WO2007145078A1

WO2007145078A1 - Content delivery system, content delivery method, terminal device and recording medium with its program recorded therein

Info

Publication number: WO2007145078A1
Application number: PCT/JP2007/061048
Authority: WO
Inventors: Tomohiro Suzuki
Original assignee: Brother Kogyo Kabushiki Kaisha
Priority date: 2006-06-16
Filing date: 2007-05-31
Publication date: 2007-12-21
Also published as: JP2007336396A

Abstract

In a content delivery system for a user to view and buy contents, a content delivery system, a method, etc. are provided to reduce a load imposed on a content delivery device or a network. The content delivery system is comprised of a first delivery configuration for streaming contents data from a content delivery device (1) to a terminal device (2) in a broadcast configuration, and a second delivery configuration in which one terminal device (2) holding contents data among a plurality of the terminal devices (2) delivers them in response to a request from another terminal device (2) to download the contents data. Then, the content delivery system is set up as a user of the terminal device (2) views contents data broadcasted from the content delivery device (1) by the first delivery configuration, and can download the contents data sent from the content delivery device (1) by the second delivery configuration from the other terminal device.

Description

Specification

CONTENT DISTRIBUTION SYSTEM, CONTENT DISTRIBUTION METHOD, TERMINAL DEVICE, AND RECORDING MEDIUM CONTAINING THE PROGRAM

Technical field

TECHNICAL FIELD [0001] The present invention relates to a technical field of content distribution via a network, and more specifically, a content distribution system, a content distribution method, a terminal device, and a program thereof for a user to purchase content while viewing the content. The present invention relates to a recorded recording medium. Background art

[0002] In recent years, with the spread of broadband and DMP (Digital 'Media Player'), content data such as music and movies (hereinafter also referred to as “content”) can be easily accessed via networks such as the Internet. It has come to be able to purchase. For example, VOD (video on demand) and online content purchase services are popular.

[0003] In content purchase services that receive content distribution via a network, a list of contents that can be purchased is transmitted to the user's terminal device, and the user downloads the desired content based on the list. General power Recently, there is something that allows users to view content that can be purchased.

[0004] As a method for a user to purchase content while viewing the content, a method using a server client type distribution form is common. That is, the content distribution device that is the server Streams and plays the content data to be streamed on the user's terminal device, the user views it, and if the user likes it, the content data is transferred from the content distribution device to the terminal. This is a distribution form downloaded to the device (for example, see Patent Document 1).

Patent Document 1: JP 2003-263175 A

Disclosure of the invention

Problems to be solved by the invention

However, in the force S, server-client type distribution form, the content distribution apparatus is The content data must be transmitted in response to the download request from the terminal device while streaming the content data to the terminal device, which increases the load on the content distribution device and the network.

[0006] As described above, when the load on the content distribution device or the network becomes heavy, the streaming distribution of the content data takes time s, and the streaming reproduction cannot be normally performed.

There may be a problem that downloading takes time.

[0007] For this reason, it is necessary to improve the performance of the content distribution apparatus or widen the network bandwidth, resulting in a great cost.

[0008] The present invention has been made in view of the above inconveniences, and in a content distribution system in which a user purchases content while viewing the content, content that can reduce the load on the content distribution device and the network. It is an object to provide a distribution system and method.

Means for solving the problem

[0009] In order to solve the above-described problem, according to one aspect of the present invention, a first distribution form in which content data is stream-distributed in a broadcast form from a content distribution apparatus to a terminal apparatus, and the plurality of terminal apparatuses A content distribution system having a second distribution form in which another terminal device that holds the content data distributes the content data based on a download request for content data of one terminal device An apparatus includes: a content receiving apparatus, a streaming receiving means for streaming receiving the content data to be streamed; a ring buffer area for temporarily storing content data received by the streaming receiving means; and the ring buffer Content data stored in the area When there is a download request operation regarding the streaming playback means for performing the streaming playback and the content data played back by the streaming playback means, in order to obtain the content data requested for download in the second distribution form, Identification information acquisition means for acquiring identification information of the content data, and the content data requested to be downloaded based on the identification information of the content data acquired by the identification information acquisition means. Device power download processing means for downloading and the down mouth Content data storage means for storing the content data downloaded by the code processing means.

[0010] With this configuration, the terminal device user is in the P2P (peer-to-peer) distribution mode, which is the second distribution mode, while the user of the terminal device is viewing the content that is stream-distributed in the broadcast mode from the content distribution device. Since the content can be downloaded, it is possible to reduce the load on the first distribution form that is a broadcast form, that is, the load on the content distribution apparatus and the network. Therefore, it is possible to provide a content distribution system that purchases content while viewing the content without increasing the performance of the content distribution device or the network at a great expense. In addition, since the distribution form for viewing and the distribution form for download are different, the influence of the download purchase processing on the distribution form for viewing can be suppressed, and the download time of content can be shortened. It becomes.

[0011] Further, in the content distribution system, the first distribution form is managed by a connection management device so that a plurality of terminal devices are logically connected in a hierarchical structure on a network with the content distribution device at the top. And the content data transmitted from the content distribution device is streamed and distributed by the relay function of the terminal device sequentially from the upstream terminal device to the downstream terminal device of the hierarchical structure. Content data distribution means for streaming distribution of the content data via the network, wherein the connection management device stores connection state information for storing connection state information of the terminal devices constituting the hierarchical structure; and The connection destination is introduced from the terminal device via the network. When a request is received, a connection destination candidate selection unit that selects a connection destination candidate from the connection state information stored in the connection state information storage unit, and the connection destination candidate selected by the connection destination candidate selection unit, Notification means for notifying the terminal device that has transmitted the connection destination introduction request via the network, and the terminal device transmits the connection destination introduction request to the connection management device via the network. Thereafter, when receiving a connection request to connect to the connection destination candidate notified from the connection management device and participate in the first distribution form, and a relay request for the content data from another terminal device, Streaming relay means for streaming-transferring the content data received to the terminal device that has made the connection request, wherein the streaming reception means connects the content data from the content distribution device via the network. It can be configured to receive via the connection destination candidate.

[0012] In this way, the first distribution form is a broadcast form having a hierarchical structure such as a tree shape or a chain shape, so that the content distribution device directly applies to all terminal devices participating in the content distribution system. It is possible to further reduce the load on the content distribution apparatus and network that do not require distribution of content data.

[0013] In addition, in the terminal device, a determination unit that determines whether or not the entire content data requested to be downloaded is stored in the ring buffer area, and the content data requested to be downloaded by the determination unit If it is determined that the entire content is stored in the ring buffer area, the content data stored in the ring buffer area is not stored in the content data storage without downloading the content data according to the second distribution form. The content data storage control means may be configured to be stored in the means.

With this configuration, the terminal device temporarily caches content data distributed in broadcast form in the ring buffer area, and the content data to be purchased is stored in the ring buffer area. Content data stored in the ring buffer area can be purchased. Therefore, the content data purchase process can be shortened compared to newly acquiring content data in the second distribution form. By increasing the capacity of the ring buffer area, it is possible to cache a large amount of content data distributed in broadcast form, so download time is reduced for users who often download content data after viewing it. Great shortening effect.

[0015] Further, in the content distribution system, the content distribution means for transmitting the content data distributed in the second distribution form to some terminal devices among the plurality of terminal devices, and the content distribution device. An identification information list storage unit that stores an identification information list including a plurality of identification information of content data to be distributed by streaming, and the identification information list stored in the identification information list storage unit is transmitted to the plurality of terminal devices. An identification information list transmitting means, and the terminal device has an identification information list receiving means for receiving an identification information list transmitted from the content input apparatus, and the identification information acquiring means The identification information of the content data requested to be downloaded may be acquired from the identification information list received by the identification information list receiving means.

With this configuration, a list of identification information of content data necessary for downloading content data in the second distribution form can be acquired from the content input device, and as a result, content download It is not necessary to acquire the identification information of the content data to be downloaded to the content input device every time processing is performed, and the load on the network and content input device can be reduced, and the download processing time can be shortened. Can do.

[0017] Further, the identification information list storage means of the terminal device may store an identification information list including identification information of content data other than content data that is stream-distributed by the content distribution device.

With this configuration, the content input device can store an identification information list including identification information of content data other than the content data that is streamed and distributed by the content distribution device, and is directly distributed in broadcast form. Content data other than content data can be acquired in the second distribution form.

[0019] Further, in the content distribution system, the content distribution device includes identification information transmission means for transmitting identification information of content data to be streamed by the streaming distribution means, and the terminal device includes the content distribution system. Identification information receiving means for receiving identification information of the content data transmitted from the distribution device, wherein the identification information acquisition means is configured to download the download request from the identification information of the content data received by the identification information receiving means. The identification information of the obtained content data may be acquired.

With this configuration, content data identification information necessary for downloading content data in the second distribution form is transmitted from the content distribution device to the terminal device. As a result, in the terminal device, Identify content data to download Since it is not necessary to request and acquire information from the content input device, the processing in the content input device can be reduced. Further, the content data identification information can be included in the header of the content packet used for streaming delivery and transmitted from the content delivery apparatus.

[0021] Further, a recording medium in which a program for causing a computer to function as each unit in the above-described terminal device is recorded in a computer-readable manner may be provided.

[0022] In order to solve the above-described problem, according to still another aspect of the present invention, a first distribution form for streaming distribution of content data from a content distribution apparatus to a terminal apparatus in a broadcast form, and the plurality of terminals Content in a content distribution system having a second distribution form in which another terminal device holding the content data distributes the content data based on a request to download content data of one terminal device between devices In the distribution method, the distribution device performs streaming distribution of the content data, and the terminal device performs streaming reception of the content data streamed from the distribution device via the network. And the terminal device received the streaming Temporarily storing content data in a ring buffer area, streaming the content data stored in the ring buffer area by the terminal device, and content data to be streamed by the terminal device When a download request operation is performed with respect to, in order to acquire the content data requested for download in the second distribution form, the step of acquiring identification information of the content data, and the terminal device Based on the data identification information, the step of downloading the content data requested for download from the terminal device of the second distribution form, and the terminal device stores the downloaded content data in content data storage means. Step to remember and Characterized in that it has.

The invention's effect

[0023] According to the present invention, content in a P2P (peer-to-peer) distribution form between terminal devices, which is the second distribution form, while a user of the terminal apparatus is viewing content that is stream-distributed in a broadcast form from the content distribution apparatus. Can be downloaded, so The load on the first distribution form, that is, the load on the content distribution device and the network can be reduced. Therefore, it is possible to provide a content distribution system that purchases content while viewing the content without increasing the performance of the network by using a large amount of cost. In addition, since the distribution form for viewing and the distribution form for download are different, the influence of the download purchase process on the viewing distribution form can be suppressed, and the download time of content can be shortened. It becomes possible.

Brief Description of Drawings

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

FIG. 2 is an explanatory diagram of a distribution operation of the first distribution form of the content distribution system according to the present embodiment.

FIG. 3 is a diagram conceptually showing functions of a ring buffer area in the terminal device of FIG. 1.

FIG. 4 is an explanatory diagram of a distribution operation of the second distribution form of the content distribution system according to the present embodiment.

FIG. 5 is a diagram showing an example of how a routing table is created by the DHT.

6 is a diagram showing an example of a routing table in the terminal device of FIG. 1.

FIG. 7 is a diagram illustrating an example of a state in which a terminal device participates in a second distribution form.

FIG. 8 is a diagram showing an example of a state in which a terminal device holding content data is searched by DHT routing.

FIG. 9 is a diagram showing an example of how content data is held in a terminal device by DHT routing.

FIG. 10 is a diagram showing an example in which a registration message is transmitted to a root terminal device by DHT routing.

FIG. 11 is a diagram showing an example of an index table in the terminal device of FIG. 1.

12 is a diagram showing an example of a display screen in the terminal device of FIG. 1.

FIG. 13 is a diagram showing another example of the display screen in the terminal device of FIG. 1.

FIG. 14 is a diagram showing a schematic configuration example of the content distribution apparatus in FIG. 1.

FIG. 15 is a diagram illustrating a schematic configuration example of the terminal device of FIG. 1. 16] A diagram showing a schematic configuration example of the connection destination management apparatus of FIG.

FIG. 17 is a diagram showing a schematic configuration example of the content input device in FIG. 1.

18] FIG. 18 is a diagram showing a schematic configuration example of the contact introduction device of FIG.

FIG. 19 is a flowchart showing overall processing in the content distribution apparatus of FIG. 1. FIG. 20] is a flowchart showing the entire processing in the terminal device of FIG.

Sono 21] is a flowchart showing the entire processing in the terminal device of FIG.

22] A flowchart showing the overall processing in the terminal device of FIG.

FIG. 23] is a flowchart showing the participation process in the second distribution form in the terminal device of FIG.

Sono 24] is a flowchart showing the input content receiving process in the terminal device of FIG. 1. Sono 25] is a flowchart showing the content purchasing process in the terminal device of FIG.

FIG. 26 is a flowchart showing content search processing in the terminal device of FIG. 1.

FIG. 27 is a flowchart showing an entire process in the connection management device of FIG. 1.

FIG. 28 is a flowchart showing overall processing in the content input device of FIG. 1.

FIG. 29 is a flowchart showing an entire process in the contact introduction device of FIG. 1. [30] FIG. 30 is a diagram showing an outline operation example of the content distribution system in Modification 2. Explanation of symbols

S content 信 3 communication system

1 Content distribution device

2 Terminal equipment

3 Connection management device

4 Content input device

5 Contact introduction device

6 network

130 Content Distribution Device Control Unit

230 Control unit of terminal equipment

330 Control part of connection management device 430 Content input device controller

530 Contact introduction device control unit

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. The embodiment described below is an embodiment when the present invention is applied to a content distribution system in which information to be distributed is content data such as music data and video data.

[0027] [1. Content distribution system configuration]

The content distribution system according to the present embodiment includes a first distribution form in which content data is stream-distributed in broadcast form from a content distribution apparatus to a terminal apparatus, and download of content data from one terminal apparatus between a plurality of terminal apparatuses. Another terminal device that holds the content data based on the request has a second distribution form in which the content data is distributed. Then, the user of the terminal device downloads the content data transmitted from the content distribution device from another terminal device according to the second distribution form while viewing the content data from the content distribution apparatus according to the first distribution form. It is configured so that it can be a force S.

[0028] As the first distribution form, there are a server client type broadcast form, a broadcast form with a tree-like hierarchical structure, and the like, but in this embodiment, the content data streamed from the content delivery apparatus is represented in a tree form. A description will be given by taking as an example a broadcast form in which a terminal device constituting a hierarchical structure receives and relays by P2P.

[0029] As the second distribution form, there are various distribution forms in which content data is transmitted and received between a plurality of terminal devices. In the present embodiment, a distributed hash table (DHT) (DHT) is particularly used for the P2P grid type distribution form. (Distributed Hash Table)) will be described as an example of a distribution form in which content data is transmitted and received between terminal devices, which is called a Pastry type.

FIG. 1 is a diagram showing a schematic configuration example of the content distribution system S according to the present embodiment. As shown in Fig. 1, the content distribution device 1, the terminal devices 2al, 2a2, 2bl to 2b4, 2cl to 2c8, the connection management device 3, the content input device 4, and the contact destinations that make up the content distribution system S The referral device 5 is a network 6 represented by the Internet. Distributed on top.

[0031] The content distribution device 1, the terminal devices 2al, 2a2, 2bl to 2b4, 2cl to 2c8, the connection management device 3, the content input device 4, and the contact introduction device 5 are used as information for identifying each device. A unique serial number (for example, MAC address) and IP (Internet Protocol) address (location information) are assigned, and these devices are connected to a network 6 as an example of a network via a router 10 or the like. Yes. Communication can be established by sending a packet containing a header with the destination IP address as the destination IP address and the source IP address as the source IP address.

[0032] Note that a device not directly related to the content distribution system S is also connected to the network 6, but is omitted here. In addition, when the terminal device 2al, 2a2, 2bl to 2b4, 2cl to 2c8, or any terminal device is shown, it may be referred to as the terminal device 2 for convenience.

