WO2004079580A1

WO2004079580A1 - Data distribution method and data distribution system

Info

Publication number: WO2004079580A1
Application number: PCT/JP2003/002558
Authority: WO
Inventors: Hideomi Shiinoki; Hiroyuki Kojima
Original assignee: Fujitsu Limited
Priority date: 2003-03-05
Filing date: 2003-03-05
Publication date: 2004-09-16

Abstract

A data distribution method and a data distribution system for performing streaming distribution. When a client requests a streaming server connected via a network to perform data streaming distribution and a distribution destination management table for registering the distribution destination of the data contains at least one distribution destination of the data, the streaming server instructs one of the distribution destinations of the data to streaming-distribute the data to the client. One of the distribution destinations of the data which has received the instruction becomes a distribution origin and streaming-distributes the data to the client.

Description

Specification

Data distribution method and data distribution system

The present invention relates to a data distribution method and a data distribution system, and more particularly to a data distribution method and a data distribution system for performing streaming distribution. Background art

2. Description of the Related Art Streaming distribution has been known as a method for distributing large volumes of data such as multimedia contents via networks and networks. In streaming distribution, for example, video content managed by a video 'on' demand (V0D) server is distributed via a network in response to a request from a client, and the client downloads all the video content before Instead of playing, it can be played in real time while receiving.

In this way, in the V0D system, when a client wants to watch the video content they want to watch, they request the V0D server via the network and receive streaming streaming from the V0D server, so that the video content can be viewed at any time. it can.

This is because the conventional V0D server has a video content management function and a distribution function, and can stream the content for each distribution request from the client. Therefore, depending on the processing capacity of the V0D server, even if multiple clients request the same video content at the same time, all requesting clients could see the same video content.

Since the request from the client is at an arbitrary timing, the streaming delivery from the V0D server to the client is usually performed by unicast.

It is also possible to stream the real-time video from a server that distributes the real-time video or hardware dedicated to encoding that distributes the real-time stream (hereinafter referred to as a live server).

For such live servers, streaming distribution by Although it is possible to transmit the same real-time video to many clients at the same time, it is desirable to perform multicasting because the occupied network bandwidth increases in proportion to the number of clients. However, in order to perform multicasting, the network equipment had to be compatible with multicasting.

Also, there has been proposed a video-on-demand system that combines the above-mentioned V0D system and multicast by a live server (for example, see Patent Document 1). This is because when providing image information and voice information of the server via the ATM switching network, the service information requested by subscriber A is transmitted from the server in order to reduce the bandwidth required for the ATM connection. If the server receives a request to receive the same service from another subscriber B by the time transmission starts to subscriber A, a multi-point ATM path for the same service information is sent before the transmission start time of the service information. Connect.

(Patent Document 1)

Japanese Unexamined Patent Publication No. Hei 8—2 2 8 3 3 4 (Summary, Figure 1)

In recent years, demand for high-quality video distribution within the intranet has been increasing due to the promotion of regional intranet development projects. In addition, with the spread of high-speed networks represented by ADSL, large-capacity video contents of several Mbps have been distributed on the Internet.

Also, with the spread of personal computers and ADSL, the demand for streaming distribution of such large-volume data is expected to increase further in the future.

In a live server that performs conventional V0D server tunics, for example, when simultaneously delivering 1 Mbps video content to 10 clients, it occupies a 10 Mbps network bandwidth. For this reason, it was necessary to expand the bandwidth of the network centered on live servers that perform V0D server nicycasts.

In addition, it is necessary to limit the number of simultaneous distributions depending on the processing performance of the server machine. For this reason, for example, in the case of a V0D server, measures have been taken to distribute the server load by arranging a plurality of V0D servers. Was.

If a data bucket is lost due to network load or server machine load, The video cannot be played smoothly during the playback of the video content. This is a fatal problem for streaming streaming systems.

Such a problem is caused by the distribution processing being concentrated on the V0D server and the live server (hereinafter, these may be collectively referred to as a streaming server). Also, increasing the network speed and increasing the number of streaming servers that can be considered as a solution to this problem is costly.

Accordingly, an object of the present invention is to alleviate the concentration of distribution processing on a streaming server in a data distribution method and a data distribution system for performing streaming distribution. Disclosure of the invention

[1] In order to achieve the above object, in the data transmission method according to the present invention, a first step in which a client requests data streaming distribution to a streaming server connected via a network When at least one distribution destination of the data is registered in the distribution destination management table, the streaming server streams the data to the client to any one of the distribution destinations of the data. A second step of instructing to distribute, and a third step of streaming one of the data to the client when one of the distribution destinations of the data is a distribution source. .

