication interface 204 until the content data received by the network interface 206 is reproduced after the channel is selected by the user's operation of the remote controller 210 for user input. Play.

  This reproducing means realizes this function by operating the sound source chip 213 and the video chip 211, and sequentially retrieves the content data stored in the ring buffer 215 and converts it into a predetermined content data format (for example, Wave format). The content is converted and input to the sound source chip 213 and the video chip 211 to reproduce the content.

  When the content data includes audio information, the content data converted into a predetermined content data format by the reproduction means is output from the built-in speaker 214 after the audio information is converted into an audio signal by the sound source chip 213. The

  In addition, when the content data converted into a predetermined content data format by the reproduction means includes video information, the video information is displayed on the built-in display 212 under the control of the display control means described later.

  Further, the reproduction means determines the timing for reproducing the content data based on the reproduction start time information included in the content data stored in the ring buffer 215. That is, the playback means is configured to output the content data stored in the ring buffer 215 to the built-in speaker 214 or the built-in display 212 at the playback start time.

(About relay means)
The relay unit receives a content data relay request from another terminal device 2 via the network interface 206 and transfers the content data received via the network interface 206 to the other terminal device 2 that has made the relay request. To do.

  In addition, when the relay unit receives a relay request from the adjacent terminal device 2 via the wireless communication interface 204, the relay unit first transmits the content data to the adjacent terminal device 2 that has made the relay request via the wireless communication interface 204. Content data by wireless communication via the wireless communication interface 204 when the connection means establishes a connection by wired communication between the own terminal device 2 and the adjacent terminal device 2 that has made a relay request. Is stopped, and content data transfer via wired communication via the network interface 206 is started.

(Average playback time detection means)
The average playback time detection means detects an average playback period by the playback means regarding content data for each channel.

  That is, this average reproduction time detecting means detects, for each channel, the average time for which each adjacent terminal device 2 continuously receives the content data of one channel.

  Then, the connection means waits for the content data to be received from the adjacent terminal device 2 via the wireless communication interface 204 by the second receiving means during the average reproduction period detected by the average reproduction time detection means, The adjacent terminal device 2 is connected by wired communication via the network interface 206.

  However, the connection means detects the average reproduction time when the adjacent terminal information acquisition means cannot acquire the terminal information of the adjacent terminal device 2 that is a connection candidate, or when the determination means determines that the channel numbers do not match. Without waiting for the average reproduction period detected by the means, the terminal is connected to another terminal device 2 that is a connection destination candidate notified from the connection management device 3 via the network interface 206.

  The connection means further operates the operation of the user input remote control 210 within the average reproduction period detected by the average reproduction time detection means after the channel is selected by the user's operation of the user input remote control 210. Thus, when another channel is selected, connection is not made to another terminal device 2 that is a connection destination candidate for the other channel.

(About NAT table setting means)
When the NAT table setting means determines that the other terminal apparatus 2 is connected to the NAT (network address replacement) router from the location information in the terminal information acquired by the adjacent terminal information acquisition means, before the connection operation by the connection means, The NAT table of the NAT router necessary for establishing communication connection between the other terminal device 2 and the own terminal device 2 is set.

  That is, the NAT table setting means stores a communication connection between two terminal apparatuses 2 (in this case, between the own terminal apparatus 2 and the adjacent terminal apparatus 2) that perform communication by wired communication in the NAT table of the NAT router. In the case of communication using UDP (User Datagram Protocol), the NAT terminal is set by transmitting an IP packet from the terminal device 2 and the adjacent terminal device 2 to the partner terminal device 2 at the same time.

  The NAT traversal processing performed by the NAT table setting means is not limited to this. For example, a method of setting a NAT table of a NAT router as defined in the UPnP standard, RFC3489: Simple Traversal of UDP through NAT For example, a method using UDP defined in the above, a method using a STUN server, a Terede server, or the like may be used.

  Specifically, when performing NAT traversal processing using UPnP, the NAT table setting means transmits a port number mapping generation request to the NAT router.

  When the NAT router receives the port number mapping generation request from the terminal device 2, the NAT router associates the local IP address in the terminal device 2 with the predetermined port number on the Internet side of the NAT router and registers it in the NAT table.

  By setting the NAT table in this way, when a communication packet including the NAT router's IP address and its predetermined port number is received by the NAT router, the NAT table is referred to and the terminal corresponding to this predetermined port number is referred to. The communication packet is port-forwarded to the device 2.

  After performing NAT traversal according to the UPnP standard in this way, the terminal devices inform each other of the port numbers set in the NAT table so that the P2P connection between the terminal devices can be established immediately.

(About connectability determination means)
Based on the terminal information acquired by the adjacent terminal information acquisition means, the connection possibility determination means connects to another adjacent terminal device 2 receiving the content data by the second reception means by wired communication via the network. It is determined whether or not

  That is, when the connection possibility determination means indicates that the downstream connection possibility flag, which is information indicating whether or not it is possible to connect to another terminal device 2 included in the terminal information via the network, indicates OK. Is determined to be connectable, and if the downstream connection enable / disable flag indicates NG, it is determined that connection is not possible.

  Then, when it is determined by this connection possibility determination means that it can be connected to another terminal device 2 via a network, the connection means connects to the other terminal device via the first communication means.

(About router number detection means)
The number-of-routers detection means indicates the number of routers that are passed through when performing communication by wired communication between the other terminal apparatus 2 determined to be connectable by the connection possibility determination means and the own terminal apparatus 2, and the number of pops in the terminal information Detect by referring to.

  Then, when there is a terminal device 2 in which the number of routers detected by the number-of-routers detection unit is less than a predetermined value among the other terminal devices 2 determined to be connectable by the connection determination unit, Terminal device 2 is determined to be close to its own terminal device 2 on the network and connected via the first communication means. When the number of routers is greater than a predetermined value, connection management is performed via the first communication means. The terminal 3 connected to the connection destination candidate notified from the device 3 is connected.

(About communication time detection means)
The communication means detection means detects the communication time between the other terminal apparatus 2 determined to be connectable by the connection possibility determination means and the own terminal apparatus 2 by referring to the RTT of the terminal information.