In the example shown in FIG. 1, the content distribution device 1, the connection management device 3, the content input device 4, and the contact destination introduction device 5 have the functions of these devices in a single device that is an independent device. If you want to make it happen, ... In this case, the IP addresses of these devices are the same, and are distinguished by port numbers. Further, although the content distribution device 1 may be arranged for each broadcast channel, in the present embodiment, description will be made assuming that content data of a plurality of broadcast channels is distributed by one content distribution device 1.

[0034] [1. 1. About the first distribution form]

As shown in FIG. 1, the first distribution form of the content distribution system S is that a plurality of terminal devices 2al, 2a2, 2bl to 2b4, and 2cl to 2c8 are logically arranged in a tree-like hierarchical structure with the content distribution device 1 as a vertex. Connected and configured so that content data from the content distribution device 1 is streamed and distributed by the relay function of the terminal device 2 sequentially from the upstream terminal device 2 to the downstream terminal device 2 of the tree-like hierarchical structure. The This tree-like hierarchical structure is configured for each broadcast channel distributed by the content distribution apparatus 1.

[0035] In the first distribution form of this content distribution system S, a plurality of terminal apparatuses 2 are set with the content distribution apparatus 1 as the apex (here, the 0th layer for convenience) for each broadcast channel. Force It is managed by the connection management device 3 so as to be logically connected in multiple layers in an S-tree hierarchical structure. 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. Further, the terminal devices 2al and 2a2 may be referred to as a terminal device 2a for convenience, the terminal devices 2bl to 2b4 may be referred to as a terminal device 2b for convenience, and the terminal devices 2cl to 2c8 may be referred to as a terminal device 2c for convenience.

Here, content data distribution operation in the first distribution mode will be briefly described with reference to FIG. FIG. 2 is an explanatory diagram of the distribution operation of the first distribution form in the content distribution system S.

As shown in FIG. 2, the content data that is stream-distributed in the first distribution form by the content distribution device 1 is input to the content distribution device 1 by the content input device 4. That is, the content data is transmitted from the content input device 4 to the content distribution device 1, received by the content distribution device 1, and stored in the hard disk device.

[0038] As shown in FIG. 2, the connection management device 3 does not constitute a terminal device 2 that does not participate in the first distribution form in the content distribution system S, in other words, does not constitute any tree-like hierarchical structure of the broadcast channel. When the connection destination introduction request is received from the terminal device 2, the connection destination candidate to which the terminal device 2 is connected as an upstream device for receiving the streaming distribution based on the state of the tree-like hierarchical structure of the first distribution form, etc. (Content distribution device 1 or terminal device 2) is selected. Then, the connection management device 3 notifies the terminal device 2 of the location information (such as the IP address and port number of the connection destination candidate) and the communication protocol of the connection destination candidate thus selected. The connection destination introduction request is transmitted from the terminal device 2 when switching to another channel or when the connection with the upstream terminal is disconnected.

[0039] In the content distribution system S, when the communication protocol and port number are already fixed, the terminal device 2 does not need to be notified of the port number and communication protocol. Here, as a communication protocol, a dedicated communication protocol such as \ MMS (Microsoft Media Server) protocol, RTSP (Real Time Streaming Protocol), or the like may be used. Also, a dedicated data format is used as the content data format. ASF (Advanced Streaming Format), WMA (Windows (registered trademark) Media Audio), WMV (Windows (registered trademark) Media Video), etc. may be used.

[0040] Upon receiving the location information of the connection destination candidate from the connection management device 3, the terminal device 2 requests the connection destination candidate to participate (connect) to the content distribution system S with the location information as a destination, As a result, the terminal device 2 is incorporated into the hierarchical structure in the first distribution form of the content distribution system S. That is, the terminal device 2 can receive the content data distributed from the content distribution device 1.

[0041] In the first distribution form in the content distribution system S, the terminal device 2 participates in each channel one after another in this way, so that the plurality of terminal devices 2 have a tree-like hierarchical structure with the content distribution device 1 as a vertex. Logically connected to Then, the content data distributed by the content distribution device 1 is sequentially relayed to the downstream 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. 2, when content data is transmitted from the content distribution device 1 to the terminal devices 2al and 2a2 (first-layer terminal devices) and the terminal devices 2al and 2a2 receive the content data, The received content data is relayed sequentially to the downstream terminal devices 2bl to 2b4 (second-layer terminal devices). Upon receiving the content data, the terminal devices 2bl to 2b4 sequentially relay the received content data to the downstream terminal devices 2cl to 2c8 (third layer terminal devices). In FIG. 2, for the sake of easy understanding, only the hierarchical structure of one broadcast channel among a plurality of broadcast channels is shown.

[0043] Note that the terminal device 2 includes the location information of the terminal device 2 or the content distribution device 1 upstream of the position of the incorporated hierarchical structure and the location information of the terminal device 2 downstream of the position of the incorporated hierarchical structure. Are stored in a hard disk device 203 to be described later, and content data is relayed based on the stored location information. Further, the content data to be distributed is divided into a plurality of packets and sequentially distributed, and the data divided and distributed in this way is called a content packet.

[0044] The content data distributed to the terminal device 2 in this way is distributed to the terminal device 2 constituting the hierarchical structure for each broadcast channel. The distributed content data includes the power of content data such as music and movies, and playback time information. And The plurality of terminal devices 2 that have received the ten data perform reproduction of the content data that is sequentially transmitted based on the reproduction time information.

Here, the ring buffer area in the terminal device 2 will be described. FIG. 3 is a diagram conceptually illustrating a configuration in which content data is received using the ring buffer area in the terminal device 2 and is played back or relayed to the downstream terminal device 2.

[0046] When the terminal device 2 participates in the first distribution mode, the content packet streamed from the upstream device of the hierarchical structure in the participating broadcast channel is sequentially received by the stream receiver, and the received content packet The content data contained in is temporarily stored in the ring buffer area. The content data temporarily stored in the ring buffer area is taken out of the ring buffer area and played by the player as the playback means of the terminal device 2 at the playback time.

Here, as shown in FIG. 3, new content data is sequentially stored in the ring buffer area in the clockwise direction, and the oldest content data is rewritten to new content data. In other words, if A is the point written to the ring buffer area by the stream receiver, this point A moves clockwise.

Note that the ring buffer area in FIG. 3 is conceptually shown, and the control means of the terminal device 2 that has not actually formed a ring shape has accumulated in a predetermined address area in the storage area. This is achieved by sequentially rewriting the oldest content data with new content data.

[0049] In addition, the playback time information is stored in the content data as described above, and the content data (here, the playback time information that matches the current time among the content data stored in the ring buffer area). The content data at point B in Fig. 3) is taken out of the ring buffer area and played sequentially.

[0050] With such a ring buffer area, content data loss that occurs intermittently depending on the state of the network 6 by the playback time is handled while storing the content data before the playback time. In other words, the content distribution device 1 distributes content data while ensuring a margin sufficient to perform packet loss compensation processing. Note that the packet loss compensation process is a process for requesting retransmission of a packet to a higher-level device and transmitting the packet again from the higher-level device when a packet from the higher-level device does not arrive after waiting for a certain period of time. . In the loss compensation process, a series of processes must be performed in this way, and it takes a certain amount of time, so it is necessary to secure a margin as described above.

Here, when two other terminal apparatuses 2 are connected downstream of the hierarchical structure, as shown in FIG. 3, the terminal apparatus 2 is provided with two stream transmitters. This stream transmitter stores the content data stored in the ring buffer area in the data area of the content packet for each predetermined amount, generates a content packet, and sends the content packet to another terminal device 2 connected downstream. Send content packets sequentially.

[0052] In the terminal device 2 in the first embodiment, the content data included in the content packet transmitted from the upstream device is extracted and stored in the ring buffer area. You may make it accumulate | store in. In any case, the stream transmitter transmits the content packet in which the information of the transmission destination and the transmission source of the content packet received by the stream receiver is replaced to the downstream terminal device 2. The stream receiver corresponds to a stream receiving means described later, the player corresponds to a stream reproducing means described later, and the stream transmitter corresponds to a stream relay means described later.

[0053] In this way, the terminal device 2 provides a ring buffer area for temporarily storing content data, thereby compensating for packet loss while prebuffering the content packet, and is generated on the network 6 path. The effect of packet loss is avoided.

As described above, in the first distribution form of the content distribution system S, the content data transmitted from the content distribution device 1 is stream-distributed to the plurality of terminal devices 2 and the plurality of terminal devices 2 at the same time. Content can be played back. That is, the content distribution system S uses P2P to realize broadcast distribution in a plurality of terminal devices 2.

[0055] [1. 2. Second delivery mode]

Next, referring to FIG. 4, the schematic configuration of the second distribution form in the content distribution system S Etc. will be described. FIG. 4 is a diagram showing a second distribution form in the content distribution system S according to the present embodiment. This second distribution form is a P2P grid type distribution system. In this embodiment, a distributed hash table (hereinafter referred to as “DHT” (Distributed Has h Table)) is used to distribute on the network. A distribution form in which content data is transmitted and received between a plurality of arranged terminal devices 2 will be described as an example.

[0056] [1.2.1 Overview of DHT]

First, the algorithm using the DHT according to this embodiment will be described.

[0057] In the second distribution mode of the content distribution system S, when the terminal devices 2 exchange information with each other, they must know the IP addresses as the location information of each other.

[0058] For example, in a system in which content is shared among a plurality of terminal devices, all the terminal devices 2 that participate in the network 6 and each of the terminal devices 2 that participate in the network 6 are registered. Knowing the IP addresses of terminal devices 2 is a simple technique. When the number of terminals becomes tens of thousands and hundreds of thousands, it is not realistic to remember the IP addresses of all the terminal devices 2. Absent. Also, if the power of any terminal device is frequently turned ON or OFF, the IP address of the arbitrary terminal device stored in each terminal device 2 is frequently updated, which makes operation difficult.

[0059] Therefore, in one terminal device 2, only the minimum necessary IP addresses of some of the terminal devices 2 participating in the network 6 are stored, and the IP For the terminal device 2 that does not store an address, a system has been devised that delivers content by transferring information between the terminal devices 2.

[0060] As an example of such a system, an overlay network is constructed by an algorithm using DHT. That is, this overlay network means a network constituting a virtual link (logical connection) formed using the existing network 6.

[0061] In the present embodiment, it is assumed that an overlay network constructed by an algorithm using DHT is used, and the terminal device 2 arranged on the overlay network is connected to the second distribution form of the content distribution system S. Terminal device 2 participating in Yeah. Of the terminal devices 2 that are physically connected to the network 6, the terminals that participate in the first distribution mode of the content distribution system S (in other words, the hierarchical structure having the content distribution device 1 as the apex). Device 2 also participates in the second distribution form of content distribution system S at the same time. Participation in the second distribution form of the content distribution system S is performed by the terminal device 2 not yet participating sending a participation request to the terminal device 2 already participating.

[0062] A unique number (unique number) is assigned to each terminal device 2 as a terminal ID that is an identification number of each terminal device 2 participating in the second distribution form of the content distribution system S. This number must have enough bits to accommodate the maximum number of terminal devices. For example, if a 128-bit number is used, 2 ¹²⁸ 340 X 10 ³⁶ terminal devices can be operated.

[0063] More specifically, the terminal ID of each terminal device 2 is a unique hash function (hash algorithm) that is unique to each terminal device 2, such as the IP address or serial number of each terminal device 2. ) Is a hash value obtained by hashing, and is distributed evenly in one ID space. The terminal ID obtained by hashing with a common hash function in this way has a very low probability of having the same value if the IP address or serial number is different. Since the hash function is publicly known, detailed explanation is omitted. In this embodiment, a value obtained by hashing an IP address (global IP address) with a common hash function is used as a terminal ID.

[0064] Further, as shown in FIG. 4, content distributed from one terminal device 2 to another terminal device 2 is provided to a plurality of terminal devices 2 participating in the second distribution form of the content distribution system S. Data is distributed by the content input device 4 and input to the terminal device 2, and unique identification information (hereinafter referred to as “content ID”) for each content data is also given to the content data. .

[0065] Then, the content ID has the same length as the terminal ID (for example, 128 bits). For example, a keyword such as a content name (content title) or outline information (summary) of the content is stored in the terminal. It is hashed by the same hash function as when ID is obtained (that is, placed in the same ID space as the hash value of the IP address of terminal device 2). The terminal device 2 having a terminal ID that is closer (for example, the higher-order digits match more), the link information to the terminal device 2 that holds content data (hereinafter referred to as “content holding terminal device”), that is, content holding Holds the IP address that is the location information of the terminal device.

[0066] The content holding terminal device is randomly determined by the content input device 4.

That is, the content input device 4 randomly determines one or more terminal devices 2 that should hold the content data, and transmits the content data to the terminal device determined in this way. The terminal device that has received the content data from the content input device 4 functions as a content holding terminal device by holding the content data in the storage unit. As a result, the content data is distributed and arranged on the content distribution system S without any bias.

[0067] It should be noted that even if the content data is different, the same keyword (for example, the name of the content) is assumed. In this case, since the same hash value is obtained, in order to avoid this, The keyword to be hashed may be, for example, a combination of content name and copyright information (for example, performer name, director name, original author name, singer name, composer name, or songwriter name). In the present embodiment, content names are not duplicated, and the content name is a keyword.

[0068] In this way, since the terminal ID and content ID assigned to each terminal device 2 and each content data are generated by a common hash function, they are stored on the same ring-shaped ID space as shown in FIG. It can be thought of as scattered and existing without much bias. This figure shows a terminal ID and content ID assigned in 32 bits. In the figure, the dot indicates the terminal ID, the square indicates the content ID, and the ID increases counterclockwise.

Next, which content data is held in which terminal device 2 is determined under a certain rule. In the present embodiment, the rule is that “the terminal device 2 that manages content data having a certain content ID is the terminal device 2 having a terminal ID close to that content ID”. Here, the definition of “close” does not exceed the content ID, and is the power to minimize the difference between the content ID and the terminal ID. When assigning to, it should be consistent. In the example shown in FIG. 4, based on this definition, the content IDa is a terminal ID close to the content IDa (hereinafter “ Called “Terminal &”. The content IDb is managed by the terminal device 2 having a terminal ID (hereinafter referred to as “terminal”) close to the content IDb, and the content IDc is close to the content IDc. It is managed by a terminal device 2 having a terminal ID (hereinafter referred to as “terminal”).

[0070] Here, "management" does not mean that content data is retained, but "knows the power with which content data is retained in any terminal device 2". Means. That is, in FIG. 4, the terminal device 2 having the terminal IDa knows which terminal device 2 holds the content data having the content IDa, and has the terminal device 2 having the terminal IDb and the terminal IDc. Similarly, the terminal device 2 also knows whether the content data having the content IDb and the content data having the content IDc are held in the terminal device 2 that is out of position. It will be.

In this way, the terminal device 2 that knows which terminal device 2 holds certain content data is called a root terminal device of the content data. That is, the terminal device 2 having the terminal ID a is a root terminal device for content data having the content IDa, and the terminal device 2 having the terminal IDb is a root terminal device for content data having the content IDb, The terminal device 2 having IDc is a root terminal device for content data having content IDc.

Here, the content input device 4 distributes to the terminal device 2 in addition to the function of distributing the content data to the terminal device 2 so that the terminal device 2 in the content distribution system S becomes the content holding terminal device. A plurality of pieces of content data (in other words, content data held by the content holding terminal device) are generated and provided to the terminal device 2 by generating an identification information list that is an identification information list in which the content name and content ID are associated with each other. It has a function to do.

[0073] Further, in the second distribution form of the content distribution system S, the contact introduction device 5 is arranged. The contact introduction device 5 is configured such that when a terminal device 2 that has not participated in the second distribution form of the content distribution system S receives a request to participate in the second distribution form, It has a function of notifying the location information of the terminal device 2 that has already participated in transmitting the message (hereinafter referred to as “contour outside terminal device”). [0074] [1.2.2 Create routing table]

Here, an example of a method for creating a routing table used in DHT will be described with reference to FIG. Figure 5 shows an example of how the routing table is created by the DHT.