That is, in the data distribution method according to the present invention, first, in the first step, the client requests the streaming server connected via the network to perform the data streaming distribution in the same manner as in the past. I do.

Next, in the second step, when at least one distribution destination of the data is registered in the distribution destination management table for registering the distribution destination of the data, the data is already stored in at least one distribution destination. Has already been delivered to

Instruct one of the distribution destinations of the data to stream the data to the client.

Further, in the third step, in response to the second step, one of the distribution destinations of the data instructed becomes the distribution source, and the data is transmitted to the client. Streaming distribution.

As a result, for data that the streaming server has already streamed to one of the clients, the streaming server does not directly deliver the data in response to a delivery request from another client. One of the distribution destinations of the data registered in the distribution destination management table can be the distribution source to distribute the data to the client, thereby alleviating the concentration of the distribution processing to the streaming server. Becomes possible.

[2] Also, in the data distribution method described above, instead of the second step, the streaming server may request the client to distribute the data to any one of the distribution destinations of the data. And a fifth step in which the client requests any one of the data distribution destinations to distribute the data.

That is, as in the second step described above, instead of instructing any one of the distribution destinations of the data to distribute the data to the client, the streaming server performs the fourth step. In the step, the streaming server instructs the client to request distribution of the data from any one of the distribution destinations of the data, and the client receiving the instruction performs the fifth step. Requesting one of the distribution destinations of the data to distribute the data.

Accordingly, in the third step, in response to the fifth step, one of the distribution destinations of the data requested by the client becomes a distribution source, and the data is transmitted to the client. Streaming

As a result, for the data that the streaming server has already streamed to one of the clients, the streaming server itself does not directly distribute the data in response to a delivery request from another client. Any one of the distribution destinations of the data registered in the distribution destination management table becomes a distribution source and can distribute the data to the client, which can reduce concentration of distribution processing to the streaming server. become.

[3] Further, in the above data distribution method, the streaming server distributes the data to another client between the first step and the second step. A sixth step of checking whether or not the client has a distribution function to perform, and a seventh step in which the streaming server installs a program of the distribution function in the client when the client does not have the distribution function. And may further include:

That is, in the sixth step executed between the first step and the second step, it is determined whether or not the client has a distribution function necessary for streaming distribution of data to another client. Is confirmed by the streaming server.

As a result of executing the sixth step, if it is confirmed that the client does not have the distribution function, in the seventh step, the streaming server performs, for example, by downloading a distribution function program, Install the distribution function on the client.

As a result, a client that receives data directly from the streaming server or indirectly via another client (that is, a data delivery destination) always has a delivery function. Therefore, the client to which the data is to be distributed can reliably distribute the data as a distribution source when receiving an instruction from the streaming server or a request from another client.

[4] Also, in the above data distribution method, the distribution destination management template holds the network information of the distribution destination of the data, and the streaming server stores the network information of the distribution destination of the data in the data distribution destination. Based on this, a distribution destination of the data to be distributed to the client may be selected from a plurality of distribution destinations of the data.

That is, the distribution destination management table holds network information (for example, IP address) of the distribution destination of the data, so that the streaming server can distribute the network information of the data and the network information of the client. And using the network information of the distribution destination of the data as a criterion when selecting a distribution destination of the data to be distributed to the client from among a plurality of distribution destinations of the data. I can do it.

As a result, the distribution destination of the data belonging to the same or closest network segment as the client that has requested the distribution can be selected as the distribution source. It becomes possible to perform efficient streaming distribution.

[5] In addition, the above data distribution method may be configured so that the streaming server can directly distribute the data even if at least one distribution destination of the data is registered in the distribution destination management table. If the condition is satisfied, the streaming server may further include an eighth step of directly delivering the data to the client.

That is, by setting in advance a predetermined condition under which the streaming server can directly deliver the data, if the predetermined condition is satisfied, the distribution destination of the data is as described above. Even if at least one is registered, the streaming server directly distributes the data in the eighth step.

Thereby, even if the data distribution destination is registered in the distribution destination management table, the data is not transmitted from the data distribution destination but from the streaming server according to the concentration of distribution processing to the streaming server. Can be distributed directly.

[6] Further, in the above data distribution method, the data may be stored in a storage device of the streaming server, and the client stores a copy of the distributed data in its own memory. You may also have a ninth step to save.