  Then, when there is a terminal device 2 whose communication time detected by the communication time detection means is less than or equal to a predetermined value among the other terminal devices 2 determined to be connectable by the connection possibility determination means, the connection means When it is determined that the terminal device 2 is close to the terminal device 2 on the network and is connected via the first communication means, and the communication time is greater than a predetermined value, the connection management device via the first communication means 3. Connect to the connection destination candidate notified from 3.

(Display control means)
The display control means has a function of controlling the video chip 211 and the built-in display 212 to display content data and various information. That is, the display control means can control how the content video and various types of information are displayed on the built-in display 212.

  Further, here, as the terminal device 2 of the present embodiment, channel selection means, first communication means, second communication means, connection means, first reception means, second reception means, adjacent terminal information acquisition means, determination means, A terminal device 2 in which various units such as a playback unit, a relay unit, an average playback time detection unit, a NAT table setting unit, a connection availability determination unit, a router number detection unit, and a communication time detection unit are housed in one unit will be described as an example. However, the present invention is not limited to this, and the functions of the various means described above can be divided and stored in a plurality of units according to the usage mode of the terminal device 2.

(Modification of terminal device)
Here, as a modified example of the terminal device 2, third communication means for performing wireless communication between the first communication means, the connection means, the first reception means, the relay means, and the second unit described later. Are stored in at least the first unit,
The second communication means, the channel selection means, the adjacent terminal information acquisition means, the determination means, the reproduction means, and the third communication means for performing wireless communication with the first unit are at least the second unit. The accommodated terminal device 2 will be described.

  As shown in FIG. 10, the terminal device 2 includes a stream relay control module 500 as a first unit and a user interface module 513 as a second unit.

  The stream relay control module 500 is connected to a network such as the Internet by wire communication, and content is transmitted from a device on the upstream side of the distribution path such as another terminal device 2 or the content distribution device 1 connected to the network. While receiving and storing the data in a stream, it is responsible for the stream relay function for streaming the content data to other terminal devices 2 that are sequentially connected to the downstream side.

  The user interface module 513 mainly has a function of receiving and reproducing content data received by the stream relay control module 500 by non-communication, and other terminal devices (adjacent to the geographical location). By performing wireless communication with the terminal device 2, the terminal information of the adjacent terminal device 2 is received and managed, and the user can smoothly perform zapping.

(Configuration of stream relay control module)
Hereinafter, the configuration of the stream relay control module 500 will be specifically described with reference to FIG.

  As shown in FIG. 10, the stream relay control module 500 can be applied to a general personal computer or a dedicated terminal, and has a first CPU (Central Processing Unit) 502 and a rewritable second memory that stores (stores) various programs and the like. A network that functions as a first communication unit for performing communication by wired communication between the main storage device 504 and the content distribution device 1, the connection management device 3, and another terminal device 2 on the network via the Internet 4. The various components are connected to each other via a first system bus 501.

  Also, transmission of content data to the user interface module 513 is performed on the first system bus 501 of the stream relay control module 500 by transmitting and receiving radio signals between the stream relay control module 500 and the user interface module 513. A wireless communication interface 505 that functions as a third communication unit for receiving various control signals from the user interface module 513 is connected to the wireless communication interface 505, and an antenna 506 that transmits and receives wireless signals is connected to the wireless communication interface 505. It is connected.

  In this stream relay control module 500, the wireless communication interface 505 and the network interface 503 constitute communication means.

  In the present embodiment, the first CPU 502 and the first main storage device 504 constitute a first control unit 560. The network interface 503 is connected to the Internet 4 via the router 507. This router 507 corresponds to the router 10 shown in FIG.

(About the first main memory)
Further, the first main storage device 504 is relayed from the content distribution device 1 directly or to another terminal device 2 and the OS program 510 for providing the basic functions of the stream relay control module 500 as a computer. Stream control program 509 for receiving streamed content data and streaming transmission to downstream terminal device 2 and location information (IP address) of terminal device 2 (or content distribution device 1) upstream of the tree connection And the topology control program 511 for managing the location information of the terminal device 2 further downstream connected to the tree, and these are read by the first CPU 502, and these are read by the first CPU 502. Function according to program is executed That.

  In addition, the first main storage device 504 sequentially stores the content data received by streaming, content data that has been transferred to the user interface module 513 among the stored content data, and other connected downstream data. When the terminal device 2 exists, a ring buffer 508 is provided for sequentially erasing the content data that has been distributed to the terminal device 2.

  Here, the OS program 510 is read and executed by the first CPU 502, so that the basic functions of the computer that is the stream relay control module 500 such as memory management of the first main storage device 504 and the like can be executed. To do. Then, with the OS program 510 being executed by the first CPU 502, the above-described stream control program 509, topology control program 511, and the like are read from the first main storage device 504 and executed.

  Note that the OS program 510, the stream control program 509, the topology control program 511, and the like may be downloaded to the main storage device 207 from, for example, a server connected to the Internet 4, or a CD-ROM or the like. After being recorded on the storage medium, it may be read into the first main storage device 504 via the drive of the storage medium.

(About the first controller)
The first control unit 560 includes the first CPU 502 and the first main storage device 504 as described above, and the first CPU 502 reads and executes various programs 509 to 511 stored in the first main storage device 504. The overall stream relay control module 500 is controlled in an integrated manner, and functions in the same manner as the connection means, first reception means, and relay means of the terminal device 2 shown in FIG.

(User interface module configuration)
As shown in FIG. 10, the user interface module 513 can be a general personal computer or a dedicated terminal, and stores (stores) a second CPU (Central Processing Unit) 515, various programs, and the like, as shown in FIG. ) A rewritable second main storage device 519, a hard disk device 516 for storing various data, etc., and a user input remote controller 522 for transmitting and receiving a predetermined infrared signal for the user to remotely operate the user interface module 513. An infrared port 512 for communicating with the user input remote controller 522 by infrared, a peripheral device control chip 520 for controlling the infrared port 512, and image data from the second CPU 515, and receiving an internal video memory (not shown). ) A video chip 523 that displays data written in the video memory on a later-described built-in display 524, a built-in display 524 that performs display in accordance with a signal transmitted from the video chip 523, an FM sound source (Frequency Modulation), and a Wave Table sound source And a built-in speaker 526 that converts an audio signal output from the sound source chip 525 into a sound wave. These various components are mutually connected via the second system bus 514. It is connected.