First, the ID space as shown in FIG. 5 (a) is divided into several areas. Actually, about 16 divisions are often used, but in order to simplify the explanation, here, 4 divisions are used, and the ID is represented by a quaternary number having a bit length of 8 bits. An example in which the terminal ID of the terminal device 2N is “1133” and the routing table of the terminal device 2N is created will be described.

[0076] (Level 1 routing)

First, if the ID space is divided into four parts, each area is represented by a quaternary number with different maximum digits. Four areas “0XXX”, “1XXX”, “2XXX”, “3XXX” (where X is a natural number from 0 to 3) The same shall apply hereinafter). Since the terminal ID of the terminal device 2N itself is “1133”, the terminal device 2N exists in the area “1XXX” in the lower left in FIG. 5 (a). The terminal device 2N is a terminal existing in an area (that is, an area of “0 XXX”, an area of “2XXX”, an area of “3XXX”) other than its own area (that is, an area of “1XXX”). Select device 2 appropriately, and store the location information of the terminal ID, that is, the IP address of the terminal ID in the level 1 table. Figure 6 is an example of a level 1 table. In this table, “0100” is selected as the terminal ID of the area “0XXX”, “2133” is selected as the terminal ID of the area “2XXX”, and “3213” is selected as the terminal ID of the area “3 XXX”. It shows the state to be. Note that the second column of level 1 indicates the terminal device 2N itself, so there is no need to store the IP address.

[0077] (Level 2 routing)

Next, among the areas divided into four by the above routing as shown in Fig. 5 (b), the area "1XXX" where the user exists is further divided into four, and further four areas "10XX", "11XX", and "12XX" , “13XX”. Then, similarly to the above, the terminal device 2 existing in the area other than the area “l lxx” where the user exists is appropriately selected, and the IP address which is the location information of the terminal ID is stored in the level 2 table. Figure 6 shows an example of a level 2 table. In this table, the terminal ID of the area “10XX” is the terminal ID of the area “1003” and the area “12XX”. In this case, “1313” is selected as the terminal ID of the areas “1221” and “13XX”. Note that the second column of level 2 is the area “11XX” where the terminal device 2N exists, and since it is tabulated at level 3 described later, it does not store the IP address. If the terminal device 2 does not exist in the above area, the terminal ID and IP address fields are blank.

[0078] (Level 3 routing)

Furthermore, among the areas divided into four by the above routing, the area “11 XX” where the user exists is further divided into four, and further divided into four areas “110 乂” “111 乂”, “112X”, “113X”. . Then, similarly to the above, the terminal device 2 existing in an area other than the area “113X” in which it exists is appropriately selected, and the IP address as the location information of the terminal ID is stored in the level 3 table. Figure 6 is an example of a level 3 table. The 4th IJ of Revenor 3 is the area where the terminal device 2N is present, and since it is tabulated at level 4 (to be described later), the IP address is not stored. If there is no terminal device in the area, the terminal ID and IP address fields are blank.

[0079] By creating a routing table in the same way up to level 4 as shown in FIG. 6, all 8-bit IDs can be covered. As the level goes up, white space becomes more noticeable in the table.

[0080] All the terminal devices 2 each create and own the routing table created according to the method described above. In this way, each terminal device 2 has a routing table that associates terminal IDs (identification information) and IP addresses (location information) of some of the terminal devices 2 among the plurality of terminal devices 2 in the content distribution system S. The routing table is stored in a routing table storage means described later.

By the way, when the terminal apparatus 2 has not participated in the second distribution form, the terminal apparatus 2 does not know the location information of the terminal apparatus 2 participating in the second distribution form. Therefore, when the terminal device 2 participates in the second distribution mode, it generates a routing table as described in the next section.

[0082] [1. 2. 3. Participation in the second distribution form]

Next, an example of a method in which the terminal device 2 that has not participated in the second distribution form in the content distribution system S participates in the second distribution form will be described with reference to FIG. Figure 7 FIG. 10 is a diagram illustrating an example of a state in which a terminal device 2 that has not participated in the second distribution form (hereinafter referred to as “new participation terminal apparatus”) participates in the second distribution form. A procedure for the newly participating terminal apparatus 2M to participate in the second distribution form in the content distribution system S will be described.

[0083] First, a new participation terminal apparatus 2M that has not participated in the second distribution form sends a participation message to the contact introduction apparatus 5 in order to participate in the second distribution form of the content distribution system S. Request location information of terminal device 2 (hereinafter referred to as “contact destination terminal device”) to be transmitted (hereinafter referred to as “inquiry of external terminal device outside contour”).

[0084] The new participation terminal device 2M transmits a participation message to the contact destination terminal device when the location information of the contact destination terminal device to which the contact destination introduction device 5 should transmit the participation message is sent. . Here, the destination identification information of the participation message is the terminal ID of the new participation terminal device 2M. That is, when newly participating terminal apparatus 2M participates in the second distribution mode, it generates a participation message using the hash value “2133” of the IP address of its own apparatus 2 as destination identification information.

[0085] When the contact destination terminal device receives the participation message transmitted from the new participation terminal device 2M, the contact destination terminal device determines whether or not this participation 0 message is a message addressed to the contact destination terminal device. To do. Whether the message is addressed to the contact destination terminal device is determined based on the destination identification information and the routing table. Specifically, it is determined whether or not the destination identification information is close to the identification information addressed to the contact destination terminal device. That is, for the destination identification information, whether the identification information of the nearest terminal device is itself from the identification information of the terminal device stored in the routing table held by the contour destination terminal device itself. It is determined whether it is another terminal device. When the identification information of the other terminal device is closer to the destination identification information than the identification information of the contact destination terminal device, the contour destination terminal device that has received the participation message is held by the contour destination terminal device itself. Referring to the level 2 of the routing table that is being used, transfer the participation message to the terminal device 2B that knows the IP address among the terminal devices 2 belonging to the “2XXX” area. The information of the routing table level 1 table stored in the routing table storage means is transmitted to the newly participating terminal device 2M.

[0086] In this way, transfer of the participation message is performed in a manner that adapts the digits of the content ID in order from the top. The information of each level of the routing table is sequentially transmitted. The transfer of the participation message ends when the terminal device 2 that is closest to the destination identification information is finally reached. The mechanism that forwards messages such as the participation message to the target terminal device as described above is called DHT routing.

Thus, the newly participating terminal device 2M obtains information on each level of the routing table from the terminal device 2 that has received the participation caro message in order from the information on the higher level. In this way, the newly participating terminal 2 generates a routing table necessary for participating in the second distribution form.

[0088] [1. 2. 4. Content data search method]

Next, with reference to FIG. 8, an example of a search method for the terminal device 2 holding content data will be described. FIG. 8 is a diagram illustrating an example of a state in which the terminal device 2 that holds content data by DHT browsing is searched.

Here, the procedure when terminal device 2N with terminal ID “1133” searches for content data having content ID “3020” will be described. Hereinafter, a terminal device that searches for content data and requests reception of content data in this way is referred to as a “request terminal device”.

[0090] The requesting terminal device 2N refers to the level 1 table of the routing table held by itself, and uses the terminal ID of the terminal device having the terminal ID in the same area as the content ID "3020" as destination identification information. A transmission request (hereinafter referred to as “content search message”) of content holding terminal device information (information including location information of the content holding terminal device) is transmitted. That is, since the content ID “3020” is an area “3XXX”, the terminal device 2 belonging to the area “3X XX” knows the IP address (that is, the routing table held by itself). Content search message is transmitted to terminal device 2A (terminal ID “3213”). Thus, the content search message includes a content ID that is unique identification information corresponding to the content, and this content ID is used as destination identification information in the content search message.

According to the example shown in FIG. 8, the IP address of the terminal device 2A whose terminal ID is “3213” is stored in the routing table (see FIG. 6) of the request terminal device 2N. The list terminal device 2N transmits a content search message to the terminal device 2A whose terminal ID is “3213”.

Next, the terminal device 2A that has received the content search message determines whether or not the content search message is a message addressed to the terminal device 2A. Whether the message is addressed to the terminal device 2A is determined based on the destination identification information and the routing table. Specifically, it is determined whether or not the destination identification information is close to the identification information of its own terminal device 2A. That is, for the destination identification information, the terminal device 2A itself stores the identification information of the terminal device that is stored in the routing table held by the terminal device 2A itself. It is determined whether it is a terminal device or another terminal device. Here, since the identification information of the other terminal device is closer to the destination identification information than the identification information of its own terminal device 2A, the terminal device 2A has the routing table held by the terminal device 2A itself. Referring to the level 2 table, out of the terminal devices 2 belonging to the “30XX” area, the content search message is transferred to the terminal device 2B (terminal ID “3031”) that knows the IP address.

[0093] In this way, the content search message is transferred in accordance with the order of the content ID digits in the ascending order, and the content search message is transferred, and finally the terminal device 2C (terminal ID “3011”) manages the content data. ), That is, when the root terminal device arrives, the root terminal device searches the content ID “3020” included in the content search message from the below-described index information managed by itself, and The content holding terminal that owns the content data is returned to the requesting terminal device 2N with the IP address of the terminal device.

In this way, the request terminal device 2N receives from the root terminal device 2C the content data location information of the content ID “3020”, that is, the IP of the content holding terminal device that holds the content data of the content ID “3020”. You will receive and know the address, and you will download the content data from the content holding terminal device.

[0095] [1. 2. 5. How to register to index table]

In the second distribution form in the content distribution system S, a method for publishing new content data so that it can be seen by other terminal devices 2 on the content distribution system S. To say.

As shown in FIG. 9, the second distribution form of the content distribution system S in the present embodiment is that each content holding terminal device is different from the terminal device 2 in which the content input device 4 is each content holding terminal device. Content data to be managed content for each is transmitted. The content holding terminal device that has received the content data to be managed from the content input device 4 stores the received content data in the hard disk device 203 described later.

[0097] As shown in FIGS. 9 and 10, the content holding terminal device to which the content data has been distributed has a registration request message for content holding terminal device information including location information and identification information of the content holding terminal device (see FIG. 9 and FIG. 10). (Hereinafter referred to as “content registration message”) toward the terminal device having the same terminal ID as the content ID obtained from the content name or the like (whether or not this terminal device actually exists is unknown at this point). ,.)Send. Then, this content registration message is also successively transferred according to the routing table in the same manner as the content search message, and is transferred to the terminal device 2 having the terminal ID closest to the content ID included in the content registration message. Then, when the terminal device 2 determines that there is no other destination terminal device, it determines that the terminal device 2 itself should be the root terminal device of the content, as shown in FIG. The content ID that is the content holding terminal device information included in the content registration message, the IP address of the content holding terminal device, and auxiliary information (attribute information such as title, genre, extended information, (Right information, streaming time, etc.) 222 is stored in.

[0098] When the IP address, which is the location information of the content holding terminal device, is registered in the index table 222 of the root terminal device in this way, the content registered in the index table in response to the content search message from the requesting terminal device thereafter. The location information of the holding terminal device is returned to the requesting terminal device. In this way, in this embodiment, the content distributed from the content input device 4 is registered in the content holding terminal device and can be searched via the root terminal device, so that the content can be stored in other terminal devices. Publish.

[0099] As shown in FIG. 11, the index table 222 includes the location of the content holding terminal device. This is a table for storing content holding terminal device information including information (location information) such as an IP address. In this index table 222, in addition to the IP address of the content holding terminal device, the time when the content holding terminal device was introduced is stored for each row (predetermined storage area) as content holding terminal device information.

[0100] [1. 3. Relationship between first and second delivery modes]

Next, the outline of the relationship between the first distribution form and the second distribution form in the content distribution system S will be briefly described with reference to FIG.

[0101] When each terminal device 2 participates in the content distribution system S, it participates in the second distribution form at the same time as participating in the first distribution form. In other words, when it is incorporated in the tree-type distribution structure in the first distribution form, it is also incorporated in the overlay network constructed by the algorithm using the DHT in the second distribution form.

[0102] Each terminal device 2 receives the streaming content data streamed from the content distribution device 1 in the first distribution form in the content distribution system S, and stores it in the ring buffer area of its own terminal device. The content data stored in the ring buffer area is retrieved from the ring buffer area and streamed at the playback time. Streaming playback refers to a playback method in which content data is transmitted while being divided and received, and is played back. The entire content data is received all at once and then played back after downloading. Are different. Streaming delivery is a transmission method that delivers so that streaming playback is possible. Such streaming playback and streaming distribution can be achieved by adopting a streaming communication protocol and content data format.

In the present embodiment, the content data streamed from the content distribution device 1 is sequentially fetched one after another for each broadcast channel in the broadcast format, and sequentially streamed to each terminal device 2. be delivered.

[0104] In this way, the terminal device 2 performs streaming playback of the content data distributed from the content distribution device 1, so that the user of the terminal device 2 can view the content data.

[0105] The user of the terminal device 2 views the content data distributed from the content distribution device 1. If you have content data you like while listening, you can download the content data. That is, as shown in FIG. 12, in the internal display 210 (to be described later) in the terminal device 2, the content video being reproduced is displayed in the content display frame 21 (a predetermined video is displayed when the content is music). However, the content information (in this case, the name of the content) being played is displayed in the title name display frame 22. In addition, a download button 23 is displayed on a later-described built-in display 210 in the terminal device 2. The download button 23 is a GUI (Graphical User Interface) displayed on the built-in display 210 and can be operated by the remote control 208 of the terminal device 2. The content information is transmitted together with the content data from the content distribution device 1, and is information stored in the header portion of the content data.

[0106] If the user of the terminal device 2 likes the content data transmitted from the content distribution device 1, the user performs a download request operation. For example, the download request is operated by operating the remote control 208 and selecting the download button 23 on the built-in display 210. The terminal device 2 is configured to download content data in the second distribution form when the download button 23 is selected. That is, when the download button 23 is selected, the terminal device 2 acquires the content ID that is the identification information of the content data requested for download from the identification information list acquired when participating in the second distribution form. .

[0107] The terminal device 2 that has acquired the content ID refers to the routing table of its own terminal device as the requesting terminal device, and transmits a content search message using the content ID of the content data requested for download as destination identification information. . The content search message is transferred in a manner that adapts the content ID digits in order from the top, and finally the root terminal that manages the location information of the content holding terminal device that holds the content data requested to be downloaded. Get to the device. The root terminal device searches for the content ID included in the content search message from the index information that it manages and records the content ID corresponding to the content ID of the content holding terminal device. The location information is transmitted to the request terminal device.

[0108] The request terminal device has made a download request to the content holding terminal device. Requests transmission of content data via the network 6. The content data is received via the network 6 from the content holding terminal device that holds the content data requested to be downloaded, and stored in content data storage means to be described later.

[0109] In this way, if the user of terminal device 2 is watching content data that is streamed in the first distribution form, and if there is content content that she likes, the content data is transferred to the _second distribution form. Can be downloaded by.

[0110] By the way, the display on the built-in display 210 of the terminal device 2 may be as shown in FIG. 13 instead of as shown in FIG. That is, a plurality of pieces of content data streamed from the content distribution device 1 are displayed. The content name of the content data currently being streamed is emphasized by capitalizing it. In FIG. 13, the name of the content at the center (content 4) is the content data that is currently stream-played, and above it is the content data content content that has been stream-played in the past. Below, the names of the content data to be streamed and played in the future are displayed in sequence.

[0111] When selecting content data to be downloaded, the selection frame 24 displayed on the internal display 210 is moved up and down to the content name display position of the content data to be selected, and the download button 23 is pressed with the remote control 208. Line 5 by operating.

[0112] In this way, content data that has been played back in the past and content data that will be played back in the future in addition to the content data that is currently played back can be downloaded, so that the user of the terminal device 2 can be downloaded. This makes it possible to provide more convenient services and increase the amount of content data downloaded.

[2. Description of Configuration of Content Distribution Device 1]

Next, the configuration and operation of the content distribution apparatus 1 will be described in more detail with reference to FIG.

