JP2010154154A - Broadcast communication system and broadcast communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a broadcast communication system for performing transmission in accordance with the reception state of a receiver when transmitting one piece of information from a transmitter to a plurality of receivers by broadcast communication. <P>SOLUTION: Each broadcast communication client 23 sets a value of a bit corresponding to post-division data received by itself to "1", and a value of a bit corresponding to post-division data not received by itself to "0" concerning the post-division data transmitted from a broadcast communication server 21. When the broadcast communication server 21 receives the reception state information of such bit strings as "11101101", "11001101", and "11000101" from the broadcast communication clients 23-1 to 3, the broadcast communication server 21 obtains a logical product of each bit in each bit string so as to acquire a bit string of "11000101". Then, it is determined that post-division data with sequence numbers "2", "3", "4", "6" are not received by any of the broadcast communication clients 23. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a broadcast communication system that transmits one piece of information from a transmission device to a plurality of reception devices via broadcast communication, and more particularly to a transmission that transmits one piece of information according to a reception situation in the reception device.

A conventional broadcast communication system will be described. As a conventional broadcast communication system, the same data is transmitted m times from the transmission side, and a request for recovery transmission is made when a packet having the same data cannot be normally received once at the reception side. There is.
JP 2000-106559 A

However, the aforementioned broadcast communication system has the following points to be improved. In the above-described broadcast communication system, if a certain receiving side cannot receive a packet, recovery transmission is requested for the packet. Therefore, even when the same packet cannot be received by a plurality of reception sides, recovery transmission is requested from each reception side, so that there is a point to be improved in that the processing load on the transmission side increases.
Therefore, the present invention provides a broadcast communication system that can transmit one piece of information from a transmission device to a plurality of reception devices via broadcast communication according to the reception status of the reception device.

Means for solving the problems in the present invention and the effects of the invention will be described below.
The broadcast communication system according to the present invention is a broadcast communication system in which a transmission apparatus transmits one information to one or more reception apparatuses. The transmission apparatus divides one information into a plurality of pieces of division information. Means, division specifying information adding means for adding division specifying information for specifying the division information to the division information, and broadcast communication means for transmitting the division information to which the division specifying information is added by broadcast communication. The reception apparatus includes: a division information receiving unit that receives the division information; a division identification information extraction unit that extracts the division identification information from the division information; and the division information using the division identification information for the one information. Division information reception status judgment means for judging the reception status of the received information, and having reception status information for each division information indicating whether or not each of the division information has been acquired based on the reception status Reception status report information generating means for generating reception status report information, and reception status report information transmitting means for transmitting the reception status report information by broadcast communication, wherein the transmission device receives the reception status report information Based on the reception status information extracted from the reception status report information acquired from a plurality of reception devices, reception status information extraction means for extracting the reception status information from the reception status report information, reception status report information, A determination unit that determines the reception status of the division information for each of the reception devices; and a retransmission unit that transmits the division information determined that any of the reception devices is not received by broadcast communication.
Thereby, since the division information determined not to be received by any one of the reception devices is retransmitted via broadcast communication, the transmission device does not need to cope with the retransmission of the division information for each reception device. Therefore, the processing burden on the transmission device can be reduced.

In the broadcast communication system according to the present invention, the reception status report information generation means of the receiver uses “0” or “1” for each piece of division information to determine whether or not each piece of the division information has been acquired. The received reception status information is described in a reception status description area included in the reception status report information, and the reception status information extraction unit of the transmission device extracts the reception status information from the reception status description area of the reception status report information. To extract.
Thereby, the receiving device can easily notify its own reception status, and the transmission device can easily determine the reception status of the division information for each of the receiving devices.

In the broadcast communication system according to the present invention, the determination means performs a logical operation on the value of the reception status information acquired from each of the receiving devices for each piece of the division information, thereby determining the reception status for each piece of the division information. to decide.
Thereby, the transmission device can easily determine the reception status of the division information for each of the reception devices.

In the broadcast communication system according to the present invention, the determination means further calculates a total number of “0” or “1” for each piece of the division information, the value of the reception status information acquired from each of the receiving devices, Based on the calculated total number, the division information determined to have a large number of receiving apparatuses that have not been received is preferentially transmitted.
Thereby, division | segmentation information can be efficiently transmitted to a receiver.