  Also, the second system bus 514 of the user interface module 513 receives content data from the stream relay control module 500 by transmitting and receiving radio signals between the user interface module 513 and the stream relay control module 500. In addition, a wireless communication interface 517 for transmitting various control signals to the stream relay control module 500 is connected, and an antenna 518 for transmitting and receiving wireless signals is connected to the wireless communication interface 517.

  In the user interface module 513, the wireless communication interface 517 constitutes communication means. In the present embodiment, the second CPU 515 and the second main storage device 519 constitute a second control unit 570.

  Here, the remote controller for user input 522 has a channel selection button (not shown) as channel selection means for selecting a channel of the content distribution system S, and the user of the terminal device 2 uses the channel selection button. It can be connected to a desired channel.

(About the second main memory 519)
In addition, the OS program 530 for providing a basic function of the user interface module 513 as a computer and streaming from the content distribution device 1 directly or to another terminal device 2 are streamed to the second main storage device 519. Stream control program 527 for receiving stream data and streaming transmission to downstream terminal device 2, screen control program 531 for controlling built-in display 524, and content data stream received from upstream device Terminal device monitoring that monitors the proximity of the decoder program 532 for decoding and reproduction and the adjacent terminal device 2 and other terminal devices 2 connected by wired communication on the network, terminal information update information, and the like Program 258 etc. Stored and, it is retrieved by the 2CPU515, and functions according to the program by the first 2CPU515 is executed.

  The second main storage device 519 stores terminal device management information 529 for storing and managing terminal information acquired from the plurality of adjacent terminal devices 2.

  Here, the OS program 530 is read and executed by the second CPU 515, thereby enabling users to perform functions related to input / output of the user input remote controller 522, memory management such as the second main storage device 519 and the hard disk device 516. The basic function of the computer which is the interface module 513 is made executable. Then, with the OS program 530 being executed by the second CPU 515, the above-described stream control program 527, screen control program 531, decoder program 532, terminal device monitoring program 528, etc. are read from the second main storage device 514. Executed.

  Note that the OS program 530, the stream control program 527, the screen control program 531, the decoder program 532, the terminal device monitoring program 528, and the like are downloaded to the second main storage device 519 from, for example, a server connected to the Internet 4. Alternatively, it may be recorded on a storage medium such as a CD-ROM and then read into the second main storage device 519 via a drive of the storage medium.

(About the second control unit)
The second control unit 570 includes the second CPU 515 and the second main storage device 519 as described above, and the second CPU 515 reads out various programs 527, 528, and 530 to 532 stored in the second main storage device 519. By executing this, the entire user interface module 513 is controlled in an integrated manner, and the second receiving means, adjacent terminal information obtaining means, determination means, reproduction means, average reproduction time detection means, and NAT table of the terminal device 2 shown in FIG. It functions in the same manner as the setting means, connection possibility determination means, router number detection means, communication time detection means, and the like.

  Thus, the usability of the terminal device 2 can be further improved by dividing the functions of the terminal device 2 into two units according to the usage pattern.

  For example, the stream relay control module 500 can be provided near the installation location of the Internet router, and the user interface module 513 can be provided in the user's room. In this case, the user interface module 513 has reduced its function, Since the terminal device 2 shown in FIG. 9 can be made smaller, the space occupied by the terminal device 2 in the user's room can be reduced as much as possible.

  In addition, since the user interface module 513 can receive and reproduce content data from the stream relay control module 500 by wireless communication, the number of channels used for wireless communication is increased and one stream relay control module 500 is installed. If the user interface module 513 is possessed by a plurality of users, each user can view content data in his / her own room.

[4. Description of Configuration of Connection Management Device 3]
Next, the configuration and operation of the connection management device 3 will be described with reference to FIG.

  FIG. 11 is a diagram illustrating a schematic configuration example of the connection management device 3 in the present embodiment. The connection management device 3 can be a general server computer. As shown in FIG. 11, a CPU (Central Processing Unit) 402, a rewritable main storage device 405 for storing (storing) various programs, and the like, A hard disk device 403 that stores various data, a network interface 404 that communicates with the content distribution device 1 and the terminal device 2 via the Internet 4, a keyboard 407 and a mouse 408 that can input predetermined information Peripheral device control chip 406 that controls the input means, and video chip 409 that receives image data from CPU 402 and writes it to an internal video memory (not shown) and displays the data written to this video memory on display 410 (to be described later). These various components are They are connected to each other via a stem bus 401.

In the present embodiment, the CPU 402 and the main storage device 405 constitute a control unit 430. The network interface 404 is connected to the Internet 4 via the router 418. This router 418 corresponds to the router 10 shown in FIG.
(Regarding main memory 405)
The main storage device 405 also includes an OS program 416 for providing basic functions of the connection management device 3 as a computer, and location information (IP addresses and port numbers) of a plurality of terminal devices 2 connected to the channel. Etc.), a topology management program 414 for constructing and managing a tree-like hierarchical structure of each channel, and a channel corresponding to a connection destination introduction request transmitted from the terminal device 2 A connection destination introduction program 417 for transmitting connection destination candidate information to the terminal device 2, an operation management program 415 for managing the operation of the content distribution system S, and the like are stored. These are read by the CPU 402, and the CPU 402 follows these programs. Function is executed.

  Here, the OS program 416 is read out and executed by the CPU 402, whereby functions related to input / output of the keyboard 407 and mouse 408, and connection management device 3 such as memory management of the main storage device 405 and hard disk device 403. It is possible to execute the basic functions of a computer. Then, with the OS program 416 being executed by the CPU 402, the above-described terminal management program 413, topology management program 414, connection destination introduction program 417, operation management program 415, and the like are executed.

  The OS program 416, the terminal management program 413, the topology management program 414, the connection destination introduction program 417, the operation management program 415, etc. are downloaded to the main storage device 405 from, for example, a server connected to the Internet 4. Alternatively, it may be recorded on a storage medium such as a CD-ROM and then read into the main storage device 405 via a drive of the storage medium.

(About control unit 430)
The control unit 430 is composed of the CPU 402 and the main storage device 405 as described above, and the CPU 402 reads out and executes various programs 413 to 417 stored in the main storage device 405, thereby supervising the entire connection management device 3. It controls and functions as a connection destination candidate selection unit, a notification unit, a topology management unit, a terminal management unit, etc., which will be described later, and further uses the hard disk device 403 as a connection state information storage unit.