FIG. 14 is a diagram showing a schematic configuration example of the content distribution apparatus 1 in the present embodiment. The content distribution apparatus 1 is applicable to a general server computer, and stores (stores) a CPU (Central Processing Unit) 102 and various programs as shown in FIG. Between the terminal device 2, the connection management device 3, and the content input device 4 via the network 6 and the main storage device 105 as a rewritable main storage device, the hard disk device 103 that stores various data, etc. Network interface 104 that communicates with the device, peripheral device control chip 106 that controls input means such as a keyboard 107 and mouse 108 that can input predetermined information, and image data from the CPU 102, and an internal video memory (not shown) ) And the data written to this video memory on the internal display 110 (to be described later), the built-in display 110 that displays the data according to the signal transmitted from the video chip 109, and the FM sound source (Frequency Modulation) ) And Wave Table sound source, etc., and the audio output from the sound source chip 111 A built-in speaker 112 which converts the signals into sound waves, is configured to include the various components of these is Ru les, are connected to each other via a system bus 101.

Note that the network interface 104 is connected to the network 6 via the router 10a. This router 10a corresponds to the router 10 shown in FIG.

In the present embodiment, the control unit 130 is configured by the CPU 102 and the main storage device 105. In addition, the content distribution apparatus 1 includes the built-in display (liquid crystal display, etc.) 110 as described above. For example, a broadcast operator who operates the content distribution system S looks at the built-in display 110. The ability to input predetermined information from input means. In the present embodiment, the built-in display 110, the built-in speaker 112, and the like are not limited to the force S built in the content distribution apparatus 1, but may be connected separately, for example.

[0117] (About main memory 105)

In addition, the main storage device 105 includes a ○ S (operating system) program 117 for providing basic functions as a computer of the content distribution device 1 and content stored in the broadcast content storage area of the hard disk device 103. Stream control program 115 for retrieving data and streaming to terminal device 2 and location information (IP address, port number, etc.) of each terminal device 2 connected to each broadcast channel Topology management program 116, screen control program 118 for controlling built-in display 110, and decoding of encoded music content data A music decoder program 119, a ring buffer area 120 for temporarily storing the content data read from the broadcast content data 113 stored in the hard disk device 103 before being transmitted to the terminal device 2, and a downstream terminal device The content management program 121 received from the content input device 4 for each broadcast channel from the content input device 4 and stored in the hard disk device 103 is stored. These are read by the CPU 102 and are read by the CPU 102. The function according to the program is executed.

[0118] Here, the S program 117 is read and executed by the CPU 102, so that functions related to input / output of the keyboard 107 and mouse 108, memory management of the main storage device 105 and the hard disk device 103, etc. This makes it possible to execute the basic functions of the computer that is the content distribution apparatus 1 of the above.

Then, in a state where the S program 117 is executed by the CPU 102, the above-described stream control program 115, topology management program 116, screen control program 118, music decoder program 119, and content management program 121 are stored in the main storage device. It is read from 105 and executed.

[0120] The OS program 117, the stream control program 115, the topology management program 116, the screen control program 118, the music decoder program 119, the content management program 121, etc. are stored in the main memory from, for example, a server connected to the network 6. It may be downloaded to the device 105 or may be recorded on a recording medium (storage medium) such as a CD-ROM and then read into the main storage device 105 via the recording medium. Les.

[0121] (About control unit 130)

As described above, the control unit 130 includes the CPU 102 and the main storage device 105, and the CPU 102 reads and executes the various programs 115 to 119 and 121 stored in the main storage device 105, thereby distributing contents. The entire apparatus 1 is controlled in an integrated manner and functions as a content data distribution means described later. The CPU 102 executes the stream control program 115 as a content data distribution means, etc., and the CPU 102 executes the topology management program 116, so that the topology management The CPU 102 executes the screen control program 118, and as a display control means, the CPU 102 executes the music decoder program 119. As a playback means, the CPU 102 executes the content management program 121. Therefore, they function as distribution content receiving means and distribution content storage means, respectively. Further, the hard disk device 103 is used as content data storage means for storing content data.

[0122] (About distribution content receiving means and distribution content storage means)

The distribution content receiving means requests the content input device 4 to transmit content data, and receives the content data transmitted from the content input device 4 and the name of the content. Also, the distribution content storage means stores the received content data as the broadcast content data 113 in the hard disk device 103 when the content data is received from the content input device 4 by the distribution content reception means.

[0123] Also, the hard disk device 103 stores in advance broadcast program information for storing the order of the content data to be broadcast on each broadcast channel, and the distribution content receiving means uses the content information based on the program information. The content data requested to be transmitted to the input device 4 is determined, and a transmission request to the content input device 4 is made.

[0124] The distribution content receiving means transmits the broadcast program information to the hard disk device 403 of the content input device 4 based on the broadcast program information, instead of making a transmission request for content data to the content input device 4. The content input device 4 may store the content data sequentially based on the broadcast program information. In this case, the content distribution device 1 sequentially distributes the content data input by the content input device 4 to the downstream device for each broadcast channel.

[0125] (Content data distribution means)

The content data distribution means distributes the content data via the network 6. In other words, the broadcast content data stored in the hard disk device 103 is taken out and streamed to the terminal device 2 (for example, the top-level terminal device when connected in a tree type) or the like logically connected via the network 6. To deliver. Na The content data includes information such as the name of the content.

[0126] Streaming delivery to the terminal device 2 or the like by the content data delivery means is executed according to the following procedure.

[0127] The content data distribution means sequentially extracts the content data based on the broadcast program information from the broadcast content data 113 stored in advance in the hard disk device 103, and stores it in the ring buffer area 120.

[0128] Next, the content data distribution means encodes the content data extracted from the ring buffer area 120 into a data format for streaming distribution, for example, a data format such as ASF, WMA, or WMV.

[0129] After that, the content data distribution unit stores the corresponding content data in the content packet while dividing the content data for each predetermined capacity with respect to the connected terminal device 2 and the like. Send to content packet.

[0130] Note that the content data distribution means may flow the content selected by the input means such as the keyboard 107 by the DJ or the like. However, the selectable content is content data distributed from the content input device 4.

[0131] (About topology management means)

The content distribution device 1 is assigned with a plurality of broadcast channels, and the topology management means is the location information of the terminal devices 2 participating in the first layer of the tree-like hierarchical structure constituted by the assigned broadcast channels. (IP address, port number, etc.) are managed for each broadcast channel. The above distribution means uses the IP address of the terminal device 2 managed by the topology management means as the destination address, and uses the distribution IP address as the transmission source.

[0132] (Display control means)

The display control means has a function of controlling the video chip 109 and the built-in display 110 to display content data and various information. That is, the display control means can control how the content video and various information are displayed on the built-in display 110.

[0133] (Reproduction means) The reproduction means has a function of displaying content data from the broadcast content data 113 on the built-in display 110 and outputting it from the built-in speaker 112.

[3. Description of configuration of terminal device 2]

Next, the configuration and operation of the terminal device 2 will be described in more detail with reference to FIG. FIG. 15 is a diagram illustrating a schematic configuration example of the terminal device 2 in the present embodiment.

The terminal device 2 can be a general personal computer or a dedicated terminal. As shown in FIG. 15, a rewritable main memory that stores (stores) a CPU (Central Processing Unit) 202 and various programs and the like. Storage device 205, hard disk device 203 for storing various data and the like, content distribution device 1, connection management device 3, content input device 4, contact destination introduction device 5 and other terminals via network 6 A network interface 204 for performing wired communication with the device 2, a user input remote control 208 for transmitting and receiving a predetermined infrared signal that allows the user to remotely operate the terminal device 2, and the user input An infrared port 207 for performing infrared communication with the remote controller 208, a peripheral device control chip 206 for controlling the infrared port 207, A video chip 209 that receives image data from the CPU 202 and writes it to an internal video memory (not shown) and displays the data written to the video memory on a built-in display 210 described later, and a signal transmitted from the video chip 209 A built-in display 210 that performs display according to the sound source, a sound source chip 211 having a sound source such as an FM sound source (Frequency Modulation) or a Wave Table sound source, and a built-in speaker 212 that converts an audio signal output from the sound source chip 211 into sound These various components are connected to each other via a system bus 201.

In the present embodiment, the CPU 202 and the main storage device 205 constitute a control unit 230. The network interface 204 is connected to the network 6 via the norator 10b. This router 10b corresponds to the router 10 shown in FIG.

[0137] With the user input remote control 208 as described above, operations such as purchase of content in the content distribution system S are possible.

[About main memory 205]

The main storage device 205 provides basic functions of the terminal device 2 as a computer. OS program 217 to be provided and in the first distribution form, the content data to be streamed and distributed directly from the content distribution device 1 or to another terminal device 2 is stream-received and transmitted to the downstream terminal device 2 by streaming. For the stream control program 215 and the location information (IP address and port number) of the upstream terminal device 2 (or the content distribution device 1) connected in the tree in the first distribution form. Topology management program 216 for managing location information of device 2, screen control program 218 for controlling built-in display 210, and content data streamed from upstream devices in the first distribution mode It can be decoded and streamed or downloaded in the second distribution form. A music decoder program 219 for playing back the content data stored in the hard disk device 203, a ring buffer area 220 having a predetermined storage capacity and temporarily storing the streamed received content data, Stores content purchase program 221 etc. for downloading content data in the second distribution form when content data is streamed in the first distribution form and there is a request to download content data by operating the remote control 208 etc. These are read by the CPU 202, and functions according to these programs are executed by the CPU 202.

Further, the main storage device 205 further stores an index table storage area for storing the index table 222 (see FIG. 11) and a routing table storage area for storing the routing table 223 (see FIG. 6). Is provided.

[0140] Here, the OS program 217 is read and executed by the CPU 202, thereby performing functions related to input / output of the user-input remote control 208, memory management of the main storage device 205, the hard disk device 203, and the like. The basic function of the computer which is the terminal device 2 is made executable. Then, with the OS program 217 being executed by the CPU 202, the above-described stream control program 215, topology management program 216, screen control program 218, music decoder program 219, content purchase program 221 and the like are stored in the main storage device 205. Is read from and executed.

[0141] 〇S program 217, stream control program 215, topology management program

216, Screen control program 218, Music decoder program 219, Content purchase program The ram 221 or the like may be downloaded to the main storage device 205 from a server or the like connected to the network 6, for example, and after being recorded on a recording medium such as a CD-ROM, Thus, it may be read into the main storage device 205.

[0142] (About control unit 230)

The control unit 230 includes the CPU 202 and the main storage device 205 as described above, and the CPU 202 reads and executes the various programs 215 to 219, 221 stored in the main storage device 205, thereby executing the terminal device 2 Overall control, and connection means, streaming reception means, display control means, decoding means, streaming playback means, streaming relay means, identification information list reception means, identification information acquisition means, determination means, content data, which will be described later Storage control means, download processing means, message destination determination means, content holding terminal device information selection means, content holding terminal device information return means, content identification information calculation means, content registration message generation means, content registration message transmission means, message Functions as transfer means, content playback means, etc. There.

It should be noted that the CPU 202 executes the stream control program 215 as a stream receiving means, a streaming relay means, etc., and the CPU 202 executes the topology management program 216 as a connection means, etc. By executing the screen control program 218, the CPU 202 executes the content purchase program 221 as the display control means, and the CPU 202 executes the music decoder program 219 as the decoding means, streaming playback means, content playback means, etc. By executing, identification information list receiving means, identification information acquisition means, determination means, content data storage control means, download processing means, message destination determination means, content holding terminal device information selection means, content holding terminal device information return means , It functions as content identification information calculation means, content registration message generation means, content registration message transmission means, message transfer means, and the like.

[0144] (About connection methods)

The connection means transmits a connection destination introduction request to the connection management device 3 via the network 6 in order to cause the terminal device 2 to participate in the first distribution form of the content distribution system S, and then from the connection management device 3 to the network 6. To connect to the notified connection destination candidate. More specifically, the connection means transmits a registration request to the connection management device 3 via the network 6 and connects the terminal device 2 to participate in the first distribution mode of the content distribution system S. It has a function of registering to the management apparatus 3 and further transmitting a connection destination introduction request via the network 6 to request a connection destination candidate from the connection management apparatus 3. This registration request and connection destination introduction request include location information of the own terminal device 2 and the like.

[0146] 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 via the network 6, that is, the connection destination candidate terminal It has a function to receive information such as IP address and port number (hereinafter abbreviated as “connection destination candidates” including information on connection destination candidates), which is device location information.

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

[0148] (About streaming receiving means)

The streaming receiving means receives content data transmitted as a content packet from the upstream device, that is, the content distribution device 1 logically connected upstream or the terminal device 2 connected upstream by the first distribution form via the network interface 204. Streaming reception is performed, and the content data thus streamed is stored in the ring buffer area 220 sequentially. Note that the content data receiving means and the content data relay means described later can use a known streaming distribution protocol, or can use a unique dedicated protocol.

[0149] (About streaming playback means)

The streaming playback means has a function of sequentially playing back the content data stream-received from the upstream device through the network interface 204 in the first distribution form and sequentially stored in the ring buffer area 220. [0150] This streaming reproduction means realizes this function by operating the sound source chip 211 and the video chip 209, and sequentially retrieves the content data stored in the ring buffer area 220 to obtain predetermined content data. It is converted into a format (for example, Wave format) and input to the sound source chip 211 or the video chip 209, and the content is played back.

[0151] The content data converted into the predetermined content data format by the streaming playback means is stored in the audio data after the audio information is converted into the audio signal by the sound source chip 211 when the content data includes audio information. Output from speaker 21 2.

[0152] In addition, when the content data converted into the predetermined content data format by the streaming playback means includes video information, the video information is stored in the built-in display 210 under the control of the display control means described later. Is displayed.

[0153] Also, the streaming playback means determines the timing for playing back the content data based on the playback start time information included in the content data stored in the ring buffer area 220. That is, the playback means is configured to output the content data stored in the ring buffer area 220 to the built-in speaker 212 and the built-in display 210 at the playback start time.

[0154] (Display control means)

The display control means has a function of controlling the video chip 209 and the built-in display 210 to display content data and various information. That is, the display control means can control how the content video and various information are displayed on the built-in display 210.

[0155] (About streaming relay means)

The streaming relay means is configured to receive content data stream-received via the network 6 from the upstream device in the first distribution form, that is, the content distribution device 1 or the terminal device 2 connected upstream, to other downstream devices. Transfer to terminal device 2 via network 6.

[0156] (Identification information list receiving means)

The identification information list receiving means receives the identification information list transmitted from the content input device 4. It has a function to receive. The identification information list transmitted from the content input device 4 is information in which the name and content ID of content data that can be downloaded in the second distribution form are associated with each other, and the terminal device 2 has participated in the second distribution form. The content input device 4 transmits the identification information list to the content input device 4 from time to time. In addition, when a predetermined number of content data items are newly input to the content distribution device 1 or the terminal device 2, the content input device 4 transmits or notifies the updated identification information list to each terminal device 2. N

[0157] Regarding the content data reproduced by the streaming reproduction means in the first distribution form, not only by making a transmission request for the identification information list to the content input apparatus 4 when the own terminal apparatus 2 participates in the second distribution form. When a download request operation is performed, the identification information list may be requested and received from the content input device 4 by the identification information list receiving means.

[0158] (Identification information acquisition means)

The identification information acquisition means acquires the download requested content data in the second distribution form when there is a download request operation for the content data received by the streaming receiving means in the first distribution form and reproduced by the streaming playback means. Therefore, the content ID that is the identification information of the content data requested to be downloaded is acquired. That is, the identification information acquisition unit acquires the content ID that is the identification information of the content data requested for download from the identification information list received by the identification information list reception unit.

Here, “content data received by the streaming receiving means in the first distribution form and played by the streaming playback means” means that a screen as shown in FIG. 12 is displayed on the built-in display 210. In this case, the content data is limited to only the content data being played back by streaming, but when the screen shown in FIG. 13 is displayed on the built-in display 210, the content data is not limited to the content data being played back by streaming. It includes content data that was played back in the past and content data that is scheduled for playback in the future.

[0160] It should be noted that the identification information acquisition means is the content of the content data requested to be downloaded. Only the ID may be acquired from the content input device 4. In this case, the identification information acquisition unit transmits the name of the content data requested to be downloaded to the content input device 4 and acquires the content ID of the content data requested to be downloaded.

