JP2003348102A - Server, and program for realizing information distribution method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system capable of continuously reproducing data with less errors without keeping a user waiting. <P>SOLUTION: The system decides a prescribed delay and transmits the same data within the time of delay for a plurality of number of times. A receiver side selects data without errors the data received in duplicate and uses the selected data. Since the delay amount is variable but decided in the system, the receiver side can continuously progress the reproduction. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for reducing errors when distributing multimedia data.

[0002]

2. Description of the Related Art In recent years, the spread of networks represented by the Internet has been considerably widespread. Among them, ADSL (Asymmetric Digital)
Subscriber Line), FTTH (Fi
Broadband networks using “Ber To The Home” have also been expanding, and streaming distribution services for multimedia contents using the networks are also expanding. A service called a hot spot using a wireless LAN has also been started. At present, services are provided mainly on those using the IEEE 802.11b standard.
When multimedia data is distributed by wireless as described above, the following two methods are considered. First, T
CP (Transmission Control P)
rotocol: IETF RFC 793 "Tran
Smith Control Protocol
l ") on HTTP (Hyper Text Tran)
sfer Protocol: IETF RFC 26
16 "Hypertext Transfer Pro
tocol--HTTP / 1.1 "). In this method, multimedia data is considered as a file. First, transfer of multimedia data from the server to the client is started over HTTP / TCP. This is a method in which the user is allowed to reproduce the data after all the data is transferred to the client. It is used in mobile phones and the like. Next, UDP (User
Diagram Protocol: IETF RF
C 768 "User Datagram Proto
col ") on the RTP (Real Time Prot
ocol: IETF RFC 1889 "RTP: A
Transport Protocol for Re
al-Time Applications ”). This uses HTTP and RTP. After obtaining data such as content information and presentation description of multimedia data by HTTP,
The client uses RTP to play multimedia data from the server while receiving the multimedia data from the server. This method is used for multimedia streaming using the Internet. Regarding this prior art, for example, “3r
d Generation Partonership
Project; Technical Specif
icationGroup Service and
System Aspects; Transport
nt end-to-end packet switch
chedstreaming service; RT
It is used in the standard of “P use model”.

[0003]

In the prior art, there was a problem in error processing during distribution of multimedia data for wireless communication. First, a method using HTTP / TCP. First, in the case where reproduction is performed after transferring all data, a large memory capacity is required for the client, and further, reproduction is started immediately after the reception is started. There is a problem that can not be. Also, in HTTP / TCP,
In the case of performing reproduction while receiving data, if an error occurs in a part of data during multimedia data distribution, a CRC (Cyclic R) described in a data packet is used.
There is a method for detecting an error and requesting retransmission of the data by using a code such as an E.C. However, although this method can completely correct data, it cannot determine when a retransmission is sent, and thus has a problem in the continuity of processing of multimedia data. Next, a method using RTP / UDP is used. However, in this case, there is a problem that the error processing of the communication layer is only the error correction code and the error resistance is very low.

[0004]

A certain amount of delay is determined in the system, and the same data is transmitted a plurality of times within that time. The receiving side selects and uses the error-free data in the duplicate received data. A typical invention disclosed in the present application is a server having a network interface, control means for controlling information processing, and information storage means, wherein the control means divides a stream acquired by the interface into a plurality of packet data. A header including a continuous sequence number is added to each data, a delay amount or the number of transfers of one packet data is set, and an adaptation including information of the delay amount or the number of transfers is created and output; The data that is continuous according to the sequence number is read into the information storage means the number of times of delay, the read packet is multiplexed and output to the interface, and the data is read from the next data after the first data read. Server that controls the process of repeating and multiplexing Program for the realization of the benefactor.