  It should be noted that the CPU 402 executes the terminal management program 413 as a terminal management unit or the like, and the CPU 402 executes the topology management program 414 as a topology management unit or the like, and further the CPU 402 executes the connection destination introduction program 417. Respectively function as connection destination candidate selection means, notification means, etc., and in this embodiment, the connection destination candidate selection means and notification means constitute the connection destination candidate notification means.

(About terminal management means)
When receiving the registration request from the terminal device 2, the terminal management means registers the IP address, which is the location information of the terminal device 2, in the terminal management database 412 for each channel. Also, when a registration request is received from the content distribution apparatus 1, the IP address, which is the location information of the content distribution apparatus 1, is registered in the terminal management database 412 for each channel. The location information of the terminal device 2 is included in the registration request from the terminal device 2, and the location information is acquired from the registration request.

(About topology management means)
The topology management means includes a new topology generation means for generating a tree-like hierarchical structure of a new channel based on a new channel generation request transmitted from the content distribution apparatus 1, and a connection destination introduction request or connection disconnection of the terminal device 2. It has a function as topology change means for changing connection information of the terminal device 2 in the channel by topology change notification such as notification. Further, the topology management means stores the connection status information of the terminal device 2 constituting the hierarchical structure for each channel in the topology database 411 as the connection status information storage means.

  When receiving a new channel generation request from the content distribution apparatus 1, the new topology generation unit generates a new channel topology table and registers it in the topology database 411. Here, the topology table is a table for storing connection state information and the like of the terminal device 2 constituting a hierarchical structure for each channel, and is generated for each channel and registered in the topology database 411.

  The topology change means executes a function of adding or deleting information of the terminal device 2 to / from a plurality of topology tables stored in the topology database 411. Based on the connection destination introduction request topology participation report from the terminal device 2 Addition or change to the topology table.

(About connection destination candidate selection means)
When receiving the connection destination introduction request from the terminal device 2 that is about to newly join the channel, the connection destination candidate selecting means, in the hierarchical structure of the channel corresponding to the connection destination introduction request, the terminal device 2 constituting the hierarchical structure. The connection destination candidate for the connection destination introduction request is selected from the connection state information stored in the topology database 411.

(Notification means)
The notifying unit has a function of notifying the connection destination candidate selected by the connection destination candidate selecting unit to the terminal device 2 that has transmitted the connection destination introduction request. The notification of the connection destination candidate includes information on the connection destination candidate, that is, information such as the communication protocol, IP address, and port number of the connection destination candidate terminal device 2.
[5. Operation of content distribution system S]
Hereinafter, detailed operations of the terminal device 2 and the connection management device 3 will be described more specifically with reference to flowcharts.

(Description of processing flow of terminal device 2)
First, a more specific operation of the terminal device 2 will be described with reference to FIGS. 12 is a flowchart showing the overall processing in the terminal device 2, FIG. 13 is a flowchart showing channel switching processing in the terminal device 2, FIG. 14 is a flowchart showing connection change processing in the terminal device 2, and FIG. FIG. 16 is a flowchart showing a connection establishment process in the terminal device 2, and FIG. 17 is a flowchart showing a content data transmission start / stop process in the terminal device 2.

  First, with reference to FIG. 12, the outline of the entire processing in the terminal device 2 will be described.

  First, when the terminal device 2 is powered on, the terminal device 2 initializes the programs 216 to 222 (step S101). The programs 216 to 222 are executed by the CPU 202, and the control unit 230 After operating the function, the process proceeds to step S102.

  In step S <b> 102, the control unit 230 determines whether or not a channel switching request has been made by a user operation 210. If it is determined in step S102 that a channel switching request has been made (step S102: YES), the control unit 230 performs a channel switching process shown in FIG. 13 in step S103.

  If it is determined in step S102 that a channel switching request has not been made (step S102: NO), the control unit 230 determines whether an upstream terminal candidate has been received from the connection management device 3 (step S102). S105).

  That is, the control unit 230 determines whether or not a candidate for another terminal device 2 that can be connected to the upstream side of the terminal device 2 has been received in the hierarchical structure selected by the user from the connection management device 3.

  In step S105, when it is determined that the upstream terminal candidate has been received (step S105: YES), the control unit 230 performs the connection process illustrated in FIG. 14 in step S106.

  In step S105, if the control unit 230 determines that an upstream terminal candidate has not been received (step S105: NO), the process proceeds to step S107.

  In step S <b> 107, the control unit 230 determines whether or not a status report notification has been received from the adjacent terminal device 2. That is, the control unit 230 determines, from another terminal device 2 installed in a geographically close location to the own terminal device 2, the device number, location information, connected channel, downstream connection availability regarding the other terminal device 2. It is determined whether terminal information such as the number of pops and RTT has been received.

  In step S107, when it is determined that the status report notification has been received (step 107: YES), the control unit 230 performs pre-connection processing shown in FIG. 15 in step S108 and determines that the status report notification has not been received. If so (step S107: NO), the process proceeds to step S109.

  In step S109, the control unit 230 determines whether or not a content data packet has been received from the upstream terminal device 2. That is, the control unit 230 determines whether or not content data is being received from the terminal device connected to the resident terminal device 2 in a hierarchical structure.

  In step S109, when the control unit 230 determines that the content data packet has been received from the upstream terminal device 2 (step S109: YES), the control unit 230 moves the process to step S110 and transfers the packet to the downstream terminal device 2. .

  That is, here, the control unit 230 divides content data received from another terminal device 2 connected to the upstream side of the hierarchical structure into a plurality of content data packets, and connects to the downstream side of the hierarchical structure. It relays and distributes to the other terminal device 2, Then, a process is moved to step S111.

  In step S111, the control unit 230 acquires the packet that has reached the playback time from the ring buffer 215 and plays it. That is, here, the control unit 230 refers to the reproduction time information included in the plurality of content packets received from the other terminal devices 2 connected to the upstream side in the hierarchical structure and sequentially stored in the ring buffer 215, and The content packets that have reached the playback time are sequentially decoded and sequentially played back.

  If the control unit 230 determines in step S109 that no content data packet has been received from the upstream terminal device 2 (step S109: NO), the process proceeds to step S112.

  In step S112, the control unit 230 determines whether or not a content data packet has been received from the adjacent terminal device 2. That is, here, the control unit 230 determines whether or not content data divided into a plurality of packets by wireless communication is received from the adjacent terminal device 2 via the wireless communication interface 204.