[0161] Further, the identification information acquisition means may obtain the content ID of the content data requested to be downloaded by the content identification information calculation means described later. In other words, the content ID is obtained by hashing with the hash function using the name of the content data requested for download as a keyword. By obtaining the content ID using the name of the content data requested for download in this way as a keyword, the download processing in the second distribution form in the terminal device 2 is facilitated. The name of the content that can be downloaded in the second distribution form is acquired from the content input device 4 in the form of a list, etc., and the content identification information calculation means acquires the name of the content from this list or the like. Thus, the content ID can be calculated.

[0162] (Judgment means)

The determination means determines whether or not the entire content data requested to be downloaded is stored in the ring buffer area 220.

[0163] (Content data storage control means)

When the content data storage control unit determines that the content data requested for download is stored in the S-ring buffer area 220 by the determination unit, the content data storage control unit does not download the content data in the second distribution form, and does not download the content data. The content data stored in the area 220 is stored in the content data storage area of the hard disk device 203.

[0164] (Download processing means)

The download processing means has a function of downloading the content data requested for download based on the identification information of the content data acquired by the identification information acquisition means, and the terminal device of the second distribution form, and download destination search means In addition, it is composed of down-port transmission request means and download data reception means.

[0165] The download destination search means stores the content data requested to be downloaded based on the content ID of the content data acquired by the identification information acquisition means. Search for a content holding terminal device.

[0166] The search for the content holding terminal device generates a content search message with the content ID acquired by the identification information acquisition means as the destination identification information, and the location of the terminal device having the terminal ID in the same area as the content ID is determined. Information is extracted from the routing table 223 and a content search message is transmitted to the terminal device.

Then, in response to the content search message, the location information of the content holding terminal device that holds the content data of the content ID acquired by the identification information acquisition unit is transmitted from the root terminal device.

[0168] In this way, the download destination search means searches for a content holding terminal device that holds content data requested to be downloaded.

[0169] Further, the download transmission request means requests the content holding terminal device searched by the download destination search means to transmit the content data requested for download via the network 6 (hereinafter referred to as "download transmission request"). "). This download transmission request sets the content ID of the content data corresponding to the download request with the location information of the content holding terminal device as the destination. When there are a plurality of content holding terminal devices searched by the download destination searching means, a download transmission request is made to one of the nearby content holding terminal devices.

[0170] Here, the "neighboring content holding terminal device" is a terminal device that makes a download transmission request. The content holding terminal device is connected to the DHT routing, and the terminal ID is close, the terminal device, or This means a content holding terminal device close to the physical network. In particular, if the content holding terminal device that makes a download transmission request is a physical network, a near-end, or content holding terminal device, content data can be downloaded from the content holding terminal device in a short time. it can. Note that “close to the physical network” means that the message arrival time from the terminal device making the download transmission request is short, or the number of pops from the terminal device making the download transmission request (number via the router). Means less.

[0171] Further, the download data receiving means stores the content data requested to be downloaded and stores the content data requested to be downloaded. Received via network 6. The content data transmitted from the content holding terminal device is data in a download format that is not in the streaming format as in the first distribution mode.

The content data received by the download receiving means is stored in the content data storage area (corresponding to the content data storage means) of the hard disk device 203 by the control unit 230.

[Message destination judgment means]

The message destination determination means determines whether or not the received message is addressed to its own terminal device 2 based on the destination identification information of the message received via the network 6 and the routing table. The message determined by the message destination determination means is the above-described content search message, content registration message, or the like.

[0174] Whether or not the received message is addressed to the own terminal device 2 is determined based on the routing table stored in the main storage device 205 by extracting the destination terminal ID (destination identification information) included in the message. To do. That is, when various messages are received via the network interface 204, the message destination determination means compares the destination identification information included in the received message with the terminal ID stored in the routing table 223, and then compares the message. If it is determined that the terminal ID on the routing table 223 closest to the destination identification information included in the message is the terminal ID of the own terminal apparatus 2, it is determined that the message is addressed to the own terminal apparatus 2.

[0175] (Content holding terminal information selection means)

When the content holding terminal device information selection unit determines that the message received by the message destination determination unit via the network 6 is addressed to its own terminal device 2 and is a content search message, the content search is performed from the index table 222. The location information of the content holding terminal device that holds the content data of the content ID targeted by the message is selected. If there are a plurality of pieces of location information of content holding terminal devices in the index table 222, all or some of them are selected.

(About content holding terminal device information return means)

The content holding terminal device information return means is content holding terminal device information selection means. The location information of the content holding terminal device selected by (2) is returned to the requesting terminal device via the network 6.

[0177] (About content identification information calculation means)

The content identification information calculation means calculates the content ID which is the identification information of the content data by calculating the unique information of the content data by a predetermined hash function as described above.

[0178] (About content registration message generation means)

When content data is received from the content input device 4, the received content data is stored in the hard disk device 203, which is a content data storage means. In addition, a content registration message including the terminal ID and IP address of the local terminal device is generated using the content ID calculated by the content identification information calculation means as the destination identification information.

[0179] (Content registration message transmission means)

The content registration message transmitting means transmits the content registration message generated by the content registration message generating means from the terminal device identification information stored in the routing table 223 based on the content ID of the content data stored in the hard disk device 203. Select the destination terminal device and transmit. For example, if the content ID of the content data stored in the hard disk device 203 is “1231”, and the content registration message transmission means has a routing table as shown in FIG. "Is selected as the destination terminal device, and the IP address" 21.13.21.13 "of the terminal device with the terminal ID" 1221 "is extracted. Then, the content registration message is transmitted using the IP address “21.13.21.13” as the destination terminal device. The destination identification information of this content registration message is “1231”.

[0180] (About message transfer means)

When the message destination determination means determines that the message received via the network 6 is not destined for its own terminal device, the message transfer means determines the transfer destination based on the destination identification information of the received message. The location information of the terminal device is extracted from the routing table 223, and the received message is transferred to the destination terminal device. [0181] (About decoding means)

The decoding means displays the content data transmitted from the other terminal device 2 on the display 210 and decodes it for output from the speaker 212. That is, the content data transmitted from the other terminal device 2 is encoded in a data format for streaming delivery, for example, ASF, WMA, WMV, etc., and the content data encoded in this way is encoded. Is decoded so that it can be output from display 210 or speaker 212.

[0182] (About content playback means)

The content playback means extracts and plays back the content data stored in the hard disk device 203. At this time, the control unit 230 operates the video chip 209 and the sound source chip 211 based on the stream control program 215. Content data is played back.

[0183] [4. Explanation 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. 16 is a diagram showing a schematic configuration example of the connection management device 3 in the present embodiment. The connection management device 3 is applicable to a general server computer. As shown in FIG. 16, a CPU (Central Processing Unit) 302 and a rewritable main storage device 305 that stores (stores) various programs and the like. And a hard disk device 303 for storing various data, a network interface 304 for communicating with the content distribution device 1, the content input device 4 and the terminal device 2 via the network 6, and predetermined information can be input. Peripheral device control chip 306 that controls input means such as keyboard 307 and mouse 308, and CPU 302 receives image data and writes it to the internal video memory (not shown) and displays the data written to this video memory on display 310 These various components are connected to each other via a system bus 301. It has been.

In the present embodiment, the control unit 330 is configured by the CPU 302 and the main storage device 305. The network interface 304 is connected to the network 6 via the router 10c. This router 10c corresponds to the router 10 shown in FIG. [About main memory 305]

The main storage device 305 manages the OS program 317 for providing the basic functions of the connection management device 3 as a computer, and the location information (IP addresses, port numbers, etc.) of multiple terminal devices 2. A terminal management program 318, and a topology management program 319 for constructing and managing a plurality of terminal devices in a tree-like hierarchical structure on a network in a tree-like hierarchical structure with the content distribution device at the top, A connection destination introduction program 320 for selecting a connection destination candidate in response to a connection destination introduction request transmitted from the terminal device 2 and transmitting connection destination candidate information to the terminal device 2 is stored. The function is read by the CPU 302 and executed by the CPU 302 according to these programs.

[0187] Here, the S program 317 is read and executed by the CPU 302 to perform functions related to input / output of the keyboard 307 and mouse 308, memory management of the main storage device 305, the hard disk device 303, etc. This makes it possible to execute the basic functions of the computer, which is the connection management device 3. Then, with the OS program 317 being executed by the CPU 302, the terminal management program 318, topology management program 319, connection destination introduction program 320, etc. described above are executed.

Note that the OS program 317, terminal management program 318, topology management program 319, connection destination introduction program 320, and the like may be downloaded to the main storage device 305 from, for example, a server connected to the network 6. Alternatively, it may be recorded on a recording medium such as a CD-ROM and then read into the main storage device 305 via the recording medium.

[0189] (About control unit 330)

The control unit 330 includes the CPU 302 and the main storage device 305 as described above, and the CPU 302 reads and executes the various programs 317 to 320 stored in the main storage device 305, so that the entire connection management device 3 is processed. It performs overall control and functions as connection destination introduction request receiving means, connection destination candidate selection means, connection destination candidate notification means, topology management means, terminal management means, etc., which will be described later. Further, the hard disk device 303 has a plurality of terminal devices logically connected in multiple layers in a hierarchical structure on the network 6 with the content distribution device 1 as a top. It is used as connection state information storage means for storing the connection state information of the device.

Note that the CPU 302 executes the terminal management program 318 as a terminal management unit and the like, and the CPU 302 executes the topology management program 319 as a topology management unit and the like. By executing this, it functions as a connection destination introduction request receiving means, a connection destination candidate selecting means, a connection destination candidate notifying means, and the like.

[0191] (Terminal management means)

When receiving the registration request from the terminal device 2, the terminal management means registers the IP address, etc., which is the location information of the terminal device 2 in the terminal management data base 314 for each broadcast channel. Also, when a registration request is received from the content distribution apparatus 1, the location information of the content distribution apparatus 1 is registered in the terminal management database 314 for each broadcast 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.

[0192] (About topology management means)

The topology management means includes a new topology generation means for generating a tree-like hierarchical structure based on the first distribution form generation request transmitted from the content distribution device 1, and a connection destination introduction request for the terminal device 2. It has a function as a topology change means for changing connection information of the terminal device 2 in the tree-like hierarchical structure by topology change notification such as topology participation report and connection disconnection notification. Further, the topology management means stores the connection status information of the terminal devices 2 constituting the hierarchical structure in the topology one database 315 as the connection status information storage means.

[0193] Upon receiving the first distribution form generation request from the content input device 4, the new topology generation means generates a topology table and registers it in the topology database 315. Here, the topology table is a table for storing connection state information and the like of the terminal devices 2 constituting the tree-like hierarchical structure, and is registered in the topology database 315.

[0194] The topology changing means executes a function of adding or deleting information of the terminal device 2 to or from the topology table stored in the topology database 315. The topology table is added or changed based on the topology participation report and connection disconnection notification after the connection destination introduction request from.

[0195] (About connection destination candidate selection means)

When the connection destination candidate selection means receives a connection destination introduction request via the network 6 from the terminal device 2 that newly participates in the first distribution form or participates in the new channel, the connection destination introduction of the terminal device 2 is introduced. A connection destination candidate for the request is selected from the connection state information stored in the topology database 315.

[0196] (About connection destination candidate notification means)

The connection destination candidate notifying unit has a function of notifying the connection destination candidate selected by the connection destination candidate selection unit via the network 6 to the terminal device 2 that has transmitted the connection destination introduction request. This 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 terminal device 2 of the connection destination candidate.

[0197] [5. Explanation of Configuration of Content Input Device 4]

Next, the configuration and operation of the content input device 4 will be described with reference to FIG.

FIG. 17 is a diagram showing a schematic configuration example of the content input device 4 in the present embodiment. As the content input device 4, a general server computer can be applied. As shown in FIG. 17, a CPU (Central Processing Unit) 402 and a rewritable main storage device 405 that stores (stores) various programs and the like. And a hard disk device 403 that stores various data, a network interface 404 that communicates with the content distribution device 1, the terminal device 2, and the connection management device 3 via the network 6, and predetermined information can be input. The peripheral device control chip 406 for controlling the input means such as the keyboard 407 and the mouse 408, and the image data from the CPU 402 are received and written to the internal video memory (not shown), and the data written to the video memory is displayed on the display 410. Video chip 409 for display, and these various components are connected to each other via the system bus 401. It has been.

Note that in this embodiment, the CPU 402 and the main storage device 405 constitute a control unit 430. The network interface 404 is connected to the network 6 via the router 10d. This router 10d corresponds to the router 10 shown in FIG. [0200] (About main memory 405)

The main storage device 405 includes an OS program 417 for providing basic functions of the content input device 4 as a computer, a content distribution device 1 in the first distribution mode, and a terminal device 2 in the second distribution mode. Content management program 419 for transmitting and managing content data to the content distribution device 1 and identification information that associates the content names and content IDs of the plurality of content data transmitted to the content distribution device 1 in the first distribution form The identification information list, which is a list, is generated and stored in the identification information list storage area of the hard disk device 403, or the identification information list is extracted from the identification information list storage area of the hard disk device 403, and the terminal device 2 or the content distribution device The catalog management program 418 and the like for transmission to 1 are stored, and these are stored in the CPU 402 Thus is Desa read, and functions according to the program by the CPU402 is executed.

[0201] Here, the S program 417 is read and executed by the CPU 402, so that functions related to input / output of the keyboard 407 and mouse 408, memory management of the main storage device 405, the hard disk device 403, etc. This makes it possible to execute the basic functions of the computer that is the content input device 4 of the above. Then, with the OS program 417 being executed by the CPU 402, the above-described catalog management program 418, content management program 419, etc. are executed.

[0202] The OS program 417, the catalog management program 418, the content management program 4 19 and the like may be downloaded to the main storage device 405 from a server or the like connected to the network 6, for example. After being recorded on a recording medium such as a CD-ROM, it may be read into the main storage device 405 via the recording medium.

[0203] (About control unit 430)

The control unit 430 includes the CPU 402 and the main storage device 405 as described above, and the CPU 402 reads and executes the various programs 417 to 419 stored in the main storage device 405, so that the entire content input device 4 is processed. It performs overall control and functions as content input means, identification information list generation means, identification information list transmission means, etc., which will be described later. Further, the hard disk device 403 stores a content data to be transmitted and input to the content distribution device 1 in the first distribution form and the content holding terminal device in the second distribution form. And an identification information list storage as an identification information list storage means for storing an identification information list relating to the content data storage area and content data transmitted to the content distribution device 1 (in other words, content data streamed by the content distribution device). It consists of areas.

[0204] Here, the identification information list storage unit also stores an identification information list including identification information of content data other than the content data to be streamed by the content distribution device 1. Therefore, content data other than the content data directly distributed in the broadcast form can be acquired in the second distribution form. For example, if the content data is music content, it is possible to acquire content that has been viewed in the past in the second distribution form.

It should be noted that the CPU 402 executes the catalog management program 418 as an identification information list generation means, an identification information list transmission means, etc., and the CPU 402 executes the content management program 419 as a content input means, etc. Each function

[0206] (About content input means)

The content input means transmits the content data distributed in the second distribution form to some of the terminal devices 2 among the plurality of terminal devices 2. Specifically, it operates as follows.

[0207] When a content data input instruction is given by a request from the content distribution apparatus 1 or by operation of input means such as the keyboard 407 and the mouse 408, the content input means stores the content data corresponding to the input instruction on the hard disk. Retrieve from the content data storage area of device 403.

[0208] The content data extracted from the hard disk device 403 is transmitted and input by the content input means to both the first distribution form and the second distribution form. However, the content input means may be input to the second distribution form even if the content data is not input to the first distribution form.

More specifically, the content input unit transmits the content data extracted from the hard disk device 403 to the content distribution device 1. The content data transmitted to the content distribution device 1 is streamed and distributed to each terminal device 2 in the first distribution form. [0210] Further, the content input means transmits the content data extracted from the hard disk device 403 to several terminal devices 2 in the second distribution form, and functions as a content holding terminal device. The destination terminal device 2 is randomly determined by the content input means.

[0211] (Identification information list generation means)

The identification information list generation unit updates the identification information list stored in the identification information list storage area of the hard disk device 403 when content data is input by the content input unit. That is, information that associates the content name and content ID of content data newly input by the content input means is added to the identification information list.