In the broadcast communication system according to the present invention, the receiving device further includes reception status report information receiving means for receiving the reception status report information, and reception status information extracting means for extracting the reception status information from the reception status report information. The reception status report information generating means further determines the reception status in the other reception device based on the reception status information of the reception status report information, and acquires the reception status report information in the other reception device. It is assumed that the division information that has not been acquired in the reception status of the user.
Thereby, since the receiving apparatus does not request retransmission for the division information requested to be retransmitted by another receiving apparatus, the transmitting apparatus can reduce the division information to be retransmitted.

In the broadcast communication system according to the present invention, the reception status report information generating means indicates whether or not each of the division information has been acquired by using “0” or “1” for each division information. Status information is described in a reception status description area included in the reception status report information, and the reception status information extraction unit of the receiving apparatus extracts the reception status information from the reception status description area of the reception status report information.
As a result, the receiving apparatus can easily determine the division information for which it does not request retransmission.

In the broadcast communication system according to the present invention, the reception status report information generating means performs a logical operation on the value of the reception status information acquired from the other receiving device and the value of the reception status information of itself. The reception status of the division information is determined.
As a result, the receiving apparatus can easily determine the division information for which it does not request retransmission.

In the broadcast communication system according to the present invention, the receiving device further includes reception status report information receiving means for receiving the reception status report information, and reception status information extracting means for extracting the reception status information from the reception status report information. The other device reception status judgment means for judging the reception status of the division information in the other reception device based on the reception status information extracted from the reception status report information, the division information acquired by itself. And re-sending means for transmitting the division information determined not to be received by any of the receiving devices by broadcast communication.
Thereby, the receiving apparatus can transmit the division information that is received by itself, that is, the division information that is not received by other receiving apparatuses.

In the broadcast communication system according to the present invention, the other apparatus reception status judging means further indicates whether or not each of the division information has been acquired by using “0” or “1” for each division information. Based on the reception status information, the reception status of the division information is determined for another broadcast communication device.
Thereby, the receiving apparatus can easily determine the division information that is received by the receiving apparatus and that is not received by other receiving apparatuses.

In the broadcast communication system according to the present invention, the other device reception status determination means performs a logical operation on the value of the reception status information acquired from the other reception device and the value of the reception status information of itself. The reception status of the division information is determined.
Thereby, the receiving apparatus can easily determine the division information that is received by the receiving apparatus and that is not received by other receiving apparatuses.

The broadcast communication device according to the present invention is a division information receiving means for receiving division information in which one piece of information is divided into a plurality of pieces, and to which division identification information for specifying the division information is added, the division Division specific information extraction means for extracting the division specific information from information, division information reception status determination means for determining the reception status of the division information using the division specific information for the one information, based on the reception status, Reception status report information generating means for generating reception status report information having reception status information for each division information indicating whether or not each of the division information has been acquired, and transmitting the reception status report information by broadcast communication Reception status report information transmission means.
Accordingly, the reception status of the division information of itself can be transmitted to other broadcast communication devices via broadcast communication.

In the broadcast communication apparatus according to the present invention, the reception status report information generating means indicates whether or not each of the division information has been acquired by using “0” or “1” for each division information. State information is described in a reception state description area included in the reception state report information.
Thereby, it is possible to simply represent the reception status of its own division information.

In the broadcast communication apparatus according to the present invention, the broadcast communication apparatus further includes reception status report information receiving means for receiving the reception status report information, and the reception status report information generating means further includes the reception status report information generating means. Based on the reception status information of the reception status report information, the reception status in the other broadcast communication device is determined, and the division information that has not been acquired in the other broadcast communication device, the own reception status It is assumed that
As a result, it is possible to transmit the determined reception status in consideration of the reception status of other communication devices.

In the broadcast communication device according to the present invention, the broadcast communication device further includes the reception status information extracting means for extracting the reception status information from the reception status description area of the reception status report information, The reception status report information generating means includes a reception status report information having the reception status information indicating whether or not each of the division information has been acquired by using “0” or “1” for each division information. Describe in the status description area.
Thereby, it is possible to easily determine the division information that does not request retransmission again.