  In step S112, when the control unit 230 determines that the content data packet has been received from the adjacent terminal device 2 (step S112: YES), the control unit 230 moves the process to step S113, and performs the connection establishment process illustrated in FIG.

  In step S112, when the control unit 230 determines that a content data packet has not been received from the adjacent terminal device 2 (step S112: NO), the process proceeds to step S114.

  In step S114, the control unit 230 determines whether or not there is a stream transmission start / stop request. That is, here, the control unit 230 receives either one of the request for starting transmission of the content data stream and the request for stopping transmission of the content data from the other terminal device 2 via the wireless communication interface 204 or the network interface 206. Judge whether or not.

  In step S114, when it is determined that there is a stream transmission start / stop request (step S114: YES), the control unit 230 moves the process to step S115 and performs the content data transmission start / stop process shown in FIG.

  In step S114, when the control unit 230 determines that there is no stream transmission start / stop request (step S114: NO), the process proceeds to step S116.

  In step S <b> 116, the control unit 230 determines whether or not it is a status report opportunity to the adjacent terminal device 2. That is, here, the control unit 230 determines whether or not a predetermined period (here, 1 minute) has elapsed since the terminal information of the terminal device 2 was transmitted to the plurality of adjacent terminal devices 2 last time. It is determined whether it is a status report trigger.

  When it is determined in step S116 that the control unit 230 is a state report opportunity, that is, when it is determined that a predetermined period has elapsed since the terminal information of the terminal device 2 was transmitted to the plurality of adjacent terminal devices 2 last time. In (Step S116: YES), the process proceeds to Step S117, and the terminal information of the current terminal device 2 at the current time is transmitted to a plurality of adjacent terminal devices 2 simultaneously via the wireless communication interface 204.

  In step S116, the control unit 230 moves the process to step S104 when it is determined that it is not a status report opportunity and when the processes of steps S103, S106, 108, S111, S113, S115, and S117 are completed.

  In step S104, the control unit 230 determines whether or not the power of the terminal device 2 has been turned off by the user's operation. When it is determined that the terminal device 2 has been turned off (S104: YES), all the processes are terminated and turned off. If it is determined that there is not (step S104: NO), the process returns to step S102.

(Channel switching process)
Next, the channel switching process performed in S103 shown in FIG. 12 will be specifically described with reference to FIG.

  In the channel switching process, the control unit 230 first makes a content stream stop request to the current content data supply source terminal device 2 (step S118).

  That is, here, the control unit 230 sends the content data of the channel selected by the previous operation of the user input remote controller 210 to the other terminal device 2 that is currently transmitting the stream to the terminal device 2 itself. Then, a process for requesting the transmission stop is performed, and then the process proceeds to step S119.

  In step S119, the control unit 230 determines whether there is an adjacent terminal device 2 that is viewing the requested channel. That is, here, the control unit 230 refers to the connected channel of the terminal information, so that the connected channel number is the same as the channel number selected by the user's operation of the user input remote control 210 this time. It is determined whether or not the device 2 exists.

  In step S119, when the control unit 230 determines that there is an adjacent terminal device that is viewing the requested channel (step S119: YES), the control unit 230 moves the process to step S120 and connects the connected channel via the wireless communication interface 204. The processing for requesting the stream distribution of the content data to the adjacent terminal device 2 whose channel number is the same as the channel number selected by the user is performed, and then this channel switching processing is terminated and the processing is shown in step S104 in FIG. Move to.

  In step 119, when the control unit 230 determines that there is no adjacent terminal device that is viewing the requested channel (step S 119: NO), the control unit 230 requests an upstream terminal candidate from the connection management device 3. The channel switching process is terminated, and the process proceeds to step S104 shown in FIG.

(Connection process)
Next, the connection process performed in S106 shown in FIG. 12 will be specifically described with reference to FIG.

  In the connection process, the control unit 230 first selects one upstream terminal device 2 from the acquired candidates (step S122). That is, here, the control unit 230 selects one terminal device 2 from among a plurality of other terminal device 2 candidates (upstream terminal devices 2) connected to the upstream side of the terminal device 2 notified from the connection management device 3. A process of arbitrary selection is performed, and then the process proceeds to step S123.

  In step S123, the control unit 230 performs NAT traversal processing on the upstream terminal device 2. That is, the control unit 230 enables the local terminal device 2 to transmit an IP packet to the upstream terminal device 2 from the outside of the router 10 to which the upstream terminal device 2 selected in the process of step S122 is connected. In order to enable the upstream terminal device 2 to transmit an IP packet to the local terminal device 2 from the outside of the router 10 to which the local terminal device 2 is connected, the IP packet is transmitted to the upstream terminal device 2 at the same time. An IP packet transmitted from the upstream terminal device 2 to the own terminal device 2 is received.

  At this time, the control unit 230 sets the NAT table of the NAT router using the IP packet received from the upstream terminal device 2, and then moves the process to step S124.

  In step S124, the control unit 230 determines whether or not the upstream terminal device 2 is close to the network. That is, here, the control unit 230 refers to the number of pops of the terminal information and the RTT, thereby measuring the proximity of the terminal device 2 and the upstream terminal device 2 on the network, and based on the measurement result, It is determined whether the terminal device 2 and the terminal device 2 are close to each other in terms of network.

  At this time, the control unit 230 obtains the number of routers existing on the network between the terminal device 2 and the upstream terminal device 2 from the pop number, and the number of routers is equal to or less than a predetermined value, and When the communication time between the terminal device 2 and the upstream terminal device 2 is acquired from the RTT and the communication time is equal to or less than a predetermined value, the upstream terminal device 2 and the terminal device 2 Judge that it is close to the network.

  On the other hand, when the acquired number of routers is greater than a predetermined value, or when the control unit 230 determines that the acquired communication time is longer than the predetermined value, the control unit 230 and the own terminal device 2 Is determined to be far from the network.

  In step S124, when the control unit 230 determines that the upstream terminal device 2 and the own terminal device 2 are far from each other on the network (step S124: NO), the control unit 230 returns the process to step S122, and the own terminal on the network. Until the other upstream terminal device 2 close to the device 2 is detected, the processes in steps S122 to S124 are repeated.