[0005]

Embodiment 1 First, a first embodiment of the present invention will be described below.
In the present embodiment, a wireless LAN, ie, IEEE 802.11
A connection method using b will be described. FIG.
1 illustrates an overall configuration of a system to which the present embodiment is applied. Multimedia server (1), router (2), wireless LAN access point (3), client (4)
It is composed of The server (1), the router (2), and the wireless LAN access point (3) are connected by a wired network, and the wireless LAN access point (3) and the client (4) are connected by a wireless network. The server (1) has a function of distributing multimedia data stored or sent from another device at the request of a client. Router (2)
It is a connection between the server (1) and the wireless LAN access point, and has a function of determining a data transmission destination and appropriately transmitting the data. The wireless access point (3) has a function of transmitting data received from the router into the wireless LAN,
The client (4) has an interface with the user and has a function of receiving data via the wireless LAN. FIG. 2 illustrates session control of distribution according to the present embodiment. In this embodiment, a server (1) for delivering multimedia data, a wireless access point (3) for transmitting data received from the server (1) to a wireless LAN, and a client (for receiving distributed multimedia data) 4). First, the client (4) makes a wireless connection with the wireless access point (3). When IEEE802.11b is used for wireless communication, wireless scanning is performed by the client (4). That is, first, a probe frame is output from the client (4), then a probe response frame from the access point (3) is detected, and the connectable access point (3) is recognized. Finally, by returning an ACK signal to the access point (3), wireless synchronization is established, and the wireless scanning operation ends. Next, authentication processing is performed with the access point (3), and data communication is enabled. After the wireless data communication is established, the client (4) requests the server (1) to distribute the content information through the wireless access point (3). In the present embodiment, an HTTP GET command is used to transmit the content information, and a request for the distribution of the content information is made. The server (1) responds to the request of the client (4) by, for example, HTML (Hyper
Content information described in Text Markup Language is distributed to the client (4). The user of the client (4) selects from the content information, and from the client (4) to the server (1),
Request distribution of multimedia data. For example, RT
SP (Real Time Streaming Pr)
otocol: IETF RFC 2326 "Real
Time Streaming Protocol
(RTSP) "). Since the media information is distributed from the server (1), the client (4) executes the SETUP command, the PL
The AY command is used to request the start of distribution of multimedia data. The server (1) distributes multimedia data using, for example, RTP.
Here, in the multimedia data using RTP,
There is data including delay information. Here, multimedia delivery using RTP has been described.
Similarly, when multimedia is not used, the delay information is included in the multimedia data. The data configuration of the present embodiment will be described with reference to FIGS. 3, 4, and 5. FIG. In data distribution using a network, data is divided into a plurality of units called packets and distributed. In addition, the data is divided into a plurality of communication layers, and necessary information is added as a header to each communication layer for transmission. In the present embodiment, as shown in FIG. 3, the present invention (5) is applied on the RTP layer. The data configuration on the server side will be described with reference to FIG. Stream (10) in FIG.
Is multimedia data output from the encoder in the server. Data (11) is a data string processed by the RTP layer. In the present embodiment, the stream (1
0) to output data (11). First, the stream (10) is subdivided. The size of the subdivided data may be determined by the size, or may be based on the attribute information of the stream, for example, in the case of a moving image in units of frames. Subsequently, a header (13) is added to the segmented data (12). The subdivided data to which the header has been added are arranged a plurality of times while being rearranged (18). In this embodiment, the fourth data, the fifth data, the sixth data, and the three data are successively arranged, and subsequently, the fifth data, the sixth data,
The seventh data is arranged, and the same data is arranged three times in total. The arranged data is grouped for each of a plurality of data (three data in the present embodiment), added with adaptation data (14), and transferred to a lower layer such as RTP. The configuration of the header and the adaptation data will be described with reference to FIG. As shown in FIG. 5, the information described in the header (13) is sync (20) indicating that the header is the head of the header, and H indicating the size of the header.
-Size (21), D-size (22) indicating the size of data following the header, pid (23) indicating the attribute of data, and seq indicating data as a series of numbers.
(24), rep (25) indicating the branch number of the data. The pid (23) indicates the attribute of the data following the header. Here, 1 is set for multimedia data, and 0 for adaptation data. The branch number is, for example, 0 for data (15) and 1 for data (16) in FIG. The adaptation data has a header (13) at the beginning and has a size (26) indicating the size of the adaptation data, a delay (27) indicating the amount of delay in communication, and a count (28) indicating the number of times the same data of communication is transferred. It is composed. Note that all of the above information is not essential, and information having at least one of delay (27) and count (28) is referred to as adaptation. Embodiment 2 Hereinafter, a second embodiment of the present invention will be described. In this embodiment, a connection method using IEEE 802.11b, which is a wireless LAN, and multicast will be described. FIG. 6 shows the overall configuration of a system to which this embodiment is applied. Multimedia multicast server (30), multicast router (31), wireless LA
N access points (3) and clients (4). Server (30), router (31), wireless L
The AN access point (3) is connected by a wired network, and the wireless LAN access point (3) and the client (4) are connected by a wireless network. The server (30) and the client (4) have a control means for controlling a network interface and information processing, and an information storage means, and the server (30) is a multi-processor which is stored or sent from another device. It has a function of multicast distribution of media data at the request of the client. The router (31) connects between the server (30) and the wireless LAN access point, and has a multicast group management function in addition to a function of determining a data transmission destination and appropriately transmitting the data. The wireless access point (3) has a function of transmitting data received from the router into the wireless LAN, and the client (4)
Has an interface with a user, receives data via a wireless LAN, and realizes an IGMP (Internet Group M) that realizes a multicast function.
analysis Protocol: IETF R
FC 2236 "Internet Group Ma
management Protocol, Version
2)). FIG. 7 illustrates session control of distribution according to the present embodiment. In the present embodiment, a server (3) for distributing multimedia data is used.
0), the data received from the server (30)
N, a wireless access point (3) for transmitting data, and a client (4) for receiving distributed multimedia data. First, the client (4) makes a wireless connection with the wireless access point (3). I to radio
When using EEE802.11b, the client (4) performs wireless scanning. That is, first, a probe frame is output from the client (4), then a probe response frame from the access point (3) is detected, and the connectable access point (3) is recognized. Finally, by returning an ACK signal to the access point (3), wireless synchronization is established, and the wireless scanning operation ends. Next, authentication processing is performed with the access point (3), and data communication is enabled. After the wireless data communication is established, the client (4)
It requests the server (30) to distribute the content information through the wireless access point (3). In this embodiment, the transmission of the content information uses the GE
The distribution of the content information is requested using the T command. In response to a request from the client (4), the server (30) distributes, for example, content information described in HTML to the client (4). The user of the client (4) selects from the content information, and requests the server (30) to deliver multimedia data from the client (4). For example, the IGMP JOIN command is used. The server (30) is a client (4)
To the other client (4),
If the target multimedia data is being distributed, do nothing.
Start distribution if not being distributed. In that case, the server (30) distributes the multimedia data using, for example, RTP. In this case, data including delay information exists in multimedia data transmitted by RTP. Here, multimedia delivery using RTP has been described.
Even when P is not used, similarly, delay information is included in the multimedia data. The data format is the same as in the first embodiment. Embodiment 3 The third embodiment of the present invention describes the operation of the server in the present invention. This embodiment describes the operation of the multimedia server (30) in FIG. The state transition of the server according to the present embodiment will be described with reference to FIGS. FIG. 8 shows the execution state transition of the main thread of the present invention of the server. When the power is turned on, the processing is started, and first, the server is initialized (41). After the initialization is completed, an HTTP thread is created (42), and the HTTP thread is created.
Communication using the P protocol is enabled. After that, it waits for an input from the network (43). H
When TTP GET command is input from network, H
The input instruction is passed to the TTP thread (44). FIG.
FIG. 5 is a diagram showing execution state transition of an HTTP thread of a server. The generated thread performs initialization (50) and waits for an input from the main thread (51). When there is an input, the input command and URL are interpreted (54), and when the content information is requested, the content information is created as data described in HTML (55). The created data is distributed using HTTP (56), and the process returns to waiting for input. In the case of a request for stream data, a stream thread is generated (53), and the process returns to input waiting. FIG. 10 is a diagram showing an execution state transition diagram of the stream distribution thread of the server.
The generated thread performs initialization (60) and distributes stream data (62). From other threads,
When the distribution stop is selected, the distribution is stopped and the thread is deleted (62). FIG. 11 is a flowchart illustrating the detailed operation of the server when distributing multimedia data. First, the entire initialization (71) is performed, and subsequently, the distribution data is initialized (72). next,
The delay amount expressed as “delay” and the number of repetitions expressed as “count” in the adaptation data of FIG. 5 are set (73). In the present invention, the same data is distributed a plurality of times. At this time, the difference between the time at which the same data is distributed first and the time at which the same data is distributed last is the delay amount, and the number of times the same data is distributed. Is the number of repetitions. These data are written to the output buffer as adaptation data (74). Thereafter, the delay counter is initialized (75). The data reading position is determined from the transmission data head position n and the delay counter k. The data is read (76), a header is added to the data (77), and the read data is written to an output buffer (78). The delay counter k is incremented by 1 (7
9) When k is smaller than the delay set amount Td (80),
Returning to data reading, if k is equal to or greater than Td, the transmission data position n is incremented by 1 (81). If all data has been transmitted (82), the process ends here (84). If all data has not been transmitted, it is determined whether to insert adaptation data (83). If the adaptation data is to be inserted, the process branches to the creation of adaptation data. If the adaptation data is not inserted, the process branches to the initialization of the delay counter k. Embodiment 4 A fourth embodiment of the present invention describes another embodiment of the server operation in the present invention. This embodiment describes the operation of the multicast server (30) in FIG. The state transition of the server according to the present embodiment will be described with reference to FIGS. FIG. 12 shows the execution state transition of the main thread of the server. When the power is turned on, the processing is started, and first, the server is initialized (41). After the initialization, an HTTP thread is created (42) and an IGMP thread is created (46), and input from the network is awaited (43). When the HTTP GET command is input from the network, the command input to the HTTP thread is passed (44), and when the HTTP GET command is input from the IGMP JOIN command network, the command input to the IGMP thread is passed (47). FIG. 13 is a diagram showing transition of the execution state of the HTTP thread of the server. The generated thread performs initialization (50) and waits for an input from the main thread (51). When there is an input, the input command and URL are interpreted (5.
4) If the content information is requested, the content information is created as data described in HTML (55). The created data is distributed using HTTP (56), and the process returns to waiting for input. FIG. 14 shows the server I
FIG. 4 is a diagram illustrating a transition diagram of an execution state of a GMP thread. The generated thread performs initialization (60), and waits for an input from the main thread (61). When there is an input, the input command and URL are interpreted (6.
4), confirm whether the request for the corresponding multimedia data is already being delivered (65). If the requested multimedia data is not being delivered, a stream data thread is created (66). If the requested multimedia data is already being delivered, the process returns to the input wait state without doing anything. If distribution stop is selected by another thread, distribution is stopped and the thread is deleted (63). The operation of the server at the time of multimedia data distribution is the same as that of the third embodiment described in FIG. Embodiment 5 The fifth embodiment of the present invention describes the operation of the client in the present invention. This embodiment describes the operation of the wireless LAN client (4) in FIG. The state transition of the client according to the present embodiment will be described with reference to FIGS. FIG. 15 shows the execution state transition of the main thread of the present invention of the client.
When the power is turned on, the processing is started, and first, the client is initialized. After the completion of the initial setting, the network system is started (91), and the user waits for an input (92). When the user selects to receive the multimedia data, the application starts (9).
4) An HTTP thread is created (95), and communication using the HTTP protocol is enabled. Thereafter, input from the user is waited (92). When the content information acquisition is selected by the user, the data acquisition destination URL is passed to the HTTP thread (96). FIG.
FIG. 4 is a diagram showing execution state transition of an HTTP thread of a client. The created thread is initialized (10
0), and waits for input from the main thread (10
1). Command and U entered when there is an input
The RL is interpreted (103), and if content information is requested, an HTTP GET command is generated (10).
4), send to the network by HTTP (105), and return to waiting for input from the network (101). When receiving data in which content information is described in HTML, display data is created and output (106). After the output is completed, the process returns to input waiting. FIG. 17 is a diagram showing transition of the execution state of the stream reception thread of the client.
The created thread performs initialization (110) and waits for acquisition of delay information (111). After the delay information is obtained, stream data is received (112). If the reception stop is selected by another thread, the reception is stopped and the thread is deleted (113). FIG. 18 is a flowchart illustrating the detailed operation of the client when receiving multimedia data. Retrieve the received data (12
2), it is confirmed whether it is adaptation data (123). In the case of the adaptation data, the delay amount and the number of repetitions, which are the delay and the count, of the adaptation data in FIG. 5 are extracted (132). After the extraction, the adaptation data acquisition flag is set (133), and the process returns to the reception data extraction. If the received data is not adaptation data, the adaptation data acquisition flag is checked (124). If the adaptation data confirmation flag has not been set, the process returns to reception data extraction. If the adaptation data confirmation flag is on, the header information is extracted and the data storage position is checked (12).
5). If it is determined from the data storage position information that the data has already been acquired, the data is discarded, and the process returns to data extraction. If not, the process proceeds to the next step (126). Next, the error status of the data is checked (127). If there is no error, the data is written (129), the data acquisition information is updated (130), and the data is passed to the upper layer (131). If there is an error in the data, the amount of delay of the data is checked (134). If the error has not yet been reached, the flow returns to data extraction. If it has reached, the information that failed to acquire the data is passed to the upper layer (13
5). After that, the process returns to data extraction. In this embodiment, both the delay amount and the number of repetitions are taken out when the delay information setting (132) is performed again, but it is not always necessary to take out both information. Embodiment 6 A sixth embodiment of the present invention describes another embodiment of the client operation in the present invention. This embodiment describes the operation of the wireless LAN client (4) in FIG. The state transition of the client according to the present embodiment will be described with reference to FIGS. FIG.
Is the execution state transition of the main thread of the present invention of the client. When the power is turned on, the process starts, and first, the client is initialized (97). After the completion of the initial setting, the network system is started (97), and the user waits for an input (92). When the user selects to receive the multimedia data, the application starts (94) and creates an HTTP thread (9).
5) Then, an IGMP thread is created (98), and the process returns to waiting for an input from the user. When the content information acquisition is selected by the user, the data acquisition destination URL is passed to the HTTP thread (96). When the user selects the acquisition of the content data, the content data U
The RL is passed to the IGMP thread (99). In this embodiment, the execution state transition of the HTTP thread of the client is the same as that of the fifth embodiment described in FIG. FIG.
FIG. 7 is a diagram illustrating execution state transition of an IGMP thread of a client. The generated thread performs initialization (140) and waits for an input from the main thread (141). When there is an input, the input command and URL are interpreted, and if content information is requested,
Generate JOIN command (142), send to network,
A stream receiving thread is generated (143), and the process returns to input waiting. In the present embodiment, the flow chart for explaining the transition of the execution state of the stream receiving thread of the client and the detailed operation at the time of receiving the multimedia data of the client is the same as that of the fifth embodiment shown in FIG. Although the embodiments of the present invention have been described above, the scope of application of the present invention is not necessarily limited to the wireless LAN, and the layer configuration may not necessarily be as described in the embodiments. Further, the flow of operation in the server and the client can also be realized by reading out a program stored in the medium.

[0006]

The present invention relates to a process for reducing errors when distributing multimedia data, and solves the problem of error handling during multimedia data distribution for wireless communication of the prior art. Specifically, a certain amount of delay is determined in the system, and the same data is transmitted a plurality of times within that time. The receiving side selects and uses the error-free data in the duplicate received data. As a result, the receiving side can provide a system capable of continuous reproduction without causing the user to wait with a low error. Further, although the delay amount is variable, since it is determined in the system, the receiving side can continuously perform reproduction within the delay amount.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a connection.

FIG. 2 is an overall session control diagram.

FIG. 3 is a diagram showing a protocol structure.

FIG. 4 is a data reconstruction diagram.

FIG. 5 is a diagram showing header information.

FIG. 6 is a schematic diagram of a connection when multicast is used.

FIG. 7 is an overall session control diagram when multicast is used.

FIG. 8 is a state transition diagram of a main thread of the server.

FIG. 9 is a state transition diagram of an HTTP thread of the server.

FIG. 10 is a state transition diagram of a stream distribution thread of the server.

FIG. 11 is a diagram illustrating an algorithm of a server.

FIG. 12 is a state transition diagram of a main thread of a server when multicast is used.

FIG. 13: HT of server when using multicast
The state transition diagram of a TP thread.

FIG. 14: Server IG when using multicast
FIG. 4 is a state transition diagram of an MP thread.

FIG. 15 is a state transition diagram of a main thread of a client.

FIG. 16 is a state transition diagram of an HTTP thread of a client.

FIG. 17 is a state transition diagram of a stream distribution thread of a client.

FIG. 18 is a diagram showing an algorithm of a client.

FIG. 19 is a state transition diagram of a main thread of a client when using multicast.

FIG. 20 is a state transition diagram of an IGMP thread of a client when multicast is used.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Multimedia server 2 ... Router 3 ... Wireless LAN access point 4 ... Client 5 ... Data processing layer 10 of this invention ... Stream 11 ... Output data 12 ... Segmented data 13 ... Header 14 ... Adaptation data 15 ... Data 16 ... Data 17 ... Data 18 ... Fragmented data 20 ... Code 21 indicating the head of the header 21 ... Code 22 indicating the size of the header 23 ... Code 23 indicating the size of the data following the header 23 .Code 24 indicating the attribute of the data Reference numeral 25 denotes a data branch number 26 Reference numeral 26 denotes an adaptation data size Reference numeral 27 denotes a communication delay amount Reference numeral 30 denotes the number of times the same data is transferred 30 Multimedia multicast server 31 ... Multicast router 41 ... Initial setting of server main thread 2. Creation of an HTTP thread by the server main thread 43 ... Waiting for input of the server main thread 44 ... Communication of the server main thread to the HTTP thread 46 ... Creation of an IGMP thread by the server main thread 47 ... Creation of the server main thread Communication to IGMP thread 50 Initialization of HTTP thread of server 51 Waiting for input in HTTP thread of server 52 Request to delete HTTP thread of HTTP thread of server 53 Creation of stream thread in HTTP thread of server 54 URL interpretation in HTTP thread 55 HTTP data creation in server HTTP thread 56 HTTP data transfer in server HTTP thread 60 Initialization in server stream delivery thread 61 Server stream Stream delivery in delivery thread 62 ... Stream delivery thread deletion request in server stream delivery thread 63 ... Initialization in server IGMP thread 64 ... Input waiting in server IGMP thread 65 ... URL interpretation in server IGMP thread 66: Stream status confirmation by IGMP thread of server 69: Stream thread creation by IGMP thread of server 71: Initialization 72: Initialization of distribution data 73: Setting of delay amount and number of repetitions 74: Writing of adaptation data 75 ... Initialization of delay amount counter 76 ... Reading of data 77 ... Adding header to data 78 ... Writing of data to output buffer 79 ... Increment of delay amount counter 80 ... Confirmation of delay amount setting 81 ... Increment of transmission data position 82 ... Data amount check Check 83: Addition of adaptation data 91: Start of network 92: Waiting for input of client main thread 94: Start of application of client main thread 95: Creation of HTTP thread of client main thread 96: With client main thread Communication with the HTTP thread 100: initialization of the client HTTP thread 101: waiting for input by the client HTTP thread 103: interpretation of commands and URLs by the client HTTP thread 104: generation of GET instructions by the client HTTP thread 105: HTTP in the HTTP thread of the client
Transfer 106 Display on client HTTP thread 110 Initialization on client stream thread 111 Waiting for delay information on client stream thread 112 Reception of stream data on client stream thread 113 Deletion of client stream thread Reference numeral 121: Initialization upon reception of data by the client 122: Extraction of reception data upon reception of data by the client 123: Adaptation check upon reception of data by the client 124: Adaptation flag check upon reception of data by the client 125: Upon reception of data by the client Data storage position check 126 ... Acquired data check at client data reception 127 ... Error check at client data reception 128 ... Error confirmation in data reception of client 129 Data writing in client data reception 130 Data information update in client data reception 131 Interface with upper layer 132 in client data reception 132 Client data reception Delay information setting 133: Adaptation acquisition flag set at client data reception 134: Data delay amount check at client data reception 135: Error information transmission to upper layer at client data reception 140: Client IGMP thread Initialization 141: Waiting for input in the client IGMP thread 142: JOIN in the client IGMP thread
Instruction generation 143: Generation of a reception thread in the IGMP thread of the client.

Claims (7)

[Claims] 1. A server having a network interface, control means for controlling information processing, and information storage means, wherein said control means divides a stream acquired by said interface into a plurality of packet data, A header including a continuous sequence number is added to the data, and at least one of the delay amount and the number of transfers of the one packet data is set to create an adaptation including the information of the delay amount or the number of transfers. And reads the continuous data in accordance with the sequence number into the information storage means, multiplexes the read packet and outputs the multiplexed packet to the interface. Repeat the process of reading and multiplexing the above data from the data of Server and controlling the processing performed. 2. The server according to claim 1, wherein the control unit further controls a process of adding the adaptation at the time of outputting the multiplexed packet. 3. A program for causing a server connected to a network to implement an information distribution method, wherein the server has a network interface, control means for controlling information processing, and information storage means, The storage means stores a plurality of packets, each of which is a packet obtained by subdividing one stream and having a header including a continuous sequence number according to the stream configuration, wherein the information distribution method sets a delay amount and sets the delay amount information. Creating an adaptation including and outputting the same to the interface; anda reading step of reading the data continuous according to the sequence number the number of times of the delay amount;
Multiplexing the read packet and outputting the multiplexed packet to the interface; and repeating the data read and output steps from the next data after the first read data. A program. 4. The method according to claim 3, wherein the adaptation is created by setting the number of transfers of one packet data in place of the delay amount, and the step of reading the data is performed according to the number of transfers. Program. 5. The program according to claim 3, wherein the information distribution method further includes a step of subdividing one stream into a plurality of packets and attaching a header including a sequence number to each packet. 6. An information terminal having a network interface, control means for controlling information processing, and information recording means is provided with delay amount information or one-time information via the interface.
Obtaining an adaptation including the number of times of transfer of the packet data, obtaining multiplexed data via the interface, and storing header information of each data multiplexed with the data and the storage means. A step of determining whether or not the data has been acquired from the data acquisition history; and confirming that there is no error with respect to the packet data determined to have not been acquired, and a step of reading.
Writing the acquisition of the packet data in the data acquisition history, and confirming the arrival state from the data acquisition history and the information on the delay amount or the number of transfers, and outputting the acquired data to the interface. A program characterized by being executed. 7. In the above-mentioned processing, when it is determined that there is an error in the data content in the error confirmation step, the possibility of re-acquisition of the data is determined by referring to the information of the delay amount or the number of transfers. The program according to claim 6, further comprising: a step; and outputting error information to the interface when the determination is not possible, and returning to the data acquisition step when the determination is possible. .