In the broadcast communication device according to the present invention, the reception status report information generating means includes a value of a reception status description area of the reception status information acquired from another broadcast communication device and a value of the reception status information of itself. Are logically operated to determine the reception status of the division information.
Thereby, it is possible to easily determine the division information that does not request retransmission again.

In the broadcast communication device according to the present invention, the broadcast communication device further includes reception status report information receiving means for receiving the reception status report information, and reception status information for extracting the reception status information from the reception status report information. Based on the reception status information extracted from the reception status report information, extraction means, other device reception status determination means for determining the reception status of the split information for the other broadcast communication device, Re-transmission means for transmitting the division information, which is division information, which is determined not to be received by another broadcast communication device, by broadcast communication.
Thereby, it is possible to transmit the division information which is not received by other broadcast communication devices and which is received by itself.

In the broadcast communication device according to the present invention, the other device reception status determination means further indicates whether each of the division information has been acquired by using “0” or “1” for each division information. Based on the reception status information, the reception status of the division information is determined for another broadcast communication device.
Accordingly, it is possible to easily determine the division information that is not received by other broadcast communication devices and that is received by itself.

In the broadcast communication device according to the present invention, the other device reception status determination means performs a logical operation on the value of the reception status information acquired from the other broadcast communication device and the value of the reception status information of itself. Thus, the reception status of the division information is determined.
Accordingly, it is possible to easily determine the division information that is not received by other broadcast communication devices and that is received by itself.

The broadcast communication device according to the present invention is a reception status report information receiving means for receiving reception status report information; from the reception status report information, one piece of information divided into a plurality of pieces of information in another broadcast communication device; Receiving status information extracting means for extracting receiving status information indicating whether or not each has been acquired for each division information, the receiving status extracted from the receiving status report information acquired from a plurality of the other broadcast communication devices Based on the information, determination means for determining the reception status of the division information for each of the other broadcast communication devices, and the division information determined that any of the other broadcast communication devices is not received Re-transmission means for transmitting by communication.
Thereby, it is possible to easily determine the reception status of the division information for each of the broadcast communication devices.

In the broadcast communication device according to the present invention, the reception status information extracting unit is configured to obtain a piece of divided information obtained by dividing one piece of information into a plurality of pieces in another broadcast communication device from a reception status description area included in the reception status report information. The reception status information is extracted by using “0” or “1” for each piece of division information to determine whether or not each has been acquired.
Thereby, it is possible to easily determine the reception status of the division information for each of the broadcast communication devices.

In the broadcast communication device according to the present invention, the determination means further performs a logical operation on the value of the reception status information acquired from each of the reception devices for each piece of the division information, so that the reception for each piece of the division information is performed. Determine the situation.
Thereby, the transmission device can easily determine the reception status of the division information for each of the reception devices.

In the broadcast communication apparatus according to the present invention, the determination means further adds the value of the reception status information acquired from each of the other broadcast communication apparatuses to a total number of “0” or “1” for each piece of the divided information. And the division information determined to be large in number of the broadcast communication devices not received based on the calculated total number is preferentially transmitted.
Thereby, division | segmentation information can be efficiently transmitted to a receiver.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Function of First Broadcast Communication System 1 The function of the broadcast communication system 1 according to the present embodiment will be described with reference to the functional block diagram shown in FIG. The broadcast communication system 1 includes a broadcast communication server 21 and a broadcast communication client 23. In the broadcast communication system 1, the broadcast communication server 21 transmits one piece of information to a plurality of broadcast communication clients 23.
The broadcast server 21 includes an information division unit m211, a division specific information addition unit m212, a broadcast communication unit m213, a reception status report information reception unit m214, a reception status information extraction unit m215, a determination unit m216, and a retransmission unit m217. is doing.
The broadcast communication client 23 includes a division information receiving unit m231, a division specific information extracting unit m232, a division information reception status determination unit m233, a reception status report information generation unit m234, and a reception status report information transmission unit m235.

The information dividing unit m211 divides one piece of information into a plurality of pieces of divided information. The division specifying information adding unit m212 adds division specifying information for specifying the division information to the division information. The broadcast communication means m213 transmits the division information