  In step S124, when the control unit 230 determines that the upstream terminal device 2 and the terminal device 2 are close to each other in a network (step S124: YES), the control unit 230 connects as the downstream terminal device of the upstream terminal device 2, and then The process proceeds to step S125.

  In step S125, the control unit 230 is connected as a downstream terminal of the upstream terminal device 2, and then the process proceeds to step S126.

  In step S126, the control unit 230 transmits a topology participation report to the connection management device 3 via the network interface 206, and then moves the process to step S104 shown in FIG.

(Pre-connection process)
Next, the pre-connection process performed in S108 shown in FIG. 12 will be specifically described with reference to FIG.

  In the pre-connection process, the control unit 230 first registers the received information in the terminal information (step S127). That is, here, the control unit 230 acquires the device number, location information, connected channel, downstream connection availability, pop count, and RTT of each adjacent terminal device 2 as terminal information from each status report notification received in step S107. Thus, the already acquired state information is updated and registered, and then the process proceeds to step S128.

  In step S128, the control unit 230 acquires, from the terminal information registered in step S127, the number of pops and the RTT of the adjacent terminal device 2 that has transmitted the terminal information, and uses the number of pops and the RTT to determine the adjacent number. The network proximity to the terminal device 2 is measured, and then the process proceeds to step S129.

  In step S129, the control unit 230 determines whether or not there is an adjacent terminal device 2 that should exceed the NAT based on the result of measuring the proximity in the network in step S128.

  That is, in this step S129, when the control unit 230 determines that there is no adjacent terminal apparatus 2 whose proximity measured in the network measured in S128 is higher than a predetermined value (step S129: NO), this pre-connection process Is finished, the process proceeds to step S104 shown in FIG. 12, and if it is determined that there is an adjacent terminal device 2 whose proximity is higher than a predetermined value (step S129: YES), the process proceeds to step S130. Note that the same determination criterion as the determination criterion in the process of step S124 in FIG. 14 is used as the determination criterion in step S129.

  In step S130, the control unit 230 performs a NAT traversal process on the adjacent terminal device 2 determined to be traversed in NAT in step S129 in the same manner as in step S123 shown in FIG. The process ends and the process moves to step S104 shown in FIG.

(Connection establishment process)
Next, the connection establishment process performed in S113 shown in FIG. 12 will be specifically described with reference to FIG.

  In the connection establishment process, the control unit 230 first decodes the content data divided into a plurality of packets received from the end device 2 connected upstream in the hierarchical structure in step S131, and immediately reproduces it. To step S132.

  In step S132, the control unit 230 determines whether or not a certain period of time has elapsed since the start of packet reception by wireless communication in step S112, and determines that the certain period of time has elapsed (step S132: YES). The process proceeds to step S133, and if it is determined that the predetermined time has not elapsed (step S132: NO), this connection establishment process is terminated, and the process proceeds to step S104 shown in FIG.

  In step S133, the control unit 230 refers to the terminal information of the adjacent terminal device 2 that has continuously transmitted the packet by wireless communication for a certain period of time, and then moves the process to step S134.

  In step S134, the control unit 230 determines whether or not the adjacent terminal device 2 is close to the network based on the terminal information referred to in step S133, and determines that the adjacent terminal device 2 is close to the network (step S134: YES). ), The process moves to step S135. If it is determined that the network is far (step S134: NO), the process moves to step S137. Note that the determination criteria here are the same as the determination criteria in the process of step S124 of FIG.

  In step S135, the control unit 230 performs processing to connect as a downstream terminal device to the downstream side of the adjacent terminal device 2 determined to be close to the own terminal device 2 in step S134 (step S135), and then connected. A request for transmission of the content stream is made to the upstream adjacent terminal device 2 (step S136), the connection establishment process is terminated, and the process proceeds to step S104 shown in FIG.

  In step S137, the control unit 230 sends the upstream terminal to the connection management apparatus 3 in order to notify a connection destination candidate different from the adjacent terminal apparatus 2 that is determined to be network-distant from the terminal apparatus 2 in step S134. The device candidate is requested, and then the connection establishment process is terminated, and the process proceeds to step S104 shown in FIG.

(Content data transmission start / stop processing)
Next, the content data transmission start / stop process performed in step S115 shown in FIG. 12 will be specifically described with reference to FIG.

  In the content data transmission start / stop processing, the control unit 230 first determines whether or not the request received in step S114 is a request via the wireless communication interface 204 (step S138). If it is determined that the request is made (step S138: YES), the process proceeds to step S139, and if the request is not made via the wireless communication interface 204, that is, if the request is made via the network interface 206 (step S138). : NO), the process proceeds to step S140.

  In step S139, the control unit 230 starts transmission of content data or stops transmission of content data to the adjacent terminal device 2 that has transmitted the request received via the wireless communication interface 204 in response to the request.

  In step S <b> 140, the control unit 230 starts transmission of content data or stops transmission of content data to another terminal device 2 that has transmitted the request received via the network interface 206 in response to the request.

(Description of processing flow of connection management device 3)
Next, a more specific operation of the connection management device 3 will be described with reference to FIG. FIG. 18 is a flowchart showing the entire processing in the connection management device 3.

  When the power of the connection management device 3 is turned on, the connection management device 3 initializes the programs 413 to 417, puts the programs 413 to 417 into an execution state by the CPU 402, and operates the function as the control unit 430 ( Step S201).

  First, the control unit 430 determines whether or not a request to join a channel is received from the terminal device 2 (step S202).

  If it is determined in step S202 that a request for participation in the channel has been received from the terminal device 2 (step S202: YES), the control unit 430 transmits the location information of the terminal device 2 included in the received participation request to the terminal management database 412. Register (step S203).

  On the other hand, if it is determined in step S202 that a request to join the channel has not been received from the terminal device 2 (step S202: NO), the control unit 430 determines whether or not a registration request from the content distribution device 1 has been received. Determination is made (step S205).

  If it is determined in step S205 that the registration request from the content distribution device 1 has been received (step S205: YES), the control unit 430 sends the location information of the content distribution device 1 included in the received registration request to the terminal management database 412. Registration is performed (step S206).

  Next, the control unit 430 registers information on the new channel in the topology database 411. That is, a topology table for a new channel is generated in the topology database 411 (step S207).