[0212] (About identification information list sending means)

The identification information list transmission means transmits the identification information list stored in the identification information list storage means to a plurality of terminal devices. That is, when there is an identification information list transmission request from the content distribution device 1 or the terminal device 2, the identification information list stored in the identification information list storage area of the hard disk device 403 is transmitted to the requested device.

[0213] [6. Description of Contour Outside Introduction Device 5]

Next, the configuration and operation of the contact introduction device 5 will be described with reference to FIG.

[0214] FIG. 18 is a diagram showing a schematic configuration example of the contact introduction device 5 in the present embodiment. As the contact introduction device 5, a general server computer can be applied. As shown in FIG. 18, a CPU (Central Processing Unit) 502, a rewritable main storage device 505 for storing (storing) various programs, etc. A hard disk device 503 for storing various data, a network interface 504 for communicating with the terminal device 2 via the network 6, and an input hand such as a keyboard 507 and a mouse 508 capable of inputting predetermined information. Peripheral device control chip 506 that controls the stage, and video chip 509 that receives image data from CPU 502, writes it to an internal video memory (not shown), and displays the data written to this video memory on display 510 These various components are connected to each other via a system bus 501. [0215] In the present embodiment, the CPU 502 and the main storage device 505 constitute a control unit 530. The network interface 504 is connected to the network 6 via the router 10e. This router 10e corresponds to the router 10 shown in FIG.

[About main memory 505]

In addition, the main storage device 505 includes a ○ S program 517 for providing basic functions of the contact introduction device 5 as a computer, and location information (such as IP addresses and port numbers) of the plurality of terminal devices 2. Terminal management program 518 for managing, etc., and contact destination terminal device introduction program for introducing other terminal devices 2 of the contact destination in response to a request from the terminal device 2 not participating in the second distribution form 519 etc. are stored, and these are read out by the CPU 502, and the functions according to these programs are executed by the CPU 502.

[0217] Here, the S program 517 is read and executed by the CPU 502, so that functions related to input / output of the keyboard 507 and mouse 508, memory management of the main storage device 505, the hard disk device 503, etc. This makes it possible to execute the basic functions of the computer which is the contact introduction device 5 of the above. Then, with the OS program 517 being executed by the CPU 502, the above-described terminal management program 518, contact terminal device introduction program 519, etc. are executed.

Note that the OS program 517, the terminal management program 518, the contact destination terminal device introduction program 519, etc. may be downloaded to the main storage device 505 from, for example, a server connected to the network 6. Further, it may be recorded on a recording medium such as a CD-ROM and read into the main storage device 505 via the recording medium.

[0219] (About control unit 530)

The control unit 530 includes the CPU 502 and the main storage device 505 as described above, and the CPU 502 reads and executes the various programs 517 to 519 stored in the main storage device 505, so that the contact destination introduction device 5 And functions as terminal device management means, contour destination terminal device introduction means, etc., which will be described later.

[0220] Note that the CPU 502 executes the terminal management program 518, so that the CPU 502 executes the contact destination terminal device introduction program 519 as a terminal management means or the like. Therefore, it functions as an outside contour terminal device introduction means or the like.

[0221] (About terminal management means)

When receiving the registration request for the second distribution form 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 515. 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.

[0222] (Contour outside terminal device introduction means)

When the contact destination terminal device introduction means receives a registration request for the second distribution form from the terminal device 2, the terminal device 2 that made the registration request from the terminal device 2 registered in the terminal management database 515 sends a participation message. Select the terminal device 2 to be transmitted.

[0223] The contact destination terminal device introduction means extracts the location information of the selected terminal device 2 from the terminal management database 515, and transmits it to the terminal device 2 that made the registration request.

[0224] [7. Operation of content distribution system S]

Hereinafter, detailed operations of the content distribution device 1, the terminal device 2, the connection management device 3, the content input device 4 and the contact destination introduction device 5 will be described more specifically with reference to flowcharts.

[0225] (Description of processing flow of content distribution device 1)

First, an example of a more specific operation of the content distribution apparatus 1 will be described with reference to FIG. FIG. 19 is a flowchart showing the entire processing in the content distribution apparatus 1. The following processes are executed by the control unit 130 of the content distribution apparatus 1 functioning as the above-described means.

First, as shown in FIG. 19, when the power of the content distribution apparatus 1 is turned on, in the content distribution apparatus 1, the CPU 102 initializes the access permission and the work area of the main storage device 105 and the hard disk device 103. Initialization processing such as conversion is executed (step S100), and each program 115 to 120 is set to the execution state by the CPU 102, and the function as the control unit 130 is operated. Then, the processing proceeds to step S101.

[0227] In step S101, the control unit 130 in the content distribution device 1 requests the content input device 4 for content data to be broadcast in the first distribution form, and The content data transmitted from the content input device 4 in response to the request is stored in the broadcast content storage area in the hard disk device 103.

[0228] In step S102, the control unit 130 in the content distribution apparatus 1 determines whether or not a broadcast start request or stop request is received from the broadcast operator. Here, whether a broadcast start request or stop request is received from the broadcast operator is based on whether the broadcast start operation has been performed from the input means such as the keyboard 107 or the mouse 108 or the keyboard 107 or the mouse 108. Judgment is made based on whether or not a broadcast stop operation has been performed from the input means. Here, the broadcast operator means an operator who manages content distribution according to the first distribution form and the second distribution form, but the content distribution according to the first distribution form and the second distribution form are separated from each other. It may be done by a person.

[0229] In this process, if it is determined that a broadcast start request is received from the broadcast operator (step S102: Yes), the control unit 130 divides the content data retrieved from the hard disk device 103 into predetermined volumes. The content packet is stored in the content packet, and the content packet is prepared for transmission to the terminal device 2 logically connected downstream via the network 6. On the other hand, similarly, when it is determined that a broadcast stop request has been received from the broadcast operator (step S102: Yes), the control unit 130 performs the operation for the terminal device 2 logically connected downstream. The generation of the content packet is stopped (step S103). When the process of step S103 ends, control unit 130 moves the process to step S120.

On the other hand, in step S102, when control unit 130 determines that there is no broadcast start request from the broadcast operator (step S102: NO), it moves the process to step S110.

[0231] In step S110, the control unit 130 in the content distribution apparatus 1 determines whether there is a request for opening or disconnecting a session from the terminal apparatus 2. In this process, the control unit 130 in the content distribution apparatus 1 determines whether or not a request for opening or disconnecting a session has been received from the terminal apparatus 2 via the network 6.

[0232] In this process, if the control unit 130 determines that a session establishment request has been received (step S110: YES), the control unit 130 establishes a connection with the terminal device 2 (step S111), and disconnects the session. If it is determined that the request has been received (step S110: YES), the connection with the terminal device 2 is disconnected (step S111), and the process proceeds to step S112. In other words, control The control unit 130 performs control to change and set the connection state of the terminal device 2 in response to a request from the terminal device 2.

[0233] If it is determined in step S110 that a session establishment request has been received (step S1 10: YES), the control unit 130 determines in step S112 that the terminal device 2 logically connected downstream of the content distribution device 1 is connected. To stream the content data. That is, the content packet generated in step S102 is sequentially transmitted via the network 6 to the terminal device 2 logically connected downstream. On the other hand, similarly, when it is determined that a broadcast stop request has been received from the broadcast operator (step S102: Yes), the control unit 130 connects the terminal device 2 logically connected downstream of the content distribution device 1. Stop streaming transmission of content data. That is, the transmission of the content packet generated in step S102 is stopped (step S112). When the process of step S112 ends, control unit 130 moves the process to step S120.

[0234] On the other hand, when determining in step S110 that the terminal device 2 has not requested a session establishment or disconnection (step S110: NO), the control unit 130 shifts the processing to step SI20.

[0235] In step S120, control unit 130 determines whether or not the power is off. If it is determined that the power is off (step S 120: YES), the process ends. If it is determined that the power is not off (step S120: NO), the process is repeated from step S102.

[0236] (Description of processing flow of terminal device 2)

Next, an example of a more specific operation of the terminal device 2 will be described with reference to FIGS. 20 to 26 are flowcharts showing the entire processing in the terminal device 2. The following processes are executed by the control unit 230 of the terminal device 2 functioning as the above-described units.

[0237] As shown in FIG. 20, when the power supply of the terminal device 2 becomes 0N, the CPU 202 of the terminal device 2 initializes the access permission of the main storage device 205 and the hard disk device 203, initializing the work area reservation, etc. After executing the operation and setting each program 215 to 219, 221 to the execution state by the CPU 202 and operating the function as the control unit 230 (step S200), step S201 Move processing to.

[0238] In step S201, the control unit 230 performs the participation process in the second distribution form, and then moves the process to step S202. The process of step S201 is the process of S270 to S276 in FIG. 23 and will be described in detail later.

[0239] In step S202, the control unit 230 determines whether or not there is a channel selection instruction from the user. Whether or not a channel selection instruction has been issued by the user is determined based on whether or not a channel selection instruction has been operated from input means such as the user one-input remote controller 208.

[0240] In this process, when it is determined that the channel selection instruction from the user has been received (step S202: YES), the control unit 230 provides a content stream (contents) to the upstream device in the first distribution form. A request to stop streaming data) is made via the network 6 (step S203). In other words, streaming distribution of content data to the content distribution device 1 or other terminal device 2 that is logically connected to the terminal device 2 and performs streaming distribution to the terminal device 2 in the first distribution mode. Request over network 6 to stop.

[0241] When the process of step S203 ends, control unit 230 moves the process to step S204. In step S204, the control unit 230 requests the connection management device 3 for upstream device candidates. That is, in order to participate in the hierarchical structure of the broadcast channel for which the channel selection instruction has been received from the user, the connection management apparatus 3 is selected with respect to the connection destination candidate of the upstream apparatus related to the broadcast channel for which the channel selection instruction has been issued, Request to be notified. When the process of step S204 ends, control unit 230 moves the process to step S269.

Note that in the present embodiment, a predetermined broadcast channel is selected in the initialization process of step S201. That is, it is placed in the same state as when a predetermined broadcast channel is selected by the user. Therefore, when the power of the terminal device 2 becomes ◯ N, in order to participate in the hierarchical structure of the predetermined broadcast channel, the connection management device 3 is selected and notified of the upstream device connection destination candidate for the predetermined broadcast channel. It asks you to do it. [0243] On the other hand, if it is determined in step S202 that there has been no channel selection instruction from the user (step S202: NO), the control unit 230 determines whether or not the candidate for the upstream device has been received from the connection management device 3. Determination is made (step S210). That is, it is determined whether or not the connection destination candidate of the upstream device has been notified from the connection management device 3 in response to the connection destination candidate notification request made in step S204.

[0244] If this process determines that an upstream device candidate has been received from the connection management device 3 (step S210: YES), the control unit 230 connects to the upstream device notified from the connection management device 3. After selecting an upstream device of one connection destination candidate from the destination candidates (step S211), the process proceeds to step S212.

[0245] In step S212, the control unit 230 makes a logical connection via the network 6 to the selected upstream device of the connection destination. The logical connection to the upstream device is executed by the control unit 230 making a connection request to the upstream device via the network 6.

[0246] Thereafter, in step S213, the control unit 230 requests the upstream device for streaming distribution of the content data via the network 6, and proceeds to the process of step S214.

In step S214, the control unit 230 transmits a topology participation report to the connection management device 3 via the network 6. When the process of step S214 ends, control unit 230 moves the process to step S269.

[0248] On the other hand, when it is determined in step S210 that the upstream device candidate has not been received from the connection management device 3 (step S210: NO), the control unit 230 determines whether or not the content packet has been received from the upstream device. Is determined (step S215).

[0249] In this process, if control unit 230 determines that a content packet has been received from the upstream device (step S215: YES), it extracts the content data from the content packet received from the upstream device and stores it in ring buffer area ₂₂₀ . Further, the content data is taken out and transferred to the downstream terminal device 2 as a content packet (step S216).

[0250] After that, the control unit 230 acquires and reproduces the content data stored in the ring buffer area 220 (step S217). Playback of content packets can be done with the sound source chip 211 or video This function is realized by operating the chip 209. The content packets stored in the ring buffer area 220 are sequentially extracted from the content packets at the playback time, and a predetermined content data format (for example, the Wave format is used). ) And input to the sound source chip 211 and the video chip 209 to reproduce the content. When the process of step S217 ends, control unit 230 moves the process to step S269.

On the other hand, when it is determined in step S215 that no content packet has been received from the upstream device (step S215: NO), control unit 230 determines whether or not there is a streaming distribution start Z stop request. (Step S220). Whether or not there is a streaming distribution start Z stop request depends on whether or not a streaming distribution start request transmitted from the downstream terminal apparatus 2 has been received or a streaming distribution stop transmitted from the downstream terminal apparatus 2. This is determined by whether or not a stop request has been received.

[0252] In this process, when the control unit 230 determines that there is a streaming distribution start request (step S220: YES), the control unit 230 transfers the content packet to the downstream device that has made the streaming distribution start request. Start (step S221). If the control unit 230 determines that there is a streaming distribution stop request (step S220: YES), the control unit 230 stops the transfer of the content packet to the downstream device that has made the streaming distribution stop request (step S221). ). This process is set to determine whether or not to perform the process in step S216. If it is determined that there is a streaming distribution start request, the content packet is set to be transferred to a downstream device, and a streaming distribution stop request is issued. If it is determined that the content packet has been transferred, the transfer of the content packet to the downstream apparatus is stopped. When the process of step S221 ends, control unit 230 moves the process to step S269.

[0253] On the other hand, when it is determined in step S220 that there is no streaming delivery start request Z stop request (step S220: NO), control unit 230 receives the content registration message as shown in FIG. Whether or not (step S225). Whether or not the content registration message has been received is determined by whether or not the content registration message transmitted from the content holding terminal device via the network 6 has been received by the terminal device 2 itself.

[0254] In this process, if it is determined that the content registration message has been received (step S22). 5: YES), the control unit 230 determines whether the content holding terminal device identification information, the content holding terminal device location information, and the content holding terminal device are included in the content registration message received in the index table 222 of the main storage device 205. This is performed by associating with the content ID of the content data to be held and adding it to the index table 222 (step S226).

[0255] After that, the control unit 230 determines whether or not the own terminal device 2 is a root terminal device (step S227). Whether or not the terminal device 2 is the root terminal device is determined based on the destination identification information of the received content registration message and the routing table 223.

[0256] In this process, if control unit 230 determines that self-terminal device 2 is not the root terminal device (step S227: NO), it forwards the content registration message to other terminal device ₂ based on routing table 223. (Step S228). When the process of step S228 ends, control unit 230 moves the process to step S269. On the other hand, if it is determined that self-terminal device 2 is the root terminal device (step S227: YES), control unit 230 proceeds to step S269 without performing step S228.

[0257] If it is determined in step S225 that a content registration message has not been received (step S225: NO), control unit 230 determines whether a content deletion message has been received (step S230). Whether or not a content deletion message has been received is determined by whether or not a content deletion message transmitted from the content holding terminal device has been received via the network 6.

In this process, when control unit 230 determines that a content deletion message has been received (step S230: YES), index information corresponding to the content deletion message (content ID, content holding terminal device) from index table 222. (Location, etc.) is deleted (step S231), and then the process proceeds to step S227.

[0259] If it is determined in step S230 that a content deletion message has not been received (step S230: NO), control unit 230 determines whether or not content data to be input has been received (step S235).

[0260] In this process, the control unit 230 performs content input from the content input device 4. If it is determined that data has been received (step S235: YES), input content reception processing is performed (step S236). This input content reception process is the process of S280 to S283 in FIG. 24 and will be described in detail later. When the process of step S236 ends, control unit 230 moves the process to step S269.

[0261] If it is determined in step S235 that the input content data has not been received (step S235: NO), control unit 230 determines whether there is a content purchase instruction from the user (step S240). . Whether or not there is a content purchase instruction from the user is determined by whether or not a content purchase instruction has been operated from the input means such as the remote control 208 or the like.