That is, if the data is stored in the storage device of the streaming server, for example, as video content in a VOD (Video On Demand) server, in a ninth step, a copy of the distributed data is stored in the storage device. The client saves it in its own memory.

Accordingly, when the client distributes the data to another client as a distribution destination of the data selected later, the client distributes the copy of the data stored in the memory by streaming.

[7] In this case, the client sends a completion notification to the streaming server when the storage of the data in the memory is completed, and the streaming server sends the completion notification to the streaming server. An eleventh step of registering only the performed client as a distribution destination of the data in the distribution destination management table.

That is, when the storage of the data in the memory is completed in the tenth step The streaming server registers only the client that has sent the completion notification to the streaming server in the distribution destination management table as the distribution destination of the data in the eleventh step.

As a result, although the data is not completely stored in the memory, the client is registered in the distribution destination management table as a distribution destination of the data, and distribution to another client is started. Can be avoided.

[8] Further, when the distribution destination of the data registered in the distribution destination management table deletes the data from the memory, a twelfth step of performing a deletion notification to the streaming server, The streaming ′ server may further include a thirteenth step of deleting, from the distribution destination management table, a distribution destination of the data that has performed the deletion notification.

In other words, when deleting the data from the memory, the distribution destination of the data registered in the distribution destination management table sends a deletion notification to the streaming server in the twelfth step. In step, it is deleted from the distribution destination management table by the streaming server.

As a result, the distribution destination of the data that cannot be streamed as a distribution source because the data has been deleted from the memory is deleted from the distribution destination management table. In a pull, it is possible to register only a distribution destination that can stream the data as a distribution source.

[9] In the data distribution method, the data may be real-time stream data, and the distribution source may stream the data to the client by relaying the data.

That is, when the data is real-time stream data such as a real-time video taken by a television camera, the distribution source relays the data to perform streaming distribution to the client.

[10] In this case, the distribution source may not be able to interrupt the streaming distribution by relaying the data.

That is, regardless of whether the distribution source itself needs the data, Originally, streaming distribution by relaying the data cannot be interrupted. In this way, it is possible to prevent the real-time stream from being interrupted due to the distribution destination of the intermediate data (that is, the distribution source to another distribution destination).

[11] In addition, a data distribution system according to the present invention for implementing the above data distribution method includes a client connected to a network, and a distribution destination for registering a distribution destination of data to be streamed and distributed via the network. When a request for streaming distribution of the data is received from the management table and at least one distribution destination of the data is registered in the distribution destination management table, one of the distribution destinations of the data is And a streaming server having a distribution processing unit for instructing the client to perform streaming distribution of the data, wherein the client operates as another one of the distribution destinations of the data. When the distribution processing unit instructs to stream the data to the distribution source, Is characterized by streaming the data to the client connexion said another.

That is, the data distribution system according to the present invention comprises a client connected to a network and a streaming server for streaming data distribution via the network, and the streaming server distributes the data. It has a distribution destination management table for registering destinations and a distribution processing unit.

When receiving a request for streaming distribution of the data from the client, the distribution processing unit, when at least one distribution destination of the data is registered in the distribution destination management table, reduces the distribution amount of the data. Since the data has already been distributed to one distribution destination, one of the distribution destinations of the data is instructed to stream the data to the client.

Also, when another client requests the streaming server to perform streaming distribution of the data, the distribution processing unit sends the data to another client as one of the distribution destinations of the data. May be instructed to be streamed. In this case, the client follows the instruction and streams the data to the another client as the distribution source.

This allows the streaming server to already stream to one of the clients. In the case of data that is distributed by streaming, in response to a distribution request from another client, the streaming server itself distributes the data directly, without transmitting the data registered in the distribution destination management table. One of the distribution destinations becomes the distribution source, and the data can be distributed to the client, so that the concentration of the distribution processing to the streaming server can be eased.

[12] Also, in the above data distribution system, the distribution processing unit instructs the client to request distribution of the data to any one of the distribution destinations of the data. When receiving an instruction from the distribution processing unit, the distribution unit may request one of the distribution destinations of the data to distribute the data.

That is, instead of instructing any one of the data delivery destinations to deliver the data to the client, the delivery processing unit sends the data to any one of the data delivery destinations to the client. One is instructed to request distribution of the data. In this case, the client that has received the instruction from the distribution processing unit requests one of the distribution destinations of the data to perform streaming distribution of the data, and thereby, the client receives one of the distribution destinations of the data. Receives streaming distribution of the data. This may cause the client to be requested by another client to stream the data as one of the destinations of the data

. In this case, the client becomes a distribution source and distributes the data to the another client by streaming.

[13] Further, in the data distribution system, the distribution processing unit checks whether or not the client has a distribution function of distributing the data to another client. If the client does not have the distribution function, the distribution function program may be installed on the client.

That is, the distribution processing unit confirms whether or not the client has a distribution function necessary for streaming distribution of data to another client, and the client has the distribution function. If it is confirmed that the distribution function is not installed, the distribution function is installed on the client, for example, by downloading a distribution function program.

This allows direct access from the streaming server or via other clients Clients that receive data indirectly (that is, data distribution destinations) always have a distribution function. Therefore, the client to which the data is distributed can reliably distribute the data as a distribution source when receiving an instruction from the streaming server or a request from another client.

[14] In the above data distribution system, the distribution destination management table holds network information of a distribution destination of the data, and the distribution processing unit performs a plurality of distribution based on the network information of the distribution destination of the data. The distribution destination of the data to be distributed to the client may be selected from the distribution destinations of the data.

That is, the delivery destination management table holds the network information (for example, IP address) of the delivery destination of the data, so that the delivery processing unit stores the network information of the delivery destination of the data and the network information of the client. It is possible to make a comparison, and use the network information of the distribution destination of the data as a criterion when selecting the distribution destination of the data to be distributed to the client from among the distribution destinations of the data. Can be done.

As a result, the distribution destination of the data belonging to the same or closest network segment as the client that has requested the distribution can be selected as the distribution source, and more efficient streaming distribution can be performed.

[15] In addition, the data distribution system described above is capable of directly distributing the data even if at least one distribution destination of the data is registered in the distribution destination management template. If the condition is satisfied, the distribution processing unit may directly distribute the data to the client.

That is, by setting in advance a predetermined condition under which the streaming server can directly deliver the data, if the predetermined condition is satisfied, the distribution destination of the data is as described above. Even if at least one is registered, the distribution processing unit distributes the data directly to the client.

[16] Further, in the above data distribution system, the data is transmitted in the streaming format. The client may store the distributed copy of the data in a memory of the client device.

In other words, when the data is stored in the storage device of the streaming server, for example, as video content in a V0D (Video On Demand) server, the client copies the distributed data to its own device. Save to memory. Accordingly, when the client distributes the data to another client as a distribution destination of the data selected later, the client distributes the copy of the data stored in the memory by streaming.

[17] In this case, when the client finishes saving the data in the memory, the client notifies the streaming server of the completion, and the streaming server only sends the completion notification to the client. May be registered in the distribution destination management table as a distribution destination of the data.

In other words, only when the data has been stored in the memory, the streaming server is notified of the completion by the streaming server. Register on the table.

[18] Further, when the distribution destination of the data registered in the distribution destination management table deletes the data from the memory, the distribution destination sends a deletion notification to the streaming server, and the streaming server The distribution destination of the data for which the deletion notification has been made may be deleted from the distribution destination management table.

In other words, the distribution destination of the data registered in the distribution destination management table, when deleting the data from the memory, notifies the streaming server of the deletion, whereby the distribution server Deleted from the destination management table.

As a result, the distribution destination of the data that cannot be streamed as a distribution source because the data has been deleted from the memory is deleted from the distribution destination management table. Has a Only distribution destinations that can stream data can be registered.

[19] Further, in the data distribution system, the data may be real-time stream data, and the distribution source may perform streaming distribution to the client by relaying the data. Good.

That is, if the data is real-time stream data such as a real-time video taken by a television camera, the distribution source performs streaming distribution to the client by relaying the data.

[20] In this case, the distribution source may not be able to interrupt streaming distribution by relaying the data.

That is, regardless of whether the distribution source itself needs the data, the distribution source cannot interrupt the streaming distribution by relaying the data. As a result, it is possible to prevent the real-time space 1 and the ream from being interrupted due to the distribution destination of the intermediate data (that is, the distribution source to another distribution destination). BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing an embodiment (1) of a data distribution method and a data distribution system according to the present invention.

FIG. 2 is a sequence diagram showing a content distribution processing procedure in the embodiment (1).

FIG. 3 is a block diagram showing an embodiment (2) of the data distribution method and data distribution system according to the present invention.

FIG. 4 is a flowchart showing an example of the content distribution processing of the server 100 in the embodiment (2).

FIG. 5 is a sequence diagram showing an operation procedure example of registration and deletion of a distribution destination in the distribution destination management table 20 in the data distribution method and the data distribution system according to the present invention. Explanation of reference numerals 100 VOD server

200 networks

10 Video content

20 Delivery destination management table

30_A, 30-1 P, 30-1 S Delivery processing unit

40-1 A, 40-1 P Content storage area

A, P, PP client

In the drawings, the same reference numerals indicate the same or corresponding parts. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an example in which the data distribution method and the data distribution system according to the present invention are applied to a video-on-demand (V0D) system will be described.

Example (1)

FIG. 1 shows an example of a V0D system to which a data distribution method and a data distribution system according to the present invention are applied, wherein clients A and P are connected via a network 200 to a V0D server 100 that performs streaming distribution of video contents 10. Have been.

If the V0D server 100 manages the content of the video content 10 specifically, for example, the content C4, a distribution destination management table 20 that manages the distribution destination of the streaming distribution of each of the contents C1 to C4 is provided. Have. The destination management table 20 shown in the figure is an example at the time when the contents C1, C2, and C4 are distributed to clients P, B, and C, respectively (clients B and C are not shown). It is shown.

Further, the distribution processing unit 30_S that performs the distribution process reads out each of the contents C1 to C4 from the video content 10, and performs streaming distribution to the requesting client as needed.

Clients A and P have content storage areas 40_A and 40-P, respectively, and further have distribution processing units 30-A and 30-P.

In the content storage areas 40—A and 40_P of the clients A and P, copies of the content distributed by streaming from the VOD server 100 are stored, respectively. When it is necessary to perform streaming distribution as a distribution source to another client (not shown), the distribution processing units 30_A and 30-P respectively transmit content from the content storage areas 40_A and 40-P. Read the relevant content and perform streaming distribution.

Although not shown in the figure, a plurality of clients similar to these are connected to the network 200 in addition to the clients A and P, and the same as the clients A and P described below. The contents C1 to C4 can be received from the V0D server 100 in a simple procedure.

FIG. 2 shows a procedure in which the content C1 is distributed from the V0D server 100 to the clients P and A in the configuration of FIG.

Hereinafter, a procedure in which the client P first receives the streaming distribution of the content C1 from the V0D server 100, and further, the client A receives the streaming distribution of the content C1 from the client P will be described with reference to FIGS.

(1) First, client P requests content C1 from V0D server 100 (message Ml). On the other hand, the V0D server 100 checks whether or not the client P has a distribution function (M2 in the same manner). Client P notifies V0D server 100 that it has no distribution function (M3). Therefore, the V0D server 100 performs a distribution function installation process on the client P (step S100_P).

(2) Next, in the V0D server 100, a client specifying process (S200_P in the same manner) is performed in order to confirm whether or not there is a distribution destination that has already distributed the content C1. here

Since the distribution destination that distributed the content C1 is not yet registered in the distribution destination management table 20, the V0D server 100 directly streams the content C1 to the client P (S300_P;). At this time, the client P stores a copy of the distributed content + C1 in the content storage area 40-P.

(3) Next, the client A requests the content C1 from the V0D server 100 (message M4). On the other hand, the V0D server 100 confirms whether or not the client A has the distribution function as in the case of the client P in the above (1) (M5). Here, it is assumed that client A has a distribution function, and client A notifies V0D server 100 that it has a distribution function (M6). Young cry If the client A does not have the distribution function, the fact is notified to the V0D server 100, and the same distribution processing installation processing as in the case of the client P described above is performed (not shown).

In the example of FIG. 2, since the client A already has the distribution function, the V0D server 100 that has received the message M6 performs the client identification processing without performing the distribution processing installation processing (step S200_A).

In this case, the content C1 has already been delivered to the client P in (1) above. Therefore, the client P is registered in the distribution destination management table 20 in the V0D server 100 in association with the content C1 (see the distribution destination management table 20 in FIG. 1). In this case, the V0D server 100 specifies the client P and instructs the client P to deliver the content C1 to the client A (message M7). The client P receiving the message M7 becomes a distribution source, and distributes a copy of the content C1 stored in the content storage area 40-P from the distribution processing unit 30-P to the client A by streaming (S300-A in the same manner). At this time, the client A stores a copy of the distributed content C1 in the content storage area 40-A.

(4) As described in (3) above, after performing the client identification processing (S200—A), the V0D server 100 sends the message M7 to the client A instead of sending the message M7 to the client P. It may be instructed to make a request (message M8). In this case, client A receiving message M8 requests content P1 from client P (message M9).

The client P, which has received the message M9, becomes the distribution source in the same manner as in the case of ③ above, and transmits a copy of the content C1 stored in the content storage area 40—P to the client A from the distribution processing unit 30—P. Streaming (S300_A)

The above is the basic configuration example and operation example of the data distribution method and the data distribution system according to the present invention.

Example (2)

Next, with reference to FIGS. 3 and 4, a description will be given of a process in the case where the content requested to be distributed has already been distributed to a plurality of distribution destinations.

Figure 3 shows the V0D server 100 and clients A and P shown in An ant PP is shown connected to the network 200.

Further, in the distribution destination management table 20 managed by the V0D server 100 in FIG. 3, as shown, the IP address of the client is held as network information of each distribution destination.

Note that, in the distribution destination management table 20 in the figure, the client C (IP address: 192.168.2.2.30) registered as the distribution destination of the content C2 and the client D registered as the distribution destination of the content C3 (IP address: 192.168. 2.40) and E (IP address: 192.168. 1.50) are not shown, but from each IP address, clients C and D are sent to client PP (IP Address: 192.168. 2.10), and the client in the same network segment as client E, client E is client A (IP address: 192.168.1.10) and client P (IP address: 192.168) It can be seen that the client is in the same network segment as 1. 1. 20).

In FIG. 3, the video content 10 and the distribution processing unit 30_S in the V0D server 100, the respective content storage areas 40-A and 40-P in the clients A and P, and the distribution processing units 30_A and 30-P are omitted. Have been.

In this case, in the distribution destination management table 20 of the V0D server 100, the clients PP and P are registered as the distribution destinations of the content C1, and the client C is registered as the distribution destination of the content C2. Clients D and E are registered as distribution destinations of content C3.

In this case, it is assumed that client A requests distribution of content C1 to V0D server 100.

The basic processing flow is the same as that described with reference to FIG. 2, but the details of the client 1, the specific processing (step S200—A) in ③ of the figure are shown in more detail. This is shown in FIG.

The V0D server 100, which has received the distribution request for the content C1 from the client A, first searches the distribution destination management table 20 for the distribution destination of the content C1 in step S1. In step S2, it is confirmed whether or not there is a client registered as the distribution destination of the content C1 in the distribution destination management table 20.

If there is no registered client in step S2, After registering the client A as the distribution destination of the content C1 in the distribution destination management table 20, the content C1 is distributed to the client A in step S4.

In the example of the distribution destination management table 20 shown in FIG. 3, since the clients PP and P have already been registered as distribution destinations of the content C1, the process proceeds to step S5 after step S2, and the registration of a plurality of clients is performed. Check if there is.

When only one client (for example, only client P) is registered as the distribution destination of the content C1, in step S6, for example, the client P is specified, but in the example of the distribution destination management table 20 shown in FIG. Since the clients PP and P have already been registered as the distribution destinations of the content C1, the client P closest to the client A is specified in step S7.

Thereafter, in step S8, the V0D server 100 instructs the specified client P to deliver the content C1 to the client A. In step S9, the V0D server 100 stores the content of the content C1 in the delivery destination management table 20. Register as.

In step S8, the V0D server 100 may instruct the client A to request the specified client P to request the distribution of the content C1.

The method of identifying the client P closest to the client A in the above step S7 is as follows.

A client requesting content distribution (client A in Fig. 4) and a plurality of distribution destination clients registered as distribution destinations of the content requested by the client (client PP and For P), the logical product of each IP address and the mask condition [FFFFFF00 (255.255.255.0)] was obtained, and the IP address and the mask condition of the client requesting the content distribution were obtained Identify the destination client of the IP address that is the logical product that matches the logical product.

If the corresponding destination client is not found by the above mask condition [FFFFFF00 (255. 255. 255. 0)], the mask condition is sequentially set to [FFFF0000 (255. 255. 2 55. 0. 0. 0)] and [FFFFFF00 (255. 255. 255. 0)], and find the one that matches. Even if the mask condition is [FFFFFF00 (255. 255. 255. 0)], the client cannot be specified. Otherwise, the client registered at the top as the distribution destination of the content corresponding to the distribution destination management table 20 is specified.

In the case of Fig. 3, the IP addresses of the client PP and P registered as the distribution destination of the client A and the content C1 are [192.168. 1.10], [192.168. 2.10], And [192. 168. 1.20], the mask condition [FFFFFFOO (255. 255. 255.

0)] and client A and client P match. That is, clients A and P belong to the same network segment.

If the client is specified by the above-mentioned method, streaming distribution from the distribution destination client of the same or closest network segment becomes possible.

In the client specifying process shown in FIG. 4, a flow is shown in which the client A is registered in the distribution destination management table 20 before the content C1 is distributed to the client A.

In this case, before the distribution of the content C1 to the client A is completed, the client A may be instructed by the V0D server 100 to become a distribution source and distribute to another client.

In order to avoid such a situation, the distribution destination may be registered in the distribution destination management table 20 after the distribution of the content is completed as shown in FIG.

In this case, the processing flow corresponding to the processing in Figs.

In the client identification process (step S200_P), the V0D server 100 confirms that the distribution destination has not been registered in the distribution destination management table 20 as in the case of FIG. 2②, and then distributes the content C1 directly to the client P. (S300-1P).

When the client P has finished storing the copy of the content C1 in the content storage area 40_P, the client P notifies the delivery completion of the content C1 (message M10), and the V0D server 100 receives the message M10 for the first time after receiving the message M10. P is registered in the distribution destination management table 20 as the distribution destination of the content C1.

Thereafter, when client A requests content C1 (message Ml

1), the V0D server 100 has already registered the client P in the distribution destination management table 20 as the distribution destination of the content C1 in the client identification processing (step S200—A), as in the case of ③ in FIG. Is delivered to client A to client P. Send a message (message M12).

The client P that has received the message M12 performs distribution processing of the content C1 (S300—A).

When the client A finishes storing the copy of the content C1 in the content storage area 40_A, the client A notifies the delivery completion of the content C1 (message M13), and the V0D server 100 receives the message M13 for the first time after receiving the message M13. A is registered in the distribution destination management table 20 as the distribution destination of the content C1.

After registering the clients P and A in the distribution destination management table 20 as described in ① above, the clients P and A delete the copy of the content C1 from the content storage areas 40-P and 40_A of the own device, respectively. In this case, the client P sends a content C1 data deletion notification (message M14) to the V0D server 100, and the V0D server 100 deletes the information of the client P from the distribution destination management table 20, as shown in FIG. (S500-1P), and the client P deletes the data of the content C1 from the content storage area 40-P (S600-P).

Similarly, the client A sends a content C1 data deletion notification (message M15) to the V0D server 100, and the V0D server 100 deletes the information of the client A from the distribution destination management table 20 (S500_A) and the client P Deletes data of content C1 from content storage area 40-P (S600-A)

In the description of the above embodiments (1) and (2), the V0D system is used as an example. However, in the case of a live server that distributes live video, for example, in FIG. Can be replaced with a live 'server. In this case, the live server does not hold the video content 10, and distributes, for example, a live video captured by a TV camera or the like directly from the distribution processing unit 30_S.

Further, the clients A and P do not need the content storage areas 40_A and 40-P, and need only relay the data distributed by streaming to another client.

It should be noted that the distribution destination management table 20 may be the same as the distribution server management table 20 shown in FIG. Similarly, for multiple contents C1-C4 The client currently being distributed may be registered as a distribution destination in association with a plurality of corresponding live videos L1 to L4 (not shown).

In addition, the distribution processing units 30_A and 30_P of each of the clients A and P may perform streaming distribution to a plurality of different clients simultaneously.

Further, in the above description, when at least one distribution destination corresponding to the requested content is registered in the distribution destination management table 20, the client is identified and the identified client is addressed to another client. Although streaming distribution is used, for example, the number of clients that can be directly distributed by the V0D server 100 is set as a predetermined threshold, and the number of clients that does not exceed the predetermined threshold, that is, there is a margin in the processing capacity of the V0D server 100 In some cases, the V0D server 100 may directly distribute the content to the client that has made the distribution request.

However, also in this case, the distribution function installation process and registration and deletion to the distribution destination management table 20 are performed in the same manner as in the above-described embodiments (1) and (2). As described above, according to the data distribution method and the data distribution system according to the present invention, a client requests a streaming * server connected via a network to perform streaming distribution of data, and When at least one distribution destination of the data is registered in the distribution destination management table for registering the distribution destination, the streaming server transmits the data to one of the distribution destinations of the data. Is instructed to perform streaming distribution to the client, and any one of the distribution destinations of the data that has received the instruction becomes a distribution source, and the data is streamed to the client. It is possible to reduce the concentration of distribution processing to streaming servers.

Claims

1. The first step in which a client requests a streaming server connected via a network to stream data,

When at least one distribution destination of the data is registered in the distribution destination management table, the streaming server distributes the data to one of the distribution destinations of the data to the client. And a blue bite

A third step of streaming distribution of the data to the client, with one of the distribution destinations of the data serving as a distribution source;

A data distribution method comprising:

2. In Claim 1,

Enclosure

In place of the second step, the streaming server instructs the client to request any one of the distribution destinations of the data to distribute the data; and A fifth step of requesting any one of the data distribution destinations to distribute the data.

3. In Claims 1 or 2,

A sixth step between the first step and the second step, wherein the streaming server checks whether the client has a distribution function of distributing the data to another client; And a seventh step in which the streaming server installs a program of the distribution function on the client when the distribution function is not provided.

4. In any one of claims 1 to 3,

The distribution destination management table holds the network information of the distribution destination of the data, and the streaming server determines, based on the network information of the distribution destination of the data, the client from among the plurality of distribution destinations of the data. A data delivery method for selecting a delivery destination of the data to be delivered.

5. In any one of claims 1 to 4, Even if at least one distribution destination of the data is registered in the distribution destination management table,

The streaming server further includes an eighth step in which the streaming server directly delivers the data to the client when a predetermined condition that allows the streaming server to directly deliver the data is satisfied. Data delivery method to be used.

6. In any one of claims 1 to 5,

A data distribution method, wherein the data is stored in a storage device of the streaming server, and the client further stores a copy of the distributed data in a memory of the client device.

7. In Claim 6,

A tenth step in which the client notifies the streaming server of completion when the storage of the data in the memory is completed; and the streaming 'server performs the completion notification of the client. An eleventh step of registering only the data as a distribution destination of the data in the distribution destination management table.

8. In claims 6 or 7,

When the destination of the data registered in the destination management table deletes the data from the memory, a twelfth step of notifying the streaming server of the deletion, the streaming server A thirteenth step of deleting, from the distribution destination management table, the distribution destination of the data for which the deletion notification has been issued.

9. In any one of claims 1 to 5,

A data distribution method, wherein the data is real-time stream data, and the distribution source performs streaming distribution to the client by relaying the data.

10. In Claim 9,

A data distribution method, wherein the distribution source cannot interrupt streaming distribution by relaying the data.

11. Clients connected to the network,

A distribution for registering a distribution destination of data to be distributed via the network. A destination management table and a request for streaming distribution of the data from the client; if at least one distribution destination of the data is registered in the distribution destination management table, one of the distribution destinations of the data; A streaming server having a distribution processing unit for instructing the client to stream-distribute the data to the client;

When the client is instructed by the distribution processing unit to stream the data to another client as one of the distribution destinations of the data, the client sends the data to the another client as a distribution source. A data distribution system that features streaming distribution of data.

12. In Claim 11,

The distribution processing unit instructs the client to request distribution of the data to any one of the distribution destinations of the data. When the client receives the instruction from the distribution processing unit, A data distribution system that requests distribution of the data to any one of the distribution destinations of the data.

13. In claims 11 or 12,

The distribution processing unit checks whether or not the client has a distribution function of distributing the data to another client. If the distribution processing unit does not have the distribution function, A data distribution system, wherein a program is installed in the client.

14. In any one of claims 11 to 13,

The distribution destination management table holds network information of the distribution destination of the data, and the distribution processing unit transmits the data to the client from among a plurality of distribution destinations of the data based on the network information of the distribution destination of the data. A data distribution system for selecting a distribution destination of the data to be distributed.

15. In any one of claims 11 to 14,

Even if at least one distribution destination of the data is registered in the distribution destination management table, if the predetermined condition for directly distributing the data is satisfied, the distribution processing unit deletes the data. A data distribution system for direct distribution to the client.

16. In any one of claims 11 to 15,

A data distribution system, wherein the data is stored in a storage device of the streaming server, and the client stores a distributed copy of the data in its own memory.

17. In Claim 16,

The client sends a completion notification to the streaming server when the storage of the data in the memory is completed, and the streaming server distributes only the client that sent the completion notification to the streaming server. A data distribution system, wherein the data is first registered in the distribution destination management table.

18. In claims 16 or 17,

When the distribution destination of the data registered in the distribution destination management table deletes the data from the memory, a deletion notification is sent to the streaming server, and the streaming server sends the deletion notification to the streaming server. A data distribution system, wherein the executed data distribution destination is deleted from the distribution destination management table.

19. In any one of claims 11 to 15,

A data distribution system characterized in that the data is real-time and stream data, and the distribution source performs streaming distribution to the client by relaying the data.

20. In claim 19,

A data distribution system, wherein the distribution source cannot interrupt streaming distribution by relaying the data.