  If it is determined in step S205 that the registration request from the content distribution apparatus 1 has not been received (step S205: NO), the control unit 430 determines whether a connection destination introduction request has been received from the terminal apparatus 2 (step S205: NO). Step S208).

  If it is determined in step S208 that a connection destination introduction request has been received from the terminal device 2 (step S208: YES), the control unit 430 selects a terminal device 2 that is a connection destination candidate from the topology database 411 (step S209).

  The control unit 430 of the connection management device 3 sends back and notifies the connection destination candidates selected in this way to the terminal device 2 that has made the connection destination introduction request (step S210).

  If it is determined in step S208 that a connection destination introduction request has not been received from the terminal device 2 (step S208: NO), the control unit 430 determines whether a topology participation report has been received from the terminal device 2 (step S211). .

  If it is determined in step S211 that there has been a topology participation report from the terminal device 2 (step S211: YES), the control unit 430 extracts location information of the terminal device included in the topology participation report, and updates the topology database 411. This is performed (step S212). That is, the control unit 430 registers the topology change in the topology database 411.

  When it is determined in step S211 that there is no topology participation report from the terminal device 2 (step S211: NO), and when the processing of steps S203, S207, S210, and S212 is completed, the control unit 430 It is determined whether or not a service termination operation has been performed (step S204). If it is determined that the service end operation has not been performed (step S204: NO), the process returns to step S202. If it is determined that the service end operation of the connection management device 3 has been performed (step S204: YES), the process is performed. finish.

(Embodiment of wireless communication)
In the present invention, a communication method using a wireless LAN is exemplified as the second communication means (wireless communication means) with a nearby terminal device, but any method may be used as long as wireless communication is possible. For example, a communication method such as WiMAX (Worldwide Interoperability for Microwave Access) having a communication range wider than that of the wireless LAN may be selected.

  As described above, some of the embodiments of the present invention have been described in detail with reference to the drawings. However, these are merely examples, and the knowledge of those skilled in the art including the aspects described in the above [Disclosure of the Invention] section. It is possible to implement the present invention in other forms in which various modifications and improvements are made based on the above.

It is a figure showing an example of outline composition of contents distribution system S concerning this embodiment. It is explanatory drawing which shows the communication form by the wire communication of each terminal device 2 in this embodiment, and radio | wireless communication. 4 is an explanatory diagram illustrating an example of adjacent terminal information stored in a terminal device 2. FIG. It is explanatory drawing which shows the hierarchical structure where the content data of 1 channel are delivered by streaming, and the hierarchical structure where the content data of 2 channels are delivered by streaming. It is explanatory drawing which looked at zapping in the flow of time. It is explanatory drawing which looked at zapping in the flow of time. It is explanatory drawing which looked at zapping in the flow of time. It is a functional block diagram which shows a content delivery apparatus. It is a functional block diagram which shows a terminal device. It is a functional block diagram which shows the modification of a terminal device. It is a functional block diagram which shows a connection management apparatus. It is a flowchart which shows the process which the control part of a terminal device performs. It is a flowchart which shows the process which the control part of a terminal device performs. It is a flowchart which shows the process which the control part of a terminal device performs. It is a flowchart which shows the process which the control part of a terminal device performs. It is a flowchart which shows the process which the control part of a terminal device performs. It is a flowchart which shows the process which the control part of a terminal device performs. It is a flowchart which shows the process which the control part of a connection management apparatus performs.

Explanation of symbols

S Content Distribution System 1 Content Distribution Device 2 Terminal Device 3 Connection Management Device 230 Control Unit 202 CPU
207 Main storage device 204 Wireless communication interface 206 Network interface 233 Router

Claims (13)