[0262] In response to this process, if the control unit 230 determines that a download request operation by the user, that is, a content purchase instruction has been received (step S240: YES), the content purchase process is performed (step S241). . This content purchase processing is the processing of S285 to S291 in FIG. 25 and will be described in detail later. For example, when the user performs a predetermined operation on the remote control 208 with the built-in display 210 shown in FIG. 12 or 13, the user performs a download request operation. Is determined to have been performed. When the process of step S241 ends, control unit 230 moves the process to step S269.

[0263] If it is determined in step S240 that the content purchase instruction has not been received from the user (step S240: NO), the control unit 230 determines whether there is a content download request from another terminal device 2 (step S240: NO). S245). This content download request is a request for batch transmission of the entire content data in the second distribution form, and when the terminal device 2 is a content holding terminal device or a cache device that caches the content data related to the content download request. It is determined that the content download request has been received.

[0264] If the control unit 230 determines that there is a content download request from another terminal device 2 (step S245: YES), the content data corresponding to the content download request is stored in the hard disk device 203. The extracted content data is transmitted to the other terminal device 2 that has made the content download request (step S246). ). When the process of step S246 is completed, control unit 230 moves the process to step S269.

[0265] In response to this processing, if control unit 230 determines that there is no content download request from another terminal device 2 (step S245: NO), it downloads the purchased content data as shown in FIG. It is determined whether or not (step S250). Whether or not the purchased content data has been downloaded is determined by whether or not content data has been received from the content holding terminal device that requested the download when the user requested a download request, that is, when a content purchase instruction was issued. .

[0266] If it is determined that the purchased content data has been downloaded in response to this processing (step S250: YES). The downloaded purchased content data is stored in the hard disk device 203 and stored (step S251). When the process of step S251 ends, the control unit 230 moves the process to step S269. The content data is divided into a predetermined capacity by the content holding terminal device and transmitted as a content packet, and the control unit 230 receives each content packet and stores it in the hard disk device 203.

[0267] If it is determined in step S250 that purchased content data has not been downloaded (step S250: NO), control unit 230 determines whether or not a content search message has been received (step S255). Whether or not a content search message has been received is determined based on whether or not a content search message transmitted from the request terminal device is received from the terminal device 2 via the network 6.

[0268] In this process, when control unit 230 determines that a content search message has been received (step S255: YES), it performs content search processing in step S256. This content search process is the process of S292 to S296 in FIG. 26 and will be described in detail later. When the process of step S256 ends, control unit 230 moves the process to step S269.

[0269] If it is determined in step S255 that the content search message has not been received,

(Step S255: NO), the control unit 230 determines whether or not the content holding terminal device information has been received (step S260). The content holding terminal device information is information including the location information of the content holding terminal device, and if it is determined that the content holding terminal device information has been received (step S260: YES), the control unit 230 acquires the acquired content holding terminal device. Based on the location information of the device, the content holding terminal device is requested to collectively transmit the entire content data (step S261). When the process of step S261 ends, the control unit 230 moves the process to step S269.

[0270] If it is determined in step S260 that the content holding terminal information has not been received (step S260: NO), has control unit 230 received the participation message for the second distribution form? It is determined whether or not (step S265).

[0271] In this process, when the control unit 230 determines that the participation message for the second distribution form has been received (step S265: YES), the control unit 230 transmits the possessed table information to the terminal device that has transmitted the participation message. (Step S266). That is, out of the table information of the routing table 223, table information of the lowest level among the levels not matching the destination identification information of the participation message is extracted from the routing table 223 and transmitted to the terminal device 2 that has transmitted the participation message. To do.

[0272] After that, the control unit 230 determines whether or not the terminal device 2 is a root terminal device (step S267). Whether or not the terminal device 2 is the root terminal device is determined based on the destination identification information of the received participation message and the routing table 223.

[0273] In this process, if control unit 230 determines that self-terminal device 2 is not the root terminal device (step S267: NO), it transfers the participation message to another terminal device 2 based on routing table 223. (Step S268). When the process of step S268 ends, control unit 230 moves the process to step S269. On the other hand, when it is determined that the own terminal device 2 is the root terminal device (step S267: YES), the control unit 230 moves the process to step S269 without performing the process of step S268.

[0274] In step S269, the control unit 230 determines whether or not the power source is off. If it is determined that the power source is off (step S269: YES), the control unit 230 ends the process while the power source is turned off. If it is determined that is not off (step S269: NO), the step S202 force is also repeatedly executed.

[0275] Next, the process of participating in the second distribution form in S201 will be specifically described with reference to FIG.

[0276] First, the control unit 230 of the terminal device 2 sends the contact destination introduction device 5 via the network 6. Request contact information (step S270). In response to the request for the contact destination information, the contact destination information transmitted from the contact destination introduction device 5 via the network 6 is received via the network interface 204 (step S271).

[0277] The received contact destination information includes the location information of the terminal device of the contact destination, and the control unit 230 sends a participation message to the contact destination terminal device included in the received contact destination information. Transmit via network 6 (step S272). This participation message uses the identification information of the terminal device as destination identification information.

[0278] The participation message transmitted in this way is sequentially transferred from the terminal device 2 as the contact destination, and reaches the terminal device 2 at a position where it cannot be transferred. Then, table information for each level is received from the plurality of terminal devices that have received the participation message (step S273).

Next, the control unit 230 generates a routing table based on the plurality of table information received in this way (step S274).

[0280] After that, the control unit 230 requests the identification information list from the content input device 4 via the network 6 (step S275). In response to this request, when the identification information list is transmitted from the content input device 4, the control unit 230 receives it and stores it in the hard disk device 203 (step S276).

[0281] As described above, the terminal device 2 is configured to participate in the second distribution form when the power is turned on, so that the content can be transmitted and received between the plurality of terminal apparatuses 2 in the second distribution form. It has become.

[0282] Next, the input content reception process in S236 will be specifically described with reference to FIG.

First, control unit 230 of terminal device 2 stores and stores the input content data received in step S235 in the content data storage area of hard disk device 203 (step S280).

[0284] After that, the control unit 230 determines whether or not the own terminal device 2 is a root terminal device (step S281). Whether or not the terminal device 2 is the root terminal device is determined by calculating the content name of the received content data using a predetermined hash function and determining whether or not the terminal device having the content ID is its own terminal device. The [0285] In this process, when the control unit 230 determines that the own terminal device 2 is not a root terminal device (step S281: NO), the control unit 230 sends another content registration message via the network 6 based on the routing table 223. Transmit to terminal device 2 (step S 283). On the other hand, if it is determined that own terminal device 2 is the root terminal device (step S 281: YES), control unit 230 adds the content ID and the location information of the own terminal device to index table 222 and registers them ( Step S282).

[0286] Next, the content purchase processing in S241 will be specifically described with reference to FIG.

[0287] First, the control unit 230 of the terminal device 2 obtains a content ID to be purchased from the identification information list (step S285). That is, the content ID related to the content data determined to have been given the content purchase instruction from the user in step S240 is acquired from the identification information list acquired from the content input device 4.

[0288] Next, the control unit 230 determines whether or not a complete version of the purchased content data exists in the ring buffer area 220 (step S286). Whether or not a full version of purchased content data exists is determined by whether or not the entire content data determined to have been instructed to purchase content by the user in step S240 is stored in the ring buffer area 220. To do. Note that the content data currently being viewed in the broadcast format is not entirely stored in the ring buffer area 220, and the determination in step S286 is YES for content data that has already been viewed in the broadcast format. Thus, it is limited to those stored in the ring buffer area 220.

[0289] In this process, when it is determined that the complete version of the purchased content data exists in the ring buffer area 220 (step S286: YES), the control unit 230 stores the purchased content data in the content data storage of the hard disk device 203. Store in the area (step S287). Since the content data stored in the ring buffer area 220 is content data for streaming playback, the content data stored in the ring buffer area 220 is converted into a purchased content format (download format) in the process of step S287. After that, it is stored in the content data storage area of the hard disk device 203. On the other hand, when it is determined in step S286 that the complete version of the purchased content data does not exist in the ring buffer area 220 (step S286: NO), the control unit 230 has the content ID in the index table 222. Whether or not (step S288).

[0291] In this process, when it is determined that the content ID exists in the index table 222 (step S288: YES), the control unit 230 acquires the location information of the content holding terminal device from the index table 222 (step S289). ) And the process proceeds to step S290.

[0292] In step S290, control unit 230 transmits a content transmission request to the location information of the content holding terminal device acquired from index table 222. That is, the control unit 230 makes a download transmission request to the content holding terminal device.

[0293] When it is determined that the content ID does not exist in the index table 222 (step S2 88: NO), the control unit 230 transmits a content search message to the next terminal device via the network 6 (step S2 88: NO). S291). That is, the control unit 230 transmits a content search message to another terminal device 2 via the network 6 based on the routing tape node 223. The control unit 230 acquires the location information of the content holding terminal device that is transmitted in response to the content search message, and requests the content holding terminal device to transmit the content data that contributes to the download request.

[0294] Next, the content search processing in S256 will be specifically described with reference to FIG.

First, the control unit 230 of the terminal device 2 acquires the content search message power content ID received in step S255 (step S292).

Next, control unit 230 determines whether or not the content ID acquired from the content search message exists in index table 222 (step S293).

[0297] In this process, when the control unit 230 determines that the content ID acquired from the content search message exists in the index table 222 (step S293: YES), the location of the content holding terminal device is determined from the index table 222. Get information (step

S294), the process proceeds to step S295.

[0298] In step S295, the control unit 230 acquires the code acquired from the index table 222. The location information of the content holding terminal device is transmitted to the requesting terminal device via the network 6.

On the other hand, when it is determined in step S293 that the content ID acquired from the content search message does not exist in the index table 222 (step S293: NO), the control unit 230 performs the following via the network 6. The message is transferred to the terminal device (step S296). That is, the control unit 230 transfers the content search message to another terminal device 2 via the network 6 based on the routing table 223.

[0300] As described above, the user of the terminal device 2 can download the content in the P2P grid type distribution form, which is the second distribution form, while viewing the content streamed from the content distribution apparatus in the broadcast form. Therefore, the load on the first distribution form that is a broadcast form, that is, the load on the content distribution apparatus and the network can be reduced.

[0301] Therefore, it is possible to provide a content distribution system that purchases content while viewing the content without increasing the performance of the content distribution device or the network at a great expense. In addition, since the distribution form for viewing and the distribution form for download are different, the influence on the distribution form for viewing by download purchase processing can be suppressed, and the download time of content can be shortened. It becomes possible.

[0302] Further, the terminal device 2 in the present embodiment temporarily caches content data distributed in a broadcast format in a ring buffer area, and the content data to be purchased is stored in the ring buffer area. Sometimes the content data stored in the ring buffer area can be purchased.

[0303] Therefore, the content data purchase process can be shortened compared to newly acquiring content data in the P2P grid type distribution form. By increasing the capacity of the ring buffer area, it is possible to cache a large amount of content data distributed in broadcast form, so download time for users who often download content data after viewing it. The effect of shortening is great.

[0304] In addition, the terminal device 2 in the present embodiment copies a list of content data identification information necessary for downloading content data in the P2P grid distribution mode. Since it is acquired from the content input device 4, it is possible to reduce the load on the network and the content input device 4 without having to acquire the identification information of the content data to be downloaded to the content input device 4 every time the content download process is performed. Download process time can be reduced.

[0305] Also, since the first distribution form is a broadcast form with a hierarchical structure such as a tree shape or a chain shape, the content distribution device 1 directly transmits content data to all the terminal devices 2 participating in the content distribution system. It is possible to further reduce the load on the content distribution apparatus 1 and the network that do not require distribution.

[0306] (Description of processing flow of connection management device 3)

Next, an example of a more specific operation of the connection management device 3 will be described with reference to FIG. FIG. 27 is a flowchart showing the entire processing in the connection management device 3. The following processes are executed by the control unit 330 of the connection management device 3 functioning as the above-described means.

[0307] When the power of the connection management device 3 is turned on, the CPU 302 of the connection management device 3 executes an initial setting operation such as initialization of access permission and work area reservation of the main storage device 305 and the hard disk device 303. Each program 317 to 320 is put into an execution state by the CPU 302 and the function as the control unit 330 is operated (step S300), and then the process proceeds to step S301.

In step S301, control unit 330 determines whether or not there is a participation request from terminal device 2. In this process, the control unit 330 determines whether or not a request for participation in the first distribution form from the terminal device 2 has been received via the network 6. The participation request from the terminal device 2 includes broadcast channel information that the terminal device 2 wants to participate in the first distribution form.

[0309] In this process, when control unit 330 determines that a request for participation in the first distribution form has been received from terminal device 2 (step S301: YES), location of terminal device 2 included in the received participation request is determined. Information is registered in the terminal management database 314 of the hard disk device (step S302).

[0310] On the other hand, if it is determined in step S301 that the request for participation in the first distribution form has not been received from terminal device 2 (step S301: NO), control unit 330 determines that content distribution device 1 It is determined whether or not a force registration request has been received (step S310).

[0311] If it is determined in step S310 that a registration request from content distribution apparatus 1 has been received (step S310: YES), control unit 330 obtains location information of content distribution apparatus 1 included in the received registration request. Register in the terminal management database 314 (step S311).

[0312] Next, the control unit 330 registers information on the new broadcast channel in the topology database 315. That is, a topology table of a new broadcast channel is generated in the topology database 315 (step S312).

[0313] If it is determined in step S310 that the registration request from content distribution apparatus 1 has not been received (step S310: NO), control unit 330 receives a connection destination introduction request from terminal apparatus 2 via network 6. It is determined whether or not (step S320).

[0314] If it is determined in step S320 that the connection destination introduction request has been received from the terminal device 2 via the network 6 (step S320: YES), the control unit 330 changes the connection destination introduction request from the topology database 315. The terminal device 2 or the content distribution device 1 that is a connection destination candidate for the active broadcast channel is selected (step S 321).

[0315] The control unit 330 of the connection management device 3 sends back the connection destination candidate selected in this way to the terminal device 2 that has made the connection destination introduction request, and notifies it via the network 6 (step S322).

[0316] If it is determined in step S320 that the connection destination introduction request has not been received from terminal device 2 (step S320: NO), control unit 330 determines whether or not a topology participation report has been received from terminal device 2. (Step S330). Whether or not a topology participation report has been received from the terminal device 2 is determined by whether or not a topology participation report has been received from the terminal device 2 via the network 6.

[0317] If it is determined in step S330 that there is a topology participation report from the terminal device 2 (step S330: YES), the control unit 330 extracts the location information of the terminal device 2 included in the topology participation report, and the topology database 315 Is updated (step S3331). That is, the control unit 330 registers the topology change in the topology database 315.

[0318] When the processing of steps S302, S312, S322, and S331 is completed, the process proceeds to step S330. However, when it is determined that the topology participation report has not been received from the terminal device 2 (step S330: N0), the control unit 330 determines whether or not the service termination operation of the connection management device 3 has been performed. (Step S340). If it is determined that the service termination operation has not been performed (S340: NO), the processing from step S301 is repeated, and if it is determined that the service termination operation of the connection management device 3 has been performed (step S340: YES), The process ends.

[0319] (Description of processing flow of content input device 4)

Next, an example of a more specific operation of the content input device 4 will be described with reference to FIG. FIG. 28 is a flowchart showing the entire processing in the content input device 4. Note that the following processes are executed by the control unit 430 of the content input device 4 as a means described above.

[0320] When the power of the content input device 4 becomes 0N, the CPU 402 of the content input device 4 executes initial setting operations such as initialization of access permission and work area reservation of the main storage device 405 and the hard disk device 403, Each program 417 to 419 is set to the execution state by the CPU 402, the function as the control unit 430 is operated (step S400), and the processing is moved to step S401.

[0321] In step S401, control unit 430 determines whether or not there is a content input instruction (step S401). Here, whether or not there is a content input instruction is determined by whether the control unit 430 determines whether or not a content input operation has been performed from an input unit such as a keyboard 407 or a mouse 408 or from the content distribution apparatus 1 in step S410 described later. Judgment is made based on whether or not a content data transmission request is received. This content input instruction is performed by specifying content data by the name of the content.

