JP2002232478A - Transmitter, receiver and broadcast data distribution method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmitter that realizes re-transmission of data with a higher efficiency based on a result of reception by a receiver and to provide the receiver and a broadcast data distribution method. SOLUTION: A re-transmission reception means receives a re-transmission request from the receiver and a re-transmission request storage means stores a re-transmission request. Succeedingly, a re-transmission control means selects a transmission channel used for re-transmission of data based on the re- transmission request from a multiple access distribution channel or a 2-way communication channel and retransmits the data through the selected transmission channel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitting apparatus, a receiving apparatus, and a broadcast data distribution method. The present invention relates to a transmitting device, a receiving device, and a broadcast data distribution method for receiving the broadcast data on the side.

[0002]

2. Description of the Related Art In recent years, services for distributing digital contents such as music data (song data), moving images, still images, and text data via the Internet have been actively performed. In this case, bidirectional communication such as a telephone line is used for transmitting the content.

On the other hand, broadcasting is also used as a means for distributing data. Since the broadcast can transmit (broadcast) the same data to many users at the same time while performing one-way communication, the broadcast is used for services with many users. Conventionally, the above-mentioned broadcasting was limited to analog broadcasting, but in recent years, digital broadcasting services using satellites and cable television (CATV) as media have become widespread, and digital terrestrial broadcasting services have been implemented. .

[0004] In the above-mentioned digital broadcasting, the transmission method is more suitable for distribution of digital data, that is, the above-mentioned contents. Since a wide band can be used, the content distribution service is already provided for a part of digital broadcasting using a satellite. In this case, since the content is distributed from the satellite to the fixed receiving device, the receiving device can receive to some extent stable while performing one-way communication. However, even though it is a fixed receiving device, it is not always possible to completely receive the distributed content. Therefore, the carousel method is used as a technique for distributing contents by one-way communication.

[0005] The carousel system is a system for repeatedly delivering target data in a data broadcast included in a digital broadcasting service.
rnational Organization For Standardization / Intern
ational Electrotechnical Commission) 13818-
6 is defined. That is, even if the data received in the first data broadcast is incomplete, such as partial omissions, the receiving device combines the data received with the second, third,. The above incomplete data can be complemented. With the above technology, the reliability of content distribution in one-way communication is improved.

Recently, portable telephones and personal digital assistants (PDAs: Personal Digital (Data) Assistants),
2. Description of the Related Art Mobile terminals such as in-vehicle radios are used everywhere, and the mobile terminals are being made multifunctional.
As one of such multi-functions, there is a provision of a reception function of the broadcast service. This is to download music data or the like via a digital broadcasting service at the mobile terminal and store and reproduce the music data.

[0007] Here, when trying to apply the content distribution service by broadcasting to the mobile terminal, it is difficult to ensure the reliability of content distribution only by using the carousel method. This is because, unlike a fixed receiving device, the receiving condition of the broadcast service is significantly changed in the mobile terminal. Here, it is possible to increase the certainty of content distribution to some extent by increasing the number of repetitions of data distribution in the carousel method. However, since the increase in the number of repetitions substantially reduces the amount of data distribution per unit time, it cannot be said to be an essential solution.

Therefore, as a method for improving the certainty of the content distribution, Japanese Patent Application Laid-Open No. 2000-13440 discloses
A technology using a bidirectional communication path in addition to the one-way communication has been disclosed. That is, using the (two-way) communication function using, for example, a telephone line, provided in the receiving device,
Only data that has failed to be received (missing data, etc.) is received using the bidirectional communication function. As a result, it is possible to provide a digital content distribution service or the like that solves the problem of one-way communication while enjoying the advantages of broadcast distribution using a broadband.

In the technique described in Japanese Patent Application Laid-Open No. H11-17737, the receiving apparatus transmits information related to data (packet) that has failed to be received to a transmitting terminal provided in a broadcasting station or the like, and transmits the information. In the terminal, the data (packet) for which the reception has failed based on the information is distributed again using broadcast (one-way communication).

[0010]

An advantage of the content distribution using the digital broadcasting is that the data distribution unit price based on the broadcast distribution is reduced.

However, if missing data is received using, for example, the two-way communication function of the receiving device as described above, it can be said that the data delivery unit price will eventually increase. That is, the user of the mobile terminal usually bears the line usage fee such as a telephone line used for the two-way communication. For this reason, for example, if a mobile terminal that could not receive most of the predetermined music data tries to receive the missing music data via a telephone line, there is a problem that the line usage fee becomes high.

[0012] In the above-mentioned broadcasting of digital broadcasting, the receiving situation on the receiving device side varies greatly depending on, for example, the weather. In other words, in a bad weather situation, data loss or the like is likely to occur on the receiving device side, and the receiving device in which the data loss has occurred can collectively use the telephone line or the Internet, for example, to lose data (missing packet). A retransmission request is made to receive the For this reason, it is necessary for the broadcasting station to secure the number of lines that can simultaneously process a large amount of retransmission requests, and when using the Internet, it is necessary to secure processing capacity and bandwidth that can be handled by the Internet. However, when the same data is transmitted over a wide area as in the case of digital broadcasting, it can be said that it is impossible to respond to the retransmission request that occurs simultaneously. Further, for a retransmission request from a mobile terminal or the like that cannot receive most of the music data described above, it takes a long time just to transmit the data of the missing part of one mobile terminal. It can be said that it is even more impossible to process such a retransmission request from a mobile terminal.

[0013] In view of the above two points,
It is considered that it is substantially difficult to apply the technology using a two-way communication path described in Japanese Patent Application Publication No. 0-13440 to wide area broadcasting.

Further, in the technique described in Japanese Patent Application Laid-Open No. H11-17737, although it is described that the number of times of retransmission of a packet and the time limit can be set, all of the techniques for responding to the retransmission request are described. Packets are transmitted using broadcasting. That is, when the above technology is applied to a wide area broadcast, for example, even if a retransmission request is made by one receiver, the corresponding packet is distributed via a broadcast shared by all the receivers. Can be said to be wasteful. In addition, by limiting the number of times of retransmission and the time limit, a receiving device that cannot normally receive only some of the packets eventually discards the received incomplete content because it cannot be used. . That is, some receiving devices
The content distribution service cannot be received. It can be said that there is almost no problem if only a small number of terminals cannot receive services, but especially in the case where the number of mobile terminals where missing data can always be generated is expected, content distribution by broadcasting is expected. It can be said that this technique alone is not enough to implement the above. Also,
When the distribution service is charged, it is a problem that the service cannot be received by only some terminals.

The present invention has been made in view of such a problem, and realizes more efficient data retransmission based on a reception result by a receiving device, and uses the above reception result to grasp the reception status and charge. Transmission device that enabled
It is an object to provide a receiving device and a broadcast data distribution method.

[0016]

The present invention employs the following means to achieve the above object. That is, it is assumed that the receiving apparatus receives data broadcasted from the transmitting apparatus via a broadcast path using a broadcast wave as a medium. Here, the error detection unit detects an error in the received data, and the retransmission request control unit transmits a retransmission request, which is a request for retransmission of data containing the error, to a bidirectional communication path capable of bidirectional data transmission. To send through. continue,
The receiving means receives data corresponding to the retransmission request from a broadcast path or the two-way communication path.

In the transmitting device corresponding to the receiving device, the retransmission request receiving means receives the retransmission request from the receiving device, and the retransmission request storing means stores the retransmission request. continue,
The retransmission control means selects a transmission path used for retransmission of data from the broadcast distribution path or the bidirectional communication path based on the retransmission request, and retransmits the data.

As described above, by selecting a transmission path to be used for retransmission by the transmission apparatus based on a retransmission request from the reception apparatus, for example, packets that need to be retransmitted in large quantities are transmitted from the broadcast transmission path. It is possible to perform retransmission, such as transmitting a packet that does not cause any problem with a relatively small amount of retransmission from a bidirectional communication path. As a result, waste that can occur in retransmission using the broadcast distribution path, that is, effective use of the broadcast distribution path by minimizing retransmission using the broadcast distribution path for packets addressed to a small number of receivers is considered. It becomes possible. Further, it is possible to solve the problem of securing a line, the problem of preparing more line capacity and processing capacity than necessary, which may occur in retransmission using a bidirectional communication path, and the like. In addition, the receiving apparatus can reduce the line usage fee as compared with the case where a large amount of missing packets are all obtained by using the two-way communication path, and it is possible to reliably obtain the required content.

When data reception and the retransmission request are performed in units of packets constituting the data,
The data reconfiguring means constituting the receiving apparatus has a configuration in which the data is reconfigured using a packet corresponding to a retransmission request received from a broadcast distribution path or a bidirectional distribution path, and a normally received packet.

Further, there is a configuration in which data selection means constituting the receiving device selects data for which a retransmission request is made based on a predetermined threshold. With this configuration, it is possible to reduce the load on the transmission device, for example, when complementing a missing packet using a bidirectional communication path, by excluding data that takes a long time to supplement the missing packet from the target of the retransmission request in advance. It is. Further, since the time required for complementing the data selected as the complement target is short, it is possible to reduce the financial burden when the user uses the two-way communication path.

Since the data selection means accepts the selection of data to be received by the user, it is not necessary to supplement data not required by the user, so that the load on the transmission device can be further reduced. It becomes possible.

Further, there is also a configuration in which the retransmission request control means specifies a data retransmission route in the retransmission request.

In this configuration, the path at the time of retransmission of the lost packet can be selected by the receiving apparatus. For example, contents which are not important to the user may not be able to be received, but using a broadcast distribution path which is not charged. Reception and important contents can be selected in accordance with the degree of importance, such as being surely received using a two-way communication path even if the contents are charged. In addition, when the user enters an underground shopping mall where the broadcast does not reach, for example, a bidirectional communication path is selected, and a broadcast distribution path is selected if the broadcast can be received. It is possible.

Still further, retransmission control means constituting the transmission device dynamically changes transmission efficiency or transmission quality in the broadcast distribution path based on the number of retransmission requests stored in the retransmission request storage means. There is a configuration.

[0025] With this configuration, the transmission device can always maintain optimal transmission efficiency and transmission quality.

[0026] Further, on the premise of a transmitting device that broadcasts data via a broadcasting channel using a broadcast wave as a medium, the broadcast transmission control means is configured to receive the data that cannot be received by the receiving device to which the data is to be transmitted. The retransmission request receiving means receives the retransmission request, which is a request for retransmission of the unreceivable data, from the receiving device, the retransmission request storage means stores the retransmission request, There is a configuration in which the reception status of the receiving device is counted based on the retransmission request stored in the request storage unit.

In this configuration, by transmitting unreceivable packets at a predetermined timing, it becomes possible to grasp the content reception status (audience rating) from the number of retransmission requests received.

[0028] Also, the broadcast transmission control means constituting the transmitting device transmits unreceivable data to the receiving device to which data is to be transmitted, and the retransmission request receiving means transmits the unreceivable data from the receiving device to the receiving device. Receiving apparatus that receives a retransmission request that is a request for retransmission, retransmission request storage means stores the retransmission request, and charging means transmits the retransmission request based on the retransmission request stored in the retransmission request storage means Authentication and / or accounting.

In this configuration, the transmitting apparatus operates the content to generate a retransmission request from the receiving apparatus, thereby enabling authentication of the receiving apparatus, restriction of a distribution destination, billing of paid data, and the like.

Further, assuming a receiving apparatus for receiving a plurality of contents included in data broadcast-transmitted from a transmitting apparatus via a broadcast distribution path using a broadcast wave as a medium, the error detecting means detects the received data. Detects errors in the packets that make up the packet, and the data selection means eliminates the content including the packet containing the error, creates a distribution data list consisting of only the content that can be received normally, and allows the user to select the distribution data list Is also displayed.

The transmitting device and the receiving device can be embodied using a computer. In this case, the transmitting device,
Each unit constituting the receiving apparatus is embodied by running a program on a computer.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a transmitting apparatus, a receiving apparatus, and a transmitting / receiving system according to the present invention will be described with reference to the drawings. It should be noted that the following embodiments are examples embodying the present invention, and do not limit the technical scope of the present invention. Here, a distribution service of music data by data broadcasting will be described as an example of the content. (Embodiment 1) First, with reference to FIG. 1, an overall configuration of a transmitting apparatus, a receiving apparatus, and a transmitting / receiving system according to the present invention will be described.

A broadcasting station on the transmitting side when distributing music data includes a transmitting device 101. Here, the transmitting apparatus 101 receives music data from, for example, a music server 102 that provides music data for distribution, processes the music data into a predetermined format using a predetermined procedure, and processes the broadcast data. It broadcasts to the receiving device via 121. Here, “broadcasting” refers to a method of transmitting predetermined data to a plurality of receiving devices at once. The broadcast is, for example, digital terrestrial broadcasting, digital satellite broadcasting, cable television (CATV), or the like, and is classified according to the broadcast distribution path 121.

The receiving device 131 serving as a receiving side when the music data is distributed is, for example, a television, a broadcast tuner, an STB (Set-Top Box), a mobile phone, or the like. still,
The STB is a generic name of devices that provide additional functions by connecting to a home television, such as a control box of a cable television or a terminal device of a communication karaoke.

When the receiving device 131 receives the broadcasted music data, the receiving device 131 may, for example, use a television,
The data is transmitted to a reproducing device 132 such as a radio or a stereo, and the reproducing device 132 reproduces the received music data. still,
The transmission / reception system includes the transmission device and the reception device. The above is an outline of distribution of music data, and details will be described later.

[Data Structure] Next, details of the music data transmitted from the transmitting apparatus 101 to the receiving apparatus 131 will be described.

In the first embodiment, the distribution data used for distributing the music data can be roughly classified into two types. That is, the content information 200 shown in FIG. 2 and the content data 300 shown in FIG.

The content information 200 has a table meaning of the music data to be distributed, and includes a content identifier 301, a content name 302, and a content attribute 30.
3 and additional information 320 are included. The additional information 320 includes a data size 304, a number of packets 305,
Transmission method 306, accounting method 307, retransmission request permission 30
8, a retransmission request destination 309, a transmission start time 310, a transmission end time 311, and an error correction code 312.

The content identifier 301 is information capable of uniquely identifying data to be distributed, and the content name 302 includes information indicating the content of the data, that is, a music name (song name), an artist name, and the like. The content attribute 303 stores the type of data (moving image, audio, text, etc.) and the format of data (MPEG, PCM, etc.). Further, the data size 304 indicates the total size of the content data 300 corresponding to the content identifier 301, and the number of packets 305 indicates how many packets the content data 300 is divided into and transmitted. The billing information 307 stores information indicating whether the distributed music data is paid or not, and the retransmission request permission 3
08 indicates whether it is possible to request retransmission when reception has failed. When the retransmission request permission 308 is “requestable”, the retransmission request destination 309 is an address (URL: Uniform Res) to which retransmission should be requested.
Information such as “source locators” and a telephone number are stored. The transmission start time 310 and the transmission end time 311 indicate the time during which the content data 300 is transmitted. That is, since the above-described carousel method is usually used for the content information 200 and the content data 300, the same data is repeatedly transmitted within a fixed time. Therefore, if there is a packet that has not been received at the transmission end time 311, the receiving device 131 can determine the packet that has not been received as a missing packet. The error correction code 312 is a bit string for checking whether there is any abnormality in the content data 300.

The content data 300 is shown in FIG.
The encoded music data 401 shown in (a) is divided into, for example, a plurality of data 410 to 419 shown in FIG. 4B, and a header 336 and an error correction code 335 are added to each of the data 410 to 419. This is an added configuration (FIG. 4C). Note that the encoding is performed, for example, using MPEG.
This is an audio encoding method such as 2-AAC or MPEG1 Audio layer3. Each of the data 410 to 419 corresponds to the data 334 of the content data 300, and the header 336 includes a content identifier 331, a packet identifier 332, and a packet size 333.

The content identifier 331 indicates which content information among the plurality of content information 200 corresponds. The packet identifier 332 is used to determine which packet is requested when a retransmission request is received from the receiving device after the distribution of the content data 300, and is attached, for example, by a serial number. The packet size 333 indicates the data size of the content data 300.

The content data 300 is multiplexed and distributed to each receiving device on a broadcast wave. In the carousel method, as shown in FIG. 4D, the content information 200 and the content data 300 are transmitted. Are repeatedly transmitted by the transmitting apparatus 101 at a constant cycle.

[Data Distribution Processing in Transmitting Apparatus] Next, the distribution processing of content (music data) in the transmitting apparatus 101 will be described.

First, the music data 401 input from the music server 102 or the like is processed into the content data 300 by the packet generation means 103 and the packet data is stored in the packet storage means 10.
9 (FIG. 5: S501). At this time, the content information 200 corresponding to the content data 300 is also generated at the same time.

Here, the content information 200 includes
Content identifier 301 corresponding to each music data 401
Is stored. In addition, the content name 30 described above
2. The content attribute 303 and the additional information 320 are also added. The information to be added may be information added by an operator in advance, or may be automatically added contents (data size, packet number). Etc.), the packet generation means 101 may add the information.

Similarly, a content identifier 331 corresponding to the music data 401 is stored in the content data 300.

The generated content information 200 and content data 300 are temporarily stored in the packet storage unit 1.
09 or directly stored in the broadcast transmission control unit 104.
Sent to.

Subsequently, the broadcast transmission control means 104 transmits the content information 200 to the broadcast transmission means 105, and the broadcast transmission means 105 transmits the received content information 200
Is transmitted to the receiving apparatus 131 via the broadcast distribution channel 121 (FIG. 5: S502).

Next, the broadcast transmission control means 104 similarly transmits the content data 300 to the broadcast transmission means 105, and the broadcast transmission means 105 transmits the received content data 300 to the receiving apparatus via the broadcast distribution path 121. 131
(FIG. 5: S503).

The transmission of the content data 300 by the broadcast transmitting means 105 is performed in accordance with predetermined content information 20.
The process is performed until the content data 300 corresponding to 0 is completely transmitted (FIG. 5: S504 No → S503 → S504Y).
es).

As described above, for example, music data for one tune is distributed to the receiving device. If there are a plurality of pieces of music data to be transmitted (here, ten pieces of music data), other music data is also distributed as described above. However, in this case, after the content information 200 is first distributed for 10 songs,
It is assumed that the content data 300 is distributed for 10 songs.

When the distribution uses the carousel method, the process from the distribution of the content information 200 to the end of the distribution of the content data 300 is repeated within a predetermined time (FIG. 5: S502 → S504 Yes).

The processing up to the distribution of the music data by the transmitting apparatus 101 has been described above.

[Data Reception Processing in Receiving Apparatus] Next, a method of processing the content information 200 and the content data 300 distributed by the transmitting apparatus 101 in the receiving apparatus 131 will be described.

When the broadcast receiving means 135 constituting the receiving apparatus 131 receives the content information 200 via the broadcast distribution path 121, the broadcast receiving means 135 transmits the received content information 200 to the broadcast reception control means 134. Next, the broadcast reception control means 134 transmits the content information 20
0 to the error detecting means 141 and the error detecting means 1
41 checks whether the content information 200 is normally received using the error correction code 312 (FIG. 6: S601).

When the content information 200 has been normally received, the error detecting means 141 stores the content information 200 in the packet storage means 139. It should be noted that the content information 200 determined to have not been received normally is discarded.

Also, a plurality of content data 300 distributed following the content information 200 are transmitted from the broadcast reception control means 134 to the error detection means 141 in the same manner as described above.
After normal reception is confirmed using the error correction code 335, the packet is stored in the packet storage unit 139 (FIG. 6: S602 → S603).

When the content is distributed by the carousel method, the content information receiving process (S601)
The packet storage processing (S603) is repeated a predetermined number of times.

Next, the broadcast reception control means 134 determines the transmission end time 31 stored in the content information 200.
1, if it is determined that the data distribution using the carousel method has been completed, the packet (content information 200
Then, the lack of the content data 300) is detected (FIG. 6: S604). The end of the data distribution is confirmed at the transmission end time 311 included in the content information 200, for example.

The lack of the content information 200 corresponds to the content identifier 331 included in the content data 300.
May be determined based on the lack of the content information corresponding to. When a plurality of pieces of content information 200 are transmitted, the determination may be made based on the lack of the content identifier 301 assigned with a serial number.

The lack of the content data 300 is determined by, for example, referring to the content identifier 301, the data size 304, and the number of packets 305 included in the content information 200, and calculating the total number of the corresponding content data 300 and the total of the data 344. Can be detected. Here, the content data corresponding to the content information 200 indicates content data having a content identifier 331 that matches the content identifier 301.

When the missing of the content data is detected, it is possible to know which content data is missing by referring to the packet identifier 332 assigned with the serial number.

In the detection of the packet loss, if all the received packets are normal, the content identifier 301 of each music data is used as the data reconstructing means 133.
(FIG. 6: S604 Yes). Upon receiving the content identifier 301, the reconfiguration unit 133 sends the content information 200 and the content data 3 corresponding to the content identifier 301 from the packet storage unit 139.
00 is read, and music data is configured based on the content information 200 and the content data 300 (FIG. 6: S611).

The music data constituted by the data reconstructing means 133 is transmitted to a reproducing device 132 such as a television, a radio, a stereo, etc. as necessary, and the reproducing device 132 reproduces the received music data. Also,
The data is stored in a storage unit (not shown) as needed, and is read and reproduced according to a user's instruction.

The above is the processing from reception of the music data of the receiving device 131 to reproduction of the music data.

[Selection Processing in Receiving Apparatus] Subsequently, when a packet is received by the receiving apparatus 131 but the packet is not in a normal state, or when the packet itself cannot be received, the packet is Missing packets result. Particularly in mobile terminals such as automobiles and mobile phones, it can be easily expected that frequent lost packets will occur when entering a tunnel or underground shopping mall.

Therefore, in order to obtain the missing packet, the receiving device 131 transmits a retransmission request, which is a request for transmitting a missing packet, to the transmitting device 101.

However, music data having missing packets,
That is, when retransmission requests are transmitted for all incomplete music data, it is expected that a huge load will be applied to the transmission device 101. Further, a user who intends to acquire music data using the receiving device 131 does not necessarily need (want) all music data. Therefore, before the receiving apparatus 131 transmits the retransmission request to the transmitting apparatus 101, a selection process of selecting music data to which the retransmission request is to be transmitted is performed.

The data selecting means 142 of the receiving device 131 is provided with the contents information 200 and the contents data 3 already received from the packet storing means 139.
00, for example, the distribution data list 70 shown in FIG.
0 (FIG. 8: S801). The distribution data list 700 includes a content identifier 301, a song name 701 obtained from the content name 302, and an artist 70
2, data size 304, additional information 703, received data amount 704, missing data information 705, download status 7
06. The received data amount 704 is obtained by summing up the data 334 of normally received packets. The missing data information 705 indicates which content data is missing, for example, the packet identifier 33.
2 is stored. The additional information 703 includes part or all of the information included in the additional information 320, but is not always necessary here.

The download status 706 indicates, for example, the state of the music data corresponding to the content identifier 301 (download completed, missing packet, etc.).

Next, the data selecting means 142 obtains Dr, which is the difference between the data size 304 and the received data amount 704, for each music data (contents having different content identifiers 301) (FIG. 8: S802).

Subsequently, the data selecting means 142 outputs
Is determined (FIG. 8: S803).

Here, if Dr = 0, since all the content data have been normally downloaded and can be reproduced, the data selecting means 142 inputs the fact to the download status 706, for example ( Figure 8: S
803 → S804). Here, it is assumed that “○” is input to the download status 706 of the content that can be reproduced.

If 0 <Dr <= Df # max, music data can be reproduced without any problem by downloading a certain number of missing packets. "
Is input (FIG. 8: S803 → S805). However, the content information 20 of the music data targeted for the retransmission request
If the information indicating that the retransmission request is not permitted is stored in the retransmission request permission 308 in 0, the input of “△” in the download status 706 is not performed.

The Df_max is a value of the delivery (transmission) when a missing packet is received after a retransmission request described later is made.
Indicates the maximum value of the data amount of missing data to be created. That is, D
When f # max is large, for example, a retransmission request can be made even when most of the music data cannot be received by broadcasting. When Df # max is small and music data has not been sufficiently received by broadcasting, a retransmission request cannot be made. The Df # max can be set freely by the user or, for example, the data selection unit 142 in the receiving device 131.

When Dr> Df # max, the data amount of the missing packet is larger than the maximum value of the data amount of the missing data to be distributed (distributable). Do not enter anything.

The above Dr is determined for each music data.
When the input for the download status 706 is completed, the data selection unit 142 sets the distribution data list 70
0 is reconfigured to create a distribution data list 900 shown in FIG. 9 (FIG. 8: S806). The term “reconstruction” used herein refers to deleting a list of music data for which no input has been made in the download status 706.

For example, the distribution data list 7 shown in FIG.
00, the reproducible music data are “A001”, “A
006 "and" A009 ", and the music data for which retransmission request is possible are" A004 "," A005 "," A00 ".
8 ".

In this example, the data selecting means 142
Means that the broadcast reception control means 134 outputs “A” and “△” in the download status 706,
001 "," A004 "to" A006 "," A00
8 ", distribution data list 900 having" A009 "
(FIG. 9) is created. However, when a retransmission request to be described later is not made, the distribution data list 900 may be created only from data in which “○” is input in the download status 706, that is, data having no missing data.

Subsequently, the data selection means 142 includes, for example, a display provided in the reception device 131,
The distribution data list 90 for the connected television etc.
0 is displayed as it is or only necessary items are extracted and displayed (FIG. 8: S807).

FIG. 10 shows an example of the above display. Here, the download status 706 of the distribution data list 900, the content identifier 3
01, a song title 701, and an artist 702 are displayed as a download song selection screen 1002. Note that conventional television broadcasts and the like are displayed in the TV program display area 1001.

When the distribution data list 900 is displayed, the user selects required music data from the music data displayed on the distribution data list 900 (FIG. 8: S808). Since the music data indicated by “○” can be reproduced, the music data to be selected is “△”. Here, the above selection may be performed by, for example, a remote controller, or the user may touch the TV screen 1000 configured as a touch panel.

When the user selects the music data, the data selecting means 142 changes the display of the download status 706 of the music data to “▲”, for example. When the user selects (presses) the display of the download 1003, for example, the information of the download status 706 corresponding to the user's selection in the distribution data list 900 is also changed to “▲”. When the distribution data list 900 is created from only data having no missing data, the user selects, for example, only necessary data,
Unnecessary data can be deleted immediately without storing it in the receiving device. Naturally, the data selected by the user does not include the missing data and can be reproduced immediately.

When the selection of the music data to be downloaded (complementing the missing packet) is completed, the data selecting means 142
Transmits a missing packet of music data corresponding to the user's selection to the retransmission request control means 138 (FIG. 8: S80).
9). Here, the missing packet can be represented by combining the packet identifier 332 stored in the missing data information 705 of the distribution data list 900 with the content identifier 301.

As described above, in the receiving apparatus, by using the predetermined threshold value (here, Df # max), the content that includes a large number of missing packets and takes a long time to supplement the missing packets is previously excluded from the target of the retransmission request. By doing so, it is possible to reduce the load on the transmitting apparatus 101, for example, when complementing a lost packet using a bidirectional communication path described later. Further, since the time required for complementing the content selected as the complement target is short, it is possible to reduce the financial burden when the user uses the two-way communication path.

Further, by displaying the content to be complemented and allowing the user to select only the necessary content, unnecessary content is not complemented, so that the load on the transmission device can be further reduced. Becomes

Note that after a content containing a lot of missing packets is previously excluded from retransmission request targets using a predetermined threshold value, a retransmission request may be automatically made without performing a process for allowing the user to select.

[Retransmission Request Processing in Receiving Apparatus]
The retransmission request processing performed by the retransmission request unit 138 will be described in detail. When the packet identifier of the missing packet and the content identifier corresponding to the packet identifier are received from the data selection unit 142, the retransmission request control unit 138 sends the retransmission of the missing packet to the transmitting device 10.
Request 1 At this time, the retransmission request is transmitted via a two-way communication channel 122 such as a telephone line or the Internet.

FIG. 11 shows an example of the format of a packet used for the retransmission request. In FIG. 11A, the receiving apparatus identifier 1 constituting the packet 1100
101 is a value that can uniquely identify the receiving device 131 that makes a retransmission request. Specific examples include an address (IP address) and a telephone number. The request type 1102 is
The content, type, format, and the like of the retransmission request are shown, but the details will be described later. The retransmission waiting time 1103 indicates the time during which the receiving apparatus that has made the retransmission request waits for retransmission of the packet specified by the packet identifier 1105. Therefore, the receiving apparatus waits for retransmission until the time when the transmitting apparatus receives the retransmission request and the retransmission waiting time 1103 is added. In the packet 1110 in FIG. 11B, a retransmission wait end time 1111 is specified instead of the retransmission wait time 1103. The content identifier 1104 and the packet identifier 1105 indicate a packet to be retransmitted by the transmitting device, and correspond to the content identifier 331 and the packet identifier 332 in the content data 300, respectively. A predetermined packet can be uniquely specified by using two of the content identifier 1104 and the packet identifier 1105. However,
When the packet identifier 1105 includes information that can also identify the content, the content identifier 114 is not necessarily required.

FIG. 11 (a) or FIG. 11 (b)
In addition to making a retransmission request for each packet as shown in (1), by providing a packet number 1121 and a plurality of packet identifiers 1122 as shown in a packet 1120 in FIG. May be. As shown in a packet 1130 in FIG.
By providing 2, a plurality of consecutive packets may be designated.

As described above, by designating a plurality of packets collectively and making a retransmission request, it is possible to reduce the number of retransmission request packets themselves.

Although FIG. 11 shows a typical example of the format of a packet for a retransmission request, the above-described method for specifying a retransmission waiting time and the method for specifying a packet can be arbitrarily combined. A plurality of packet designation methods may be used in combination. in this case,
The content of the retransmission request is identified by the information of the request type 1102.

When the packet identifier of the missing packet and the content identifier corresponding to the packet identifier are received from the data selection unit 142, the retransmission request control unit 138 requests the transmission device 101 to retransmit the missing packet. .

At this time, “0” is added to the retransmission waiting time 1103.
Indicates that retransmission is requested immediately. A number other than “0” set in the retransmission waiting time 1103 is a time during which the receiving apparatus 131 waits for reception of a retransmission packet, for example, “5 minutes” or “15”.
(FIG. 12: S1202). The waiting time may be determined by a user's input, or a predetermined number may be input in advance.

After the retransmission request control means 138 sets the retransmission waiting time 1103, the retransmission request transmission means 1
37 transmits, for example, the packet 1100 shown in FIG. 11 to the transmitting apparatus 101 via the two-way communication path 122 (FIG. 12: S1203). At this time, the transmitting apparatus 101 is determined based on the retransmission request destination 309 included in the content information 200.

After the receiving apparatus 131 has transmitted the retransmission request, for example, if an invalid packet identifier or an invalid content identifier is specified, if the specified packet is not permitted to be retransmitted, If the total size of the packets is too large: If the specified packet is not already transmittable, etc., the transmitting device 101 transmits a request rejection notification response.

In such a case, the response is received by the retransmission request control unit 138 via the response reception unit 136, and the retransmission request control unit 138 ends the processing of the retransmission request (FIG. 12: S1204 Yes → S1205).

It is to be noted that the transmitting apparatus 101 responds to the retransmission request.
When a response to the retransmission request is transmitted from the retransmission request control unit 138, the retransmission request control unit 138 stores the content of the received retransmission request in the retransmission request storage unit 140 (FIG. 12: S1).
204No → S1206).

Subsequently, when the missing packet corresponding to the retransmission request is transmitted via the broadcast distribution path 121, the packet storage means via the broadcast receiving means 135, the broadcast reception control means 134, and the error detecting means 141 139. However, the lost packet received by the retransmission request control means 138 is checked before the storage, and if there is information on the corresponding lost packet in the retransmission request storage means 140, the information is deleted. (Fig. 1
2: S1207 → S1209).

When the retransmission request control unit 138 refers to the retransmission request storage unit 140 at a predetermined timing and finds a packet that has not been transmitted (cannot be received) even after the predetermined retransmission waiting time 1103 has elapsed, A retransmission request is transmitted again to the transmitting apparatus 101 (FIG. 12: S1
208 → S1209). Here, when the missing packet corresponding to the retransmission request is transmitted via the two-way communication channel 122, it is stored in the packet storage unit 139 via the response receiving unit 136. However, similarly to the above, before the storage, the retransmission request control unit 138 checks the missing packet received, and the retransmission request storage unit 140
If there is information on the corresponding missing packet, the information is deleted (FIG. 12: S1211 → S120).
9).

It is to be noted that which of the broadcast distribution path 121 and the two-way communication path 122 the missing packet is received by the receiving apparatus 131 determines whether the transmitting apparatus 1
01 will be described.

When the receiving device 131 receives the missing packet, the data reconstructing means 131 reconstructs the music data.

The music data constituted by the data reconstructing means 133 is transmitted to a reproducing device 132 such as a television, a radio, a stereo, etc., as necessary, and the reproducing device 132 reproduces the received music data. Also,
The data is stored in a storage unit (not shown) as needed, and is read and reproduced according to a user's instruction.

As described above, the receiving device stores the retransmission request in the retransmission request storage means and confirms the reception of the missing packet from the transmitting device, thereby reliably recognizing the missing packet that has not been received. However, it is possible to reliably receive a missing packet via a bidirectional communication path described later.

[Retransmission processing in transmitting apparatus] Now, the retransmission request from the receiving apparatus 131 is transmitted to the retransmission request receiving means 10.
7, first, the retransmission control unit 108
Check the content of the received retransmission request.

Here, if the retransmission request is: • an invalid packet identifier or an invalid content identifier is specified; • if the specified packet is not allowed to be retransmitted; • the total size of the specified packet is large. If the specified packet cannot be transmitted, the request rejection notification is transmitted to the receiving device 131 via the response means 106 and the two-way communication path 122, and the retransmission processing is ended (FIG. 13). : S1303 Yes → S1304).

As described above, by rejecting a retransmission request for a retransmission request determined to be unsendable on the transmitting device side, unnecessary retransmission waiting at the receiving device can be avoided.

If there is no problem with the retransmission request, the retransmission control means 108 transmits a request acceptance notification corresponding to the retransmission request to the receiving device 131 via the response transmission means 106 and the two-way communication path 122. (FIG. 13: S1303
No → S1305). Subsequently, the retransmission control unit 108
Stores the received retransmission request in the retransmission request storage unit 110.

Next, after a lapse of a predetermined time, the retransmission control means 1
08 collects the retransmission requests received from the plurality of receiving devices and stored in the retransmission request storage unit 110, and
21 or the two-way communication channel 122 to determine whether to retransmit the packet (FIG. 13: S1306).

The following is a specific example of the counting method.
The retransmission control unit 108 reads the retransmission request stored in the retransmission request storage unit 110 at a predetermined timing, and creates, for example, a graph 1400 shown in FIG.
The graph 1400 shows, for each content (music data),
This is a visual representation of a retransmission request for a packet constituting the content. For example, the content A1401 (music data A) is composed of 2,000 packets to which packet identifiers “0001” to “2000” are assigned. Also, from this graph, the content A is constructed,
It can be read that there are about seven retransmission requests for the packet with the packet identifier = “0001” and about 780 retransmission requests for the packet with the packet identifier = “2000”.

From the total result, for example, the content B
It can be determined that there are many retransmission requests for the packets making up the 1404, and few retransmission requests for the packets making up the content C1405.

Here, the packets constituting all the contents may be distributed via the broadcast distribution channel 121,
Naturally, since different contents (for example, contents X, contents Y, etc.) have already been transmitted, the contents A to C
It is not possible to use the broadcast distribution path 121 only for the purpose.

Therefore, based on the current usage status of the broadcast distribution channel 121 and the graph 1400, the retransmission control means 108 determines that the predetermined threshold value, for example, the number of retransmission request packets is 400 or more (the packets constituting the content B). , And a packet constituting the content A, the packet 1403 having a packet identifier of “0700” to “2000”)
Select

The content identifier 331 and the packet identifier 332 corresponding to the selected packet are transmitted to the broadcast transmission control means 104 by the retransmission control means 108.

The broadcast transmission control means 104 reads out the packet corresponding to the received content identifier 311 and packet identifier 332 from the packet storage means 109, and again receives the packet through the broadcast transmission means 105.
1 (FIG. 13: S1307).

Receiving apparatus 131 which has received the retransmission packet via broadcast distribution path 121 reconstructs the data in the same manner as the reception processing shown in FIG.

When retransmitting a packet via the broadcast distribution path 121, it is also possible to perform a process of prioritizing retransmission with the shorter retransmission waiting time 1103 indicated by the receiver 131.

By the way, packets having the packet identifiers of “0001” to “0699”, which are packets constituting the content C or less and packets constituting the content A and having a packet identifier of “0001” to “0699”, are broadcasted. It is not distributed from the road 121. In this case, the retransmission request control unit 138 included in the receiving device 131 refers to the retransmission request storage unit 140 and transmits, for example, the retransmission request collectively again for the packets exceeding the retransmission waiting time. When the transmitting apparatus 101 receives the retransmission request again via the bidirectional communication path 122, the transmitting apparatus 101 stores the packet corresponding to the retransmission request using the bidirectional communication path 122 in the packet storage unit 109. Read out,
The transmission is performed via the bidirectional communication path 122 (FIG. 13: S13).
08 → S1309).

The bidirectional communication path 122, response receiving means 1
The retransmission request control unit 138 that has received the retransmission packet via the P.36 deletes the information of the corresponding missing packet in the retransmission request storage unit 140 and stores the received packet in the packet storage unit 139. Thereafter, the music data in which all the packets have been collected is stored in the data reconstructing means 133.
, And are transmitted to a reproducing device 132 such as a television, a radio, or a stereo as required, and reproduced.

As described above, by selecting a transmission path to be used for retransmission based on a retransmission request from a receiving apparatus, for example, packets that need to be retransmitted in large quantities are transmitted from a broadcast transmission path, It is possible to perform retransmission, such as transmitting a packet that does not cause any problem in the retransmission of the packet from the bidirectional communication path. As a result, waste that can occur in retransmission using the broadcast distribution path, that is, effective use of the broadcast distribution path by minimizing retransmission using the broadcast distribution path for packets addressed to a small number of receivers is considered. It becomes possible. In addition, it is possible to solve the problem of securing the line, the problem of preparing the line capability more than necessary, and the preparation of the processing capability, which may occur in the retransmission using the bidirectional communication path.

Also, the receiving apparatus can reduce the line usage fee as compared with the case where a large amount of missing packets are all obtained by using the two-way communication path, and can reliably obtain necessary contents. become.

In the first embodiment, the missing packet is transmitted using the bidirectional communication path in response to the second retransmission request from the receiving apparatus. On the other hand, retransmission using a broadcast distribution path and retransmission using a bidirectional communication path may be selected.

Also, in the first embodiment, music data has been described as an example of content, but moving images, still images,
It may be character data, voice data, a program, or the like. (Embodiment 2) Next, Embodiment 2 of the transmitting apparatus, the receiving apparatus, and the transmitting / receiving system according to the present invention will be described. In the second embodiment, based on the first embodiment,
The receiving device 131 allows the user to specify a retransmission route.

That is, when confirming whether all the packets in FIG. 6 are normal or not (S604), the receiving apparatus 131 displays the abnormal content (music data) if it is not normal, for example, for each content. It prompts the user to select a retransmission route.

FIG. 16 shows a display example for prompting the user to select the retransmission route.
Shown in FIG. 16 is an input screen 1600 for inputting a user's instruction for content that can be downloaded according to a predetermined threshold using the download status 706 of the distribution data list 700 shown in FIG. 7, for example. The data is displayed by the data selection unit 142.

On the input screen 1600, the title 701 of the content having the missing packet (here, the title 4) is displayed.
One of the buttons 1601 to 1603 can be selected.

As the user's judgment information, the ratio of the normally received data to the entire contents and the data amount 1604 of the missing packet, the expected waiting time 1605 until the completion of the reception, and the case where the two-way communication path 122 is selected for the reception. And the like are displayed.

When the user selects, for example, “ignore” 1601 on the input screen 1600, there is no request to retransmit the missing packet of the content.
The normally received packet stored in the packet storage unit 139 is deleted after a predetermined time has elapsed. However, when a missing packet is received via the broadcast distribution path 121 due to a retransmission request of another user or the like, the content may be stored as a normally received content.

For example, when the user selects “request retransmission” 1602 on the input screen 1600,
As a request for retransmission via the broadcast distribution path 121, a request for retransmission of a missing packet is transmitted to the transmitting apparatus 101 (FIG. 1).
5: S1501 Yes → S1502 → S1503). Specifically, for example, the packet 1100 in which the “broadcast distribution channel” is input as the request type 1102 is transmitted to the retransmission request control unit 138.
Is transmitted to the transmission control means 108 via the two-way communication path 122.

Transmitting apparatus 101 that has received the retransmission request
Stores the retransmission request in the retransmission request storage unit 110, aggregates the retransmission request, and transmits the retransmission request from the broadcast distribution channel 121, as in the first embodiment. It is not always necessary to reject a retransmission request or set a waiting time.

Subsequently, the receiving device 131 receives the missing packet via the broadcast path 121 (FIG. 15: S
1504). However, retransmission via the broadcast distribution channel is not always performed. The receiving device 131 that has received the missing packet via the broadcast distribution channel 121 can reproduce the content by reconstructing the data, as in the first embodiment (FIG. 15: S1504 → S611).

If the user selects, for example, “Reacquire Immediately” 1603 on the input screen 1600, a request for retransmission of a lost packet is sent to the transmitting apparatus 101 as a request for retransmission via the bidirectional communication path. (Figure 1
5: S1501 No → S1505 → S1506). Specifically, for example, the packet 1100 in which the “two-way communication path” is input as the request type 1102 is transmitted to the retransmission request control unit 138.
Is transmitted to the transmission control means 108 via the two-way communication path 122.

In this case, in response to the retransmission request, if an invalid packet identifier or an invalid content identifier is specified; if the specified packet is not permitted to be retransmitted; If the retransmission request is rejected, the missing packet is not received (FIG. 15: S1507 Yes → S).
1508).

If the retransmission request is not rejected, the missing packet indicated in the retransmission request is received via the two-way communication channel 122 (FIG. 15: S1507 No → S150)
9).

Receiving apparatus 131 that has received the missing packet via bidirectional communication path 122 can reproduce the content by reconstructing the data as in the first embodiment (FIG. 15: S1509 → S611). .

As described above, by allowing the receiving apparatus to select the path at the time of retransmission of a lost packet, for example, a content that is not important to the user may not be able to be received, but is not a paid broadcast path. Receive using
It is possible to make a selection according to the degree of importance such that important contents are securely received using a two-way communication path even if they are charged.

In addition, the user selects a two-way communication path when entering the underground shopping mall where the broadcast does not reach, for example, and selects a broadcast distribution path when the user can receive the broadcast. Other choices are also possible. (Embodiment 3) Next, Embodiment 3 of the transmitting apparatus, the receiving apparatus, and the transmitting / receiving system according to the present invention will be described. The third embodiment is based on the first embodiment,
A mechanism for changing the communication quality of the broadcast communication path according to the total of the retransmission requests will be described.

First, FIG. 17 shows the transmitting apparatus 101.
6 is a graph showing the number of retransmission requests totaled by the retransmission control unit 108 which constitutes FIG. The horizontal axis of the graph indicates the transmission time of the packets constituting the content, and the vertical axis indicates the number of retransmission requests for each packet. That is, line 1
Reference numeral 704 indicates a change in the retransmission request over time.

[0139] The data rate 1703 indicates the data rate when transmitting the content via the broadcast distribution channel 121. Here, the data rate indicates the ratio of the data constituting the content to the entire packet. For example, by reducing the data rate and increasing the error correction code, the probability that the receiving apparatus can correct the error of the received packet increases. That is, transmission quality is improved. In addition, by increasing the data rate and decreasing the error correction code, the probability of correcting an error decreases, but the transmission efficiency can be improved.

The upper limit 1001 is an upper limit for changing transmission conditions, and the lower limit 1702 is a lower limit for changing transmission conditions, which will be described in detail later.

The number of retransmission requests is between the upper limit 1701 and the lower limit 1702 from immediately after the start of broadcasting at a data rate of 80% until time 1705. However, from time 1705 to time 1706, the number of retransmission requests exceeds the upper limit 1701. Here, an increase in the number of retransmission requests indicates that transmission quality may be poor. For this reason, for example, it is necessary to secure the number of lines capable of processing the large number of retransmission requests and to secure the processing capacity and the bandwidth.

In order to solve the above problem, the retransmission control means 108 receives a retransmission request, and if the number of retransmission requests is larger than the upper limit, the retransmission control means 108 (or the packet generation means 103) On the other hand, an instruction to decrease the data rate is issued (FIG. 18: S1801 → S1802 Yes → S1).
803).

Broadcast transmission control means 104 receiving the above instruction
Transmits the content at a data rate of 60%, for example.

As described above, the transmission efficiency is reduced by lowering the data rate, but the transmission quality can be improved. That is, retransmission requests are reduced by lowering the data rate.

Also, for example, from time 1707 to time 170
Up to 9, the number of retransmission requests is below the lower limit 1702. Here, the fact that the number of retransmission requests has decreased means that
It can be said that the transmission efficiency is poor. Therefore, the retransmission control unit 108 instructs the broadcast transmission control unit 104 to increase the data rate (FIG. 18: S1804 Yes → S180).
5).

Broadcast transmission control means 104 receiving the above instruction
Transmits the content at a data rate of 70%, for example.

Note that the upper limit value can be automatically maintained at a data rate according to the system by determining the number of lines for processing the retransmission request, the processing capacity, the bandwidth, and the like.

As described above, by dynamically changing the data rate of the content using the broadcast channel based on the retransmission request, it becomes possible to maintain the optimum transmission efficiency and transmission quality.

It is not always necessary to immediately reflect the number of retransmission requests in transmission conditions. The number of retransmission requests is stored as transmission result information, and can be used as highly reliable data when constructing a transmission path network or improving a transmission method. (Embodiment 4) Next, Embodiment 4 of the transmitting apparatus, the receiving apparatus, and the transmitting / receiving system according to the present invention will be described. Embodiment 4 is based on Embodiment 1 described above,
A mechanism for referring to a rating according to the total of retransmission requests will be described.

FIG. 19 is an example of a graph showing the audience rating of the content calculated by the reception status totalizing means 111 based on the number of retransmission requests. The vertical axis of the graph 1900 indicates the packet transmission time, and the horizontal axis indicates the audience rating calculated from the number of retransmission requests for the packet transmitted at the corresponding time. The retransmission request is transmitted from the receiving device 131 to the transmitting device 101 via the two-way communication channel 122.

The transmission / reception of the retransmission request is described in detail in the first embodiment. However, as described in the first embodiment, the retransmission request is transmitted from the receiving device only when the reception of the broadcast packet has failed.

Therefore, the number of retransmission requests does not reflect the number of receiving devices that have received transmission data.

In order to reliably receive the retransmission request from the receiving device, the reception status totalizing means 111 instructs the broadcast transmission control means 104 to transmit the unreceivable packet. The unreceivable packet is a packet that is not transmitted or a packet that includes incorrect data. The unreceivable packet may be generated based on predetermined conditions, for example, at certain time intervals or at certain number of packets.

Information on the transmitted unreceivable packet is stored in, for example, a storage unit (not shown). Subsequently, the cause of the retransmission request can be identified by comparing the packet identifier specified in the retransmission request received from the receiving device 131 with the information of the unreceivable packet. That is, the number of retransmission requests for a packet that cannot be retransmitted indicates the number of receiving apparatuses that have required reception of the packet, and the audience rating of the packet can be obtained by dividing by the total number of receiving apparatuses.

The audience rating 1903 in FIG. 19 is a graph showing the audience rating obtained by generating unreceivable packets at regular time intervals in a time-series manner. In FIG. 19, the audience rating corresponding to the transmission content 1901 and the transmission time 1902 can be referred to.

As described above, by transmitting unreceivable packets at a predetermined timing, it is possible to ascertain the content reception status (audience rating) from the number of retransmission requests received. (Fifth Embodiment) Next, a fifth embodiment of the transmitting apparatus, the receiving apparatus, and the transmitting / receiving system according to the present invention will be described. In the fifth embodiment, based on the first embodiment,
A mechanism for charging content using a retransmission request will be described.

FIG. 20 shows the transmitting apparatus 101 and the receiving apparatus 1
31 shows an example of communication transmitted and received with respect to a retransmission request. The user 2001 is a user of the receiving device 131.

First, billing means 112 constituting transmitting apparatus 101 transmits the unreceivable packet generated by transmitting apparatus 101 using, for example, broadcast transmission control means 104. Receiving device 131 that has received the unreceivable packet
Transmits a retransmission request 2003 for the unreceivable packet.

The retransmission request 2003 is transmitted from the receiving apparatus 131 to the transmitting apparatus 10 according to the procedure described in the first embodiment.
1 is transmitted. Receiving the retransmission request 2003, the charging unit 112 included in the transmitting apparatus 101 transmits an authentication request 2004 in response to the retransmission request 2003.
Note that the authentication request 2004 is a notification requesting to return information for identifying the receiving device that has made the retransmission request.

Upon receiving the authentication request 2004, the accounting support means 143 constituting the receiving device 131 issues an authentication request 2005 to the user 2002. The authentication request 2005 is, for example, an operation to prompt input of a password or a user ID.

Subsequently, for example, the password or the user ID input by the user 2002 is transmitted to the authentication response 2006.
Is transmitted from the receiving apparatus 131 to the transmitting apparatus 101.

However, in response to the authentication request 2004, an authentication response is made by using information held by the receiving device 131, for example, identification information of the receiving device, or set user information and key information for data reception. Is possible, the authentication response 2006 may be transmitted without performing the authentication request 2005 and the authentication response 2006 for the user.

Billing means 1 constituting transmission apparatus 101
06 determines that the authentication response 2006 is appropriate,
A billing notification 2008 is transmitted to the receiving device 131. However,
If it is determined that the authentication response 2007 is invalid, a retransmission request rejection notification is transmitted in the retransmission response 2020 without performing the charging procedure 2015 including the charging notifications 2008, 2009 and the charging response 2010, and the process ends. .

[0164] The billing notice 2008 includes the usage fee and payment method of the pay data. The receiving device 1
31 sends a billing notification 2009 to the user 2001. The billing notification 2009 is an operation for notifying the user of the billing information presented from the receiving device 2000 and prompting the user to select whether or not to make a payment and to input information necessary for the payment. Subsequently, the charging response 2010 input by the user 2001 is transmitted to the transmitting device 101.

If the billing acceptance or payment information has been set in advance for the receiving device 131, the billing response 2011 may be transmitted without performing the billing notification 2009 and the billing response 2010 to the user. Absent. When determining that the charging response 2011 is appropriate, the transmitting apparatus 101 transmits a request acceptance notification corresponding to the retransmission request 2003 to the receiving apparatus 131 as a retransmission response 2020.

Subsequently, the receiving apparatus 131 transmits the retransmission data 2013 specified by the retransmission request 2003, and ends the processing. The receiving device 131 transmits the retransmission response 201
When retransmission request acceptance is notified in 2, retransmission data waiting is performed, all retransmission data 2013 is received, and the process is terminated. In the case of non-paid data, charging procedure 20
The transmission of the retransmission response 2020 and the retransmission data 2013 is performed after the authentication response 2006 without performing step 15.

It should be noted that the authentication request 2004,
By performing the authentication procedure 2014 including the authentication response 2006 and the authentication response 2006, the transmitting apparatus 101 can obtain detailed information of the receiving apparatus 131, and can be used, for example, as a part of the audience rating survey described in Embodiment 4. .

[0168] Alternatively, based on the obtained information of the receiving device, the reception can be restricted under a predetermined condition.
For example, it is possible to allow only a specific model to receive the control program of the receiving device, or to allow age-restricted data to be received only by users who are older than the restricted age.

In FIG. 20, the retransmission data 2013 is transmitted using the bidirectional communication path 122, but the broadcast distribution path 121 may be used. When pay data is to be retransmitted by a broadcast channel, the retransmission data 2013 is encrypted, and key information for decryption is notified by a retransmission response 2012. Can be realized. The authentication procedure 20
14 and the accounting procedure 2015 may be realized by one request and one response.

As described above, the transmitting apparatus operates the content and generates a retransmission request from the receiving apparatus, so that the receiving apparatus can be authenticated, the distribution destination can be restricted, and charged data can be charged. (Embodiment 6) Next, Embodiment 5 of the transmitting apparatus, the receiving apparatus, and the transmitting / receiving system according to the present invention will be described. Embodiment 6 is based on Embodiment 1 described above,
A configuration provided with a broadcast distribution channel and a bidirectional communication channel will be described.

FIG. 21 shows a data distribution system using a transmission / reception device capable of transmitting and receiving data to and from a broadcast distribution channel. The transmitting / receiving apparatuses 2102 to 2104 are the same as those in FIG.
Means 103 to 1 of the transmitting apparatus 101 and the receiving apparatus 131
10 and a transmission / reception device having means 133 to 142.

The transmission / reception devices 2102 to 2104 can transmit and receive using the broadcast distribution channel 121 and are interconnected by a bidirectional communication channel 122.
For example, the transmission / reception apparatus 2102 is used for the broadcast distribution path 121.
Can be used to broadcast data to the transmitting / receiving apparatuses 2103 and 2104. Broadcast transmission and reception of data use the procedure described in the first embodiment. Similarly, according to the procedure described in the first embodiment, the transmitting / receiving device 21
Numerals 03 and 2104 receive the broadcast data and request retransmission of the failed data via the communication path 2101. The retransmission data is transmitted on the broadcast path 2100 or the communication path 210.
1 transmitted.

The above-described broadcast transmission, retransmission request, and data retransmission are performed by transmitting / receiving apparatus 2103 and transmitting / receiving apparatuses 2102, 210
4, the transmission / reception device 2104 and the transmission / reception device 210
The same operation is performed between 2, 2103.

There is no limitation on the number of transmission / reception devices constituting the data distribution system, and a network using a broadcast path and a communication path is constructed between an arbitrary number of transmission / reception devices.
Each transmission / reception device transmits a large amount of data or broadcast data using the broadcast distribution channel 121, and transmits data supplementing the broadcast transmission and individual data between the devices to the bidirectional communication channel 1.
By transmitting data using the H.22, efficient data transmission / reception can be realized.

As described above, by using the transmission / reception device, it is possible to construct a transmission network for efficiently and flexibly distributing data by selectively using the broadcast communication channel and the bidirectional communication channel.

[0176]

As described above, in the receiving apparatus, by using a predetermined threshold value, by excluding in advance from the target of the retransmission request, the content that includes a large number of missing packets and takes a long time to supplement the missing packets, for example, It is possible to reduce the load on the transmission device when complementing a lost packet using a bidirectional communication path described later. Further, since the time required for complementing the content selected as the complement target is short, it is possible to reduce the financial burden when the user uses the two-way communication path.

Furthermore, by displaying the content to be complemented and allowing the user to select only the necessary content, the unnecessary content is not complemented, so that the load on the transmission device can be further reduced. Becomes

Further, by specifying a plurality of packets collectively and making a retransmission request, it becomes possible to reduce the number of packets for the retransmission request.

Further, the retransmission request is stored in the retransmission request storage means, and the reception of the missing packet from the transmitting device is confirmed, so that the missing packet that has not been received is reliably recognized, and the bidirectional communication path is established. It is possible to reliably receive the missing packet through the communication.

In the transmitting apparatus, by selecting a transmission path to be used for retransmission based on a retransmission request from the receiving apparatus, for example, packets that need to be retransmitted in large quantities are transmitted from the broadcast transmission path, It is possible to perform retransmission such that a packet that does not cause any problem with a small amount of retransmission is transmitted from the bidirectional communication path. As a result, waste that can occur in retransmission using the broadcast distribution path, that is, effective use of the broadcast distribution path by minimizing retransmission using the broadcast distribution path for packets addressed to a small number of receiving terminals is considered. It becomes possible. Further, it is possible to solve the problem of securing a line, the problem of preparing more line capacity and processing capacity than necessary, which may occur in retransmission using a bidirectional communication path, and the like.

Also, the receiving device can reduce the line usage fee as compared with the case where a large amount of missing packets are all obtained by using the bidirectional communication path, and can reliably obtain necessary contents. become.

Furthermore, by making it possible for the receiving apparatus to select a route at the time of retransmission of a lost packet, for example, a content that is not important to the user may not be able to be received but a broadcast route that is not charged is used. It is possible to make a selection according to the degree of importance such that important contents are reliably received using a two-way communication path even if the contents are charged. In addition, when the user enters an underground shopping mall where a broadcast does not reach, for example, a bidirectional communication path is selected, and a broadcast distribution path is selected if the broadcast can be received. It is possible.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a schematic configuration of a transmitting device and a receiving device.

FIG. 2 is a configuration example of a content information packet.

FIG. 3 is a configuration example of a content data packet.

FIG. 4 is an image diagram at the time of distribution when music data is divided.

FIG. 5 is a flowchart at the time of data transmission in a transmission device.

FIG. 6 is a flowchart of a data receiving process in the receiving device.

FIG. 7 is an image diagram showing an example of a distribution data list.

FIG. 8 is a flowchart of a selection process in a receiving device.

FIG. 9 is an image diagram showing an example of a distribution data list after processing;

FIG. 10 is an image diagram showing an example of a download music selection list

FIG. 11 is a diagram illustrating a configuration example of a retransmission request packet.

FIG. 12 is a flowchart of a retransmission request process in a receiving device.

FIG. 13 is a flowchart of a retransmission process in the transmission device.

FIG. 14 is a graph visually representing a request for retransmission of a packet constituting a content.

FIG. 15 is a second flowchart of a retransmission request process in the receiving device.

FIG. 16 is a diagram showing a display example for urging the user to select a retransmission route.

FIG. 17 is a graph showing the number of retransmission requests.

FIG. 18 is a flowchart of a data rate change process in the transmission device.

FIG. 19 is a diagram showing an example of a graph representing the audience rating of content.

FIG. 20 is a flowchart illustrating an example of communication transmitted and received regarding a retransmission request.

FIG. 21 is an image diagram of a data distribution system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 101 transmission device 103 packet generation means 104 broadcast transmission control means 105 broadcast transmission means 106 response transmission means 107 retransmission request reception means 108 retransmission control means 109 packet storage means 110 retransmission request storage means 111 reception status aggregation means 112 charging means 121 broadcast distribution Path 122 two-way communication path 131 receiving device 133 data reconstructing means 134 broadcast receiving control means 135 broadcast receiving means 136 response receiving means 137 retransmission request transmitting means 138 retransmission request controlling means 139 packet storage means 140 retransmission request storage means 141 error detection means 142 data selection means 143 accounting support means

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Eiji Ueda 3-10-18 Kagamiyama, Higashihiroshima City Matsushita Electric Information System Hiroshima Laboratory F-term (reference) 5C063 AB07 AB11 AC01 AC05 CA23 DA01 DA07 DA13 EB07 EB32 EB50 5C064 BA01 BB01 BB05 BC01 BC10 BC18 BC20 BC25 BD02 5K030 GA03 HA08 HB02 HB18 HB21 HC11 JL01 JL08 JT02 LA01 LD07 MA06 MB05

Claims (23)

[Claims] 1. A receiving apparatus for receiving data broadcasted from a transmitting apparatus via a broadcasting path using a broadcast wave as a medium, an error detecting means for detecting an error in the received data, Retransmission request control means for transmitting a retransmission request, which is a request for retransmission of data, through a bidirectional communication path capable of bidirectional data transmission; and A receiving unit for receiving data corresponding to the retransmission request. 2. When the reception of the data and the retransmission request are performed in units of packets constituting the data, a packet corresponding to the retransmission request received from the broadcast distribution path or the bidirectional distribution path is determined to be normal. 2. The receiving apparatus according to claim 1, further comprising: data reconstructing means for reconstructing the data by using the received packet. 3. The apparatus according to claim 1, further comprising: a data selecting unit that selects data for which a retransmission request is made based on a packet having an error and a predetermined threshold value. 3. The receiving device according to claim 2, wherein only the retransmission request is transmitted. 4. The apparatus according to claim 3, wherein said data selection means receives selection of data to be received by a user, and said retransmission request control means transmits a retransmission request only for the data selected by said user. Receiver. 5. The receiving apparatus according to claim 1, wherein the retransmission request control means specifies a retransmission path of the data in the retransmission request. 6. A receiving method for receiving data broadcasted from a transmitting device via a broadcast distribution path using a broadcast wave as a medium, comprising: an error detecting step of detecting an error in the received data; A retransmission request step of transmitting a retransmission request, which is a request for retransmission of data, through a bidirectional communication path capable of bidirectional data transmission; and the retransmission request from the broadcast distribution path or the bidirectional communication path. A receiving step of receiving data corresponding to the request. 7. An error detecting step for detecting an error in the received data by a receiving device that receives data broadcasted from a transmitting device via a broadcast distribution path using a broadcast wave as a medium; A retransmission request step of transmitting a retransmission request, which is a request for retransmission of data, through a bidirectional communication path capable of bidirectional data transmission; and the retransmission request from the broadcast distribution path or the bidirectional communication path. A receiving step of receiving data corresponding to the request. 8. An error detecting step for detecting an error in the received data, wherein the receiving apparatus receives data broadcasted from a transmitting apparatus via a broadcast distribution path using a broadcast wave as a medium. A retransmission request step of transmitting a retransmission request, which is a request for retransmission of data, through a bidirectional communication path capable of bidirectional data transmission; and the retransmission request from the broadcast distribution path or the bidirectional communication path. And a receiving step of receiving data corresponding to the request. 9. A transmitting apparatus for broadcasting data via a broadcasting path using a broadcast wave as a medium, wherein a receiving apparatus from which the data is transmitted receives a retransmission request for retransmitting the data, Retransmission request receiving means for receiving via a bidirectional communication path capable of bidirectional data transmission, retransmission request storage means for storing the retransmission request, and retransmission request stored in the retransmission request storage means Retransmission control means for selecting a transmission path used for retransmission of data corresponding to the retransmission request from the broadcast distribution path or the two-way communication path, and retransmitting the corresponding data via the selected transmission path. A transmission device comprising: 10. The transmission apparatus according to claim 9, wherein said retransmission control means selects said data transmission path based on the number of retransmission requests stored in said retransmission request storage means. 11. The transmitting apparatus according to claim 9, wherein said retransmission control means retransmits data corresponding to a number of retransmission requests equal to or greater than a predetermined threshold value from said broadcast path. 12. The transmitting apparatus according to claim 11, wherein said retransmission request is transmitted in units of packets constituting said data, and said transmission path is selected in units of said packets. 13. The transmitting apparatus according to claim 9, wherein said retransmission control means determines a retransmission order of packets constituting said data based on retransmission waiting time information of a receiving apparatus included in said retransmission request. 14. The transmitting apparatus according to claim 9, wherein said retransmission control means transmits data from said broadcast distribution path or said bidirectional communication path specified by a retransmission request transmitted from said receiving apparatus. 15. The retransmission control means according to claim 9, wherein said retransmission control means dynamically changes transmission efficiency or transmission quality in said broadcast distribution path based on the number of retransmission requests stored in said retransmission request storage means. The transmitting device according to the above. 16. A transmitting apparatus for broadcasting data via a broadcasting channel using a broadcast wave as a medium, wherein the transmitting apparatus transmits unreceivable data that cannot be received to a receiving apparatus to which the data is transmitted. Control means, retransmission request receiving means for receiving a retransmission request from the receiving device, which is a request for retransmission of the unreceivable data, via a bidirectional communication path capable of bidirectional data transmission, A transmission apparatus comprising: a retransmission request storage unit that stores therein; and a reception status totalization unit that totalizes the reception status of the reception device based on the retransmission request stored in the retransmission request storage unit. 17. The transmitting apparatus according to claim 16, wherein the reception status is a rating of each data. 18. A transmitting apparatus for broadcasting data via a broadcasting channel using a broadcast wave as a medium, wherein the transmitting apparatus transmits unreceivable data that cannot be received to a receiving apparatus to which the data is transmitted. Control means, retransmission request receiving means for receiving a retransmission request from the receiving device, which is a request for retransmission of the unreceivable data, via a bidirectional communication path capable of bidirectional data transmission, A transmission apparatus comprising: a retransmission request storage unit for storing; and a charging unit for performing authentication and / or charging of a receiving device that has transmitted the retransmission request based on the retransmission request stored in the retransmission request storage unit. . 19. A transmission method for broadcasting data via a broadcasting channel using a broadcast wave as a medium, wherein a retransmission request, which is a request for retransmission of the data, is received from a receiving device to which the data is to be transmitted. A receiving step of receiving via a bidirectional communication path capable of bidirectional data transmission, based on the retransmission request, a transmission path used for retransmission of data corresponding to the retransmission request, the broadcast distribution path or A transmission method, comprising: a selection step of selecting from the two-way communication path; and a retransmission step of retransmitting data corresponding to the retransmission request via the selected transmission path. 20. A retransmission request, which is a request for retransmission of the data, is transmitted from a receiving device to which the data is to be transmitted to a transmission device that broadcasts the data via a broadcast distribution channel using a broadcast wave as a medium. A receiving step of receiving via a bidirectional communication path capable of bidirectional data transmission, based on the retransmission request, a transmission path used for retransmission of data corresponding to the retransmission request, the broadcast distribution path or A program for executing a selection step of selecting from the bidirectional communication path and a retransmission step of retransmitting data corresponding to the retransmission request via the selected transmission path. 21. A retransmission request, which is a request for retransmission of the data, from a receiving device to which the data is to be transmitted, to a transmission device that broadcasts the data via a broadcast distribution channel using a broadcast wave as a medium. A receiving step of receiving via a bidirectional communication path capable of bidirectional data transmission, based on the retransmission request, a transmission path used for retransmission of data corresponding to the retransmission request, the broadcast distribution path or A computer-readable storage medium storing a program for executing a selection step of selecting from the two-way communication path and a retransmission step of retransmitting data corresponding to the retransmission request via the selected transmission path. 22. A broadcast data distribution method for broadcasting data from a transmitting side via a broadcasting path using broadcast waves as a medium and receiving the broadcasted data at a receiving side. A transmitting step of transmitting a retransmission request, which is a request for retransmission of the data containing the error, via a bidirectional communication path capable of transmitting data in both directions; and Selecting a transmission path used for retransmission of data corresponding to the retransmission request from the broadcast distribution path or the two-way communication path based on the transmission path selected from the data corresponding to the retransmission request. A retransmission step of retransmitting the broadcast data. 23. A receiving apparatus for receiving a plurality of contents included in data broadcasted from a transmitting apparatus via a broadcasting path using a broadcast wave as a medium, wherein an error in a packet constituting the received data is provided. Error detecting means for detecting the content, and excluding the content including the packet containing the error,
A receiving apparatus comprising: a data selection unit that creates a distribution data list including only normally received contents and displays the distribution data list so that the user can select the distribution data list.