One or more content distribution apparatuses for streaming distribution of content data via a network through a plurality of channels, a plurality of terminal apparatuses for receiving and reproducing the content data via the network, and the content distribution apparatus for each channel And a connection management device for managing the plurality of terminal devices so as to be logically connected in a multi-layered hierarchical structure on the network, and the content data streamed from the content distribution device for each channel In the content data distribution system that relays to the downstream of the hierarchical structure sequentially by the relay function of the terminal device,
The content distribution device includes:
A delivery means for streaming the content data;
The connection management device includes:
Connection state information storage means for storing connection state information of the terminal device constituting the hierarchical structure for each channel;
When a connection destination introduction request is received from the terminal device, a connection destination candidate is selected from the connection state information stored in the connection state information storage unit, and the connection destination candidate is transmitted to the connection destination introduction request. Connection destination candidate notification means for notifying the terminal device,
The terminal device
Channel selection means for selecting the channel;
The first communication means for communicating with the distribution device, the connection management device, and the other terminal device on the network, and the other terminal device that is adjacent on a different route from the network by transmitting / receiving a radio signal Communication means having second communication means for communicating with;
Via the first communication means, the connection destination introduction request for the channel selected by the channel selection means is transmitted to the connection management device, and then connected to the connection destination candidate notified from the connection management device. Connection means;
First receiving means for receiving content data from the connected connection destination candidates via the first communication means;
Via the second communication means, adjacent terminal information acquisition means for acquiring terminal information including a channel number selected by the other adjacent terminal device;
A determination unit that determines whether the channel number acquired by the adjacent terminal information acquisition unit matches the channel number selected by the channel selection unit when the channel is selected by the channel selection unit;
When the determination unit determines that the channel numbers match, the second terminal unit requests streaming delivery of content data of the channel selected by the channel selection unit to the other terminal device, and Second receiving means for receiving the content data from another terminal device;
Reproduction means for reproducing the content data received by the second reception means after the channel selection means has selected the channel and before reproducing the content data received by the first reception means;
Relay for receiving the content data relay request from the other terminal device via the first communication means and transferring the content data received via the first communication means to the terminal device that has made the relay request And a content data distribution system. One or more content distribution apparatuses for streaming distribution of content data via a network through a plurality of channels, a plurality of terminal apparatuses for receiving and reproducing the content data via the network, and the content distribution apparatus for each channel And a connection management device for managing the plurality of terminal devices so as to be logically connected in a multi-layered hierarchical structure on the network, and the content data streamed from the content distribution device for each channel In the content data distribution method in the content data distribution system that sequentially relays downstream of the hierarchical structure by the relay function of the terminal device,
The content distribution device includes:
Streaming delivery of the content data,
The connection management device includes:
Storing connection state information of the terminal device constituting the hierarchical structure for each channel in a connection state information storage unit;
When a connection destination introduction request is received from the terminal device, a connection destination candidate is selected from the connection state information stored in the connection state information storage unit, and the connection destination candidate is transmitted to the connection destination introduction request. And notifying the terminal device,
The terminal device
Detecting the selection of the channel;
Via the first communication means for communicating with the distribution device on the network, the connection management device, and the other terminal device, the connection destination introduction request for the channel selected by the channel selection means is the connection management. Transmitting to a device, and then connecting to the connection destination candidate notified from the connection management device;
Receiving the content data from the connected candidate for connection via the first communication means;
Obtaining terminal information including a channel number selected by the other adjacent terminal device via a second communication means for communicating by transmitting and receiving a radio signal through a route different from the network;
Determining whether the acquired channel number matches the selected channel number when the channel is selected;
When it is determined that the channel numbers match, the other terminal device is requested to stream the content data of the selected channel via the second communication means, and the content data is transmitted from the other terminal device. Receiving the step,
Replaying the content data received from the other terminal device until the content data received from the connection destination candidate is replayed after the channel is selected;
Receiving the relay request for the content data from the other terminal device via the first communication means, and transferring the content data received via the first communication means to the terminal device that has made the relay request And a content data delivery method characterized by comprising: One or more content distribution apparatuses for streaming distribution of content data via a network through a plurality of channels, a plurality of terminal apparatuses for receiving and reproducing the content data via the network, and the content distribution apparatus for each channel And a connection management device for managing the plurality of terminal devices so as to be logically connected in a multi-layered hierarchical structure on the network, and the content data streamed from the content distribution device for each channel In the terminal device in the content data distribution system that sequentially relays downstream of the hierarchical structure by the relay function of the terminal device,
Channel selection means for selecting the channel;
The first communication means for communicating with the distribution device, the connection management device, and the other terminal device on the network, and the other terminal device that is adjacent on a different route from the network by transmitting / receiving a radio signal Communication means having second communication means for communicating with;
A connection for transmitting the connection destination introduction request regarding the channel selected by the channel selection unit to the connection management device via the first communication unit, and then connecting to the connection destination candidate notified from the connection management device Means,
First receiving means for receiving content data from the connected connection destination candidates via the first communication means;
Via the second communication means, adjacent terminal information acquisition means for acquiring terminal information including a channel number selected by the other adjacent terminal device;
A determination unit that determines whether the channel number acquired by the adjacent terminal information acquisition unit matches the channel number selected by the channel selection unit when the channel is selected by the channel selection unit;
When the determination unit determines that the channel numbers match, the second terminal unit requests streaming delivery of content data of the channel selected by the channel selection unit to the other terminal device, and Second receiving means for receiving the content data from another terminal device;
Reproduction means for reproducing the content data received by the second reception means after the channel selection means has selected the channel and before reproducing the content data received by the first reception means;
Relay for receiving the content data relay request from the other terminal device via the first communication means and transferring the content data received via the first communication means to the terminal device that has made the relay request And a terminal device. The connection means of the terminal device is:
4. The terminal according to claim 3, wherein when the channel number is determined to match by the determination unit, the channel selection unit waits for a predetermined period after the channel is selected and connects to the connection destination candidate. apparatus. The terminal device
An average playback time detecting means for detecting an average playback period by the playback means for the content data for each channel;
The terminal device connection means comprises:
The terminal apparatus according to claim 4, wherein the terminal apparatus is connected to the connection destination candidate using the average reproduction period as the predetermined period. The connection means of the terminal device is:
When the adjacent terminal information acquisition unit cannot acquire the terminal information or when the determination unit determines that the channel numbers do not match, the channel selection unit waits for the predetermined period after the channel is selected. The terminal device according to claim 4, wherein the terminal device is connected to the connection destination candidate without connecting. The connection means of the terminal device is:
When another channel is selected by the channel selection unit within the predetermined period after the channel selection unit selects the channel, the channel is not connected to the connection destination candidate. The terminal device according to any one of claims 4 to 6. The terminal device
When it is determined from the terminal information acquired by the adjacent terminal information acquisition unit of the terminal device that the other terminal device is connected to a NAT (network address replacement) router, the other unit is connected before the connection operation by the connection unit. 8. A NAT table setting means for setting a NAT (network address replacement) table of the NAT router, which is necessary for establishing a communication connection between the terminal device and the own terminal device. The terminal device according to any one of claims. The terminal information includes information on whether or not it can be connected to the other terminal device via the network,
The terminal device
Based on the terminal information acquired by the adjacent terminal information acquisition unit, it is determined whether or not the second terminal unit receiving the content data can be connected to the other terminal device via the network. A connection possibility determination means for
The connection means of the terminal device is:
The connection to the other terminal device is determined by the connection possibility determination unit, and the connection is made to the other terminal device via the first communication unit. The terminal device according to item 1. Router number detection means for detecting the number of routers between the other terminal device and the terminal device determined to be connectable by the connection possibility determination unit;
The connection means of the terminal device is:
Among the other terminal devices that are determined to be connectable by the connectability determination unit, when there is a terminal device in which the number of routers detected by the router number detection unit is a predetermined value or less, the other terminal device includes the 10. The terminal device according to claim 9, wherein the terminal device is connected through the first communication unit, and is connected to the connection destination candidate through the first communication unit when the number of routers is larger than a predetermined value. A communication time detecting means for detecting a communication time between the other terminal apparatus determined to be connectable by the connection possibility determining means and the terminal apparatus;
The connection means of the terminal device is:
When there is a terminal device whose communication time detected by the communication time detection unit is less than or equal to a predetermined value among the other terminal devices determined to be connectable by the connection possibility determination unit, the terminal device includes the first terminal The terminal device according to claim 9, wherein the terminal device is connected via a communication unit, and is connected to the connection destination candidate via the first communication unit when the communication time is greater than a predetermined value. Storing the second communication means, the channel selection means, the neighboring terminal information acquisition means, the determination means, and the reproduction means in at least the first unit;
The first communication means, the connection means, the first reception means, the relay means, and the third communication means for performing wireless communication with the first unit are accommodated in at least the second unit,
The terminal device according to any one of claims 4 to 10, wherein the second communication unit is configured to be capable of wireless communication with the third communication unit.   The program for making a computer function as each means of the terminal device of any one of Claims 4-12.

Images