[0322] In this process, when it is determined that there is a content input instruction (step S401: YES), control unit 430 stores content ID corresponding to the content data specified by the content input instruction in hard disk device ₄₀₃ . After storing in the management table (step S402), the process proceeds to step S403. The management table stores a plurality of content data stored in the hard disk device 403 and content IDs in association with each other. Further, for each content data stored in the hard disk device 403, the content distribution device 1 and the content Whether it is input to the holding terminal device Is stored in association with each content. The flag includes an unfilled flag (flag value is “0”) and a loaded flag (flag value is “1”).

In step S403, control unit 430 updates the identification information list, and moves the process to step S404. The identification information list is updated by additionally storing the content ID and the content name corresponding to the content data specified by the content input instruction in the identification information list stored in the hard disk device 403.

[0324] In step S404, the control unit 430 becomes a content holding terminal device for the content data specified by the content input instruction so that the content data specified by the content input instruction can be distributed by the second distribution form. Decide at least one terminal device 2 at random. The control unit 430 transmits the content data specified by the content input instruction via the network 6 to the terminal device 2 determined as described above.

[0325] On the other hand, when it is determined in step S401 that there is no content input instruction (step S401: NO), control unit 430 determines whether or not a content data transmission request has been received from content distribution device 1. . The content data transmission request is made by specifying the content data by the content name or the like.

[0326] In this process, if it is determined that a content data transmission request is received from content distribution device 1 (step S410: YES), control unit 430 transmits content data corresponding to the content data transmission request to the hard disk device. It is taken out from 403 and transmitted to the content distribution apparatus 1 via the network 6 (step S411).

[0327] If it is determined in step S410 that there is no content data transmission request from content distribution device 1 (step S410: NO), control unit 430 receives an identification information list transmission request from terminal device 2. It is determined whether or not it is hot (step S420).

[0328] In this process, if it is determined that the terminal device 2 has received a transmission request for the identification information list

(Step S420: YES), control unit 430 takes out the identification information list stored in hard disk device 403. The control unit 430 transmits this identification information list to the terminal device that has requested transmission of the identification information list via the network 6 (step S421).

[0329] The processing power of steps S404, S411, and S421 When the processing is completed, the process returns to step S420. When it is determined that the topology participation report is not received from the terminal device 2 (step S420: NO), the control unit 430 determines whether or not the service termination operation of the content input device 4 has been performed (step S430). ). If it is determined that the service termination operation has been performed (S430: NO), the processing from step S401 is repeated, and if it is determined that the service termination operation of the content input device 4 has been performed (step S430: YES), the process is terminated.

As described above, the content input device 4 is the content distribution device in the first distribution form.

Content data is sent to and input from the terminal device 2 in the second distribution form 1 and the content to be input to the first distribution form and the second distribution form in the content distribution system S by the content input apparatus 4 Data can be managed. In addition, the identification information list is generated and updated, and is transmitted in response to a request from the terminal device 2, whereby the terminal device 2 transmits the content data distributed in the first distribution form to the second distribution form. Make it easy to get in.

[0331] Further, the content input device 4 can store an identification information list including identification information of content data other than the content data to be streamed by the content distribution device 1, so that the content directly distributed in the broadcast form Content data other than data can be acquired in the P2P grid distribution format. For example, if the content data is music content, it is possible to acquire music content that has been viewed in the past in a P2P grid distribution format.

[0332] The generation and update of the identification information list may be performed for each broadcast channel. In this case, the control unit 130 of the content distribution device 1 transmits a transmission request for content data including broadcast channel information to the content input device 4. The control unit 430 of the content input device creates an identification information list for each broadcast channel based on the broadcast channel information included in the content data transmission request. Since an identification information list can be generated for each broadcast channel in this way, it is possible to reduce the burden on the content input device 4 and the network by simply transmitting the minimum necessary identification information list to the terminal device. Can do.

[0333] In addition, the generation and update of the identification information list is such that information regarding content data that has passed a predetermined period from the time when it was input to the content distribution apparatus 1 is deleted from the identification information list. It may be. In this case, the control unit 430 of the content input device 4 stores the added date and time for each piece of information related to the content data added to the identification information list. After a specified period (for example, 10 days) has elapsed from the date and time of addition, it is deleted from the identification information list. By doing so, the data size of the identification information list can be reduced, and the load on the content input device 4 and the network can be reduced.

[0334] Further, the generation and update of the identification information list may be performed in response to a request from the content distribution apparatus 1. In this case, the content distribution device 1 issues a request for generating or updating the identification information list to the content input device 4, and the content input device 4 generates or updates the identification information list in response to this request. The identification information list generated and updated is transmitted to the content distribution apparatus 1.

[0335] (Explanation of processing flow of contact introduction device 5)

Next, an example of a more specific operation of the contact introduction device 5 will be described with reference to FIG. FIG. 29 is a flowchart showing the entire processing in the contact introduction device 5. The following processes are executed by the control unit 530 of the contact introduction device 5 functioning as the above-described means.

[0336] When the contact introduction device 5 is powered on, the CPU 502 of the contact introduction device 5 performs initial setting operations such as initializing access permission and work area reservation for the main storage device 505 and hard disk device 503. Then, each program 517 to 519 is put into an execution state by the CPU 502, the function as the control unit 530 is operated (step S500), and the processing is moved to step S501.

[0337] In step S501, control unit 530 determines whether or not there is a contact introduction request. Here, whether or not there is a contact destination introduction request is determined based on whether or not control unit 530 has received a contact destination introduction request transmitted from the terminal device via network 6.

[0338] In this process, when it is determined that there is a contact introduction request (step S501: YES), the control unit 530 sends a contact in the second distribution form to the terminal device that has made the contact introduction request. The destination candidate is returned (step S502).

[0339] When the processing in step S502 is completed, or in step S501, the contact information is introduced. When it is determined that there is no request for intervention (step S501: NO), the control unit 530 determines whether an operation for ending the service of the contact introduction device 5 has been performed (step S503). If it is determined that the service termination operation has not been performed (S503: NO), the processing from step S501 is repeated, and if it is determined that the service termination operation of the contact introduction device 5 has been performed (S503: YES), The process ends.

[0340] [8. Modification 1]

In the above embodiment, the identification information list is transmitted to the terminal device 2 from the content input device 4. However, in the present modification 1, a content distribution device is added by adding the following configuration to the above embodiment. Send from 1. Note that the content input device 4 does not generate and update the identification information list, and the terminal device 2 does not send an identification list transmission request to the content input device 4.

[0341] The control unit 130 of the content distribution device 1 transmits the identification information of the content data using the first distribution mode. The content data identification information may be transmitted by including it in the content data or separately from the content data. This process functions as an identification information transmission unit when the CPU 102 reads out and executes the content management program 121 from the main storage device 105. In other words, the identification information transmitting means transmits the identification information of the content data to be streamed by the distribution means.

[0342] Also, the terminal device 2 acquires the identification information of the content data requested to be downloaded, using the identification information of the content data transmitted from the content distribution device 1. This process functions as identification information receiving means by the CPU 202 reading the content purchase program 221 from the main storage device 205 and executing it. In other words, the identification information receiving means receives the identification information of the content data transmitted from the content distribution device 1. The identification information acquisition unit acquires the identification information of the content data requested to be downloaded from the identification information of the content data received by the identification information receiving unit.

[0343] In this way, content data identification information necessary for downloading content data in the P2P grid distribution form is transmitted from the content distribution device 1 to the terminal device 2. Sent. Therefore, since the terminal device 2 does not need to request and acquire the identification information of the content data to be downloaded from the content input device 4 or the like, the processing in the content input device can be reduced. In addition, the identification information of the content data is included in the header of the content packet to be streamed and transmitted from the content distribution device.

[0344] [9. Variation 2]

In the above-described embodiment, the location terminal content is transmitted to the request terminal device, and the request terminal device downloads and acquires the content data from the content holding terminal device. The root terminal device may request the content holding terminal device to transmit the content data to the requesting terminal device.

In this case, as shown in FIG. 30, root terminal device 2Z takes out location information of content holding terminal device 2Y that holds the content data requested from requesting terminal device 2X from index table 222. Then, based on the location information of the content holding terminal device 2Y, a transmission request for content data including the location information of the request terminal device 2X is transmitted to the content holding terminal device 2Y. Upon receiving the content data transmission request, the content holding terminal device 2Y transmits the content data corresponding to the content data transmission request to the location information of the request terminal device 2X included in the content data transmission request. It will be.

That is, when receiving the content search message from the request terminal device 2X as the root terminal device 2Z, the control unit 230 of the terminal device 2 replaces the function of the content holding terminal device information return means with the content holding terminal device. It functions as a content data transmission requesting means for transmitting a content data transmission request including the location information of the request terminal apparatus 2X with the location information of the content holding terminal apparatus 2Y selected by the information selection means as a destination.

Note that the request terminal apparatus 2X transmits a search message by the download destination search means, and the download data reception means receives content data corresponding to the search message from the content holding terminal apparatus 2Y. [0348] In this way, the second distribution form may be configured such that the root terminal device requests the content holding terminal device to transmit the content data to the request terminal device.

[0349] [10. Other variations]

In the above embodiment, when each terminal device 2 participates in the content distribution system S, the terminal device 2 participates in the second distribution form at the same time as the first distribution form. You may be allowed to participate in the second distribution form when requested. By doing so, it is possible to reduce the load in the terminal device 2 and the second distribution mode.

[0350] Also, the tree form hierarchical structure has been described as an example of the broadcast form of the first distribution form, but the present invention is not limited to this, and a server-client type broadcast form may be used.

[0351] In addition, the second delivery form has been described using the Pastry-type content delivery system as an example. The present invention is not limited to this, and content such as kademlia-type, chord-type, Viceroy-type, CAN-type, etc., with different message transfer methods. The present invention can also be applied to a distribution system.

Claims

The scope of the claims

[1] A first distribution form in which content data is streamed and distributed from a content distribution apparatus to a terminal apparatus in a broadcast form, and the content based on a content data download request from one terminal apparatus between the plurality of terminal apparatuses. A content distribution system having a second distribution mode in which another terminal device holding data distributes the content data,

The terminal device

Streaming receiving means for streaming receiving the content data streamed from the content distribution device;

A ring buffer area for temporarily storing content data received by the streaming receiving means;

Streaming playback means for streaming playback of content data stored in the ring buffer area;

When there is a download request operation on the content data played back by the streaming playback means, the identification for acquiring the identification information of the content data is acquired in order to acquire the content data requested for download in the second delivery form. Information acquisition means;

Download processing means for downloading the content data requested to be downloaded from the terminal device of the second distribution form based on the identification information of the content data acquired by the identification information acquiring means;

Content data storage means for storing the content data downloaded by the download processing means;

A system with content.

[2] The first distribution form is managed by a connection management device so that a plurality of terminal devices are logically connected in a hierarchical structure on a network with the content distribution device at the top, from the content distribution device. The content data to be transmitted is a broadcast form in which streaming is sequentially delivered from the upstream terminal device of the hierarchical structure to the downstream terminal device by the relay function of the terminal device, The content distribution device includes:

Content data distribution means for streaming distribution of the content data via the network;

The connection management device includes:

Connection state information storing means for storing connection state information of the terminal device constituting the hierarchical structure; and

A connection destination candidate selection unit that selects a connection destination candidate from the connection state information stored in the connection state information storage unit when a connection destination introduction request is received from the terminal device via the network;

Notification means for notifying the terminal device that has transmitted the connection destination introduction request via the network of the connection destination candidate selected by the connection destination candidate selection means;

The terminal device

A connection means for transmitting the connection destination introduction request to the connection management device via the network, and then connecting to the connection destination candidate notified from the connection management device and participating in the first distribution form; ,

Receiving a relay request for the content data from another terminal device, and streaming relay means for streaming transfer the received content data to the terminal device that has made the relay request,

The streaming receiving means receives the content data from the content distribution device via the connection destination candidate connected via the network.

The content distribution system according to claim 1, wherein:

The terminal device

Determining means for determining whether or not the entire content data requested to be downloaded is stored in the ring buffer area;

If it is determined by the determination means that the entire content data requested to be downloaded is stored in the ring buffer area, the content data is not downloaded in the second distribution form, but is stored in the ring buffer area. ing Content data storage control means for storing content data in the content data storage means

The content distribution system according to claim 1 or claim 2, wherein

[4] Content input means for transmitting content data distributed in the second distribution mode to a part of the plurality of terminal devices;

Identification information list storage means for storing an identification information list including a plurality of pieces of identification information of content data to be streamed by the content distribution device;

An identification information list transmission unit that transmits the identification information list stored in the identification information list storage unit to the plurality of terminal devices, and the terminal device includes:

An identification information list receiving means for receiving an identification information list transmitted from the content input device;

The identification information acquisition means includes

The identification information of the content data requested for download is acquired from the identification information list received by the identification information list receiving means.

The content distribution system according to any one of claims 1 to 3, wherein:

[5] The identification information list storage unit stores an identification information list including identification information of content data other than content data to be streamed by the content distribution device.

The content distribution system according to claim 4, wherein

[6] The content distribution device includes:

Identification information transmitting means for transmitting identification information of content data to be streamed by the streaming distribution means;

The terminal device

The content distribution device has identification information receiving means for receiving identification information of the content data to be transmitted,

The identification information acquisition means includes

From the identification information of the content data received by the identification information receiving means Acquire identification information of content data requested for download

The content distribution system according to any one of claims 1 to 3, wherein:

[7] A first distribution form in which content data is streamed and distributed from a content distribution apparatus to a terminal apparatus in a broadcast form, and the content based on a content data download request from one terminal apparatus between the plurality of terminal apparatuses. A terminal device in a content distribution system having a second distribution mode in which another terminal device holding data distributes the content data,

A terminal device.

[8] The first distribution form is managed by a connection management device so that a plurality of terminal devices are logically connected in a hierarchical structure on a network with the content distribution device at the top, and the content distribution device capability is The content data to be transmitted is a broadcast form in which streaming is sequentially delivered from the upstream terminal device of the hierarchical structure to the downstream terminal device by the relay function of the terminal device, The terminal device

The terminal device according to claim 7.

[9] Judgment means for judging whether or not the entire content data requested to be downloaded is stored in the ring buffer area;

If the determination means determines that the entire content data requested to be downloaded is stored in the ring buffer area, the content data is not downloaded in the ring buffer area according to the second distribution form. Content data storage control means for storing content data in the content data storage means

The terminal device according to claim 7 or 8, wherein

[10] Identification including a plurality of pieces of identification information of content data to be transmitted in the second distribution form to a part of the plurality of terminal devices and streamed by the content distribution device An identification information list receiving means for receiving the identification information list from a content input device that transmits an information list to the plurality of terminal devices;

The identification information acquisition means includes

The terminal device according to any one of claims 7 to 9, wherein:

[11] The identification information list is streamed by the content distribution device. Includes identification information for content data other than numeric data

The terminal device according to claim 10.

[12] having identification information receiving means for receiving identification information of the content data transmitted from the content distribution device,

The identification information acquisition means includes

The identification information of the content data requested to be downloaded is acquired from the identification information of the content data received by the identification information receiving means.

The terminal device according to any one of claims 7 to 9, wherein:

[13] A recording medium in which a program for causing a computer to function as each means in the terminal device according to any one of claims 7 to 12 is recorded in a computer-readable manner.

[14] A first distribution form in which content data is streamed and distributed from a content distribution apparatus to a terminal apparatus in a broadcast form, and the content based on a content data download request from one terminal apparatus between the plurality of terminal apparatuses. A content distribution method in a content distribution system having a second distribution mode in which another terminal device holding data distributes the content data,

A distribution step in which the distribution device performs streaming distribution of the content data; and a step in which the terminal device performs streaming reception of the content data to be distributed through the distribution device via the network;

The terminal device temporarily storing the streaming-received content data in a ring buffer area; and

The terminal device streaming and reproducing the content data stored in the ring buffer area;

When the terminal device performs a download request operation on the content data to be streamed, the identification information of the content data is acquired in order to acquire the content data requested for download in the second distribution form. Acquiring the content data requested to be downloaded based on the identification information of the acquired content data. Loading step;

The terminal device storing the downloaded data in content data storage means;

A content distribution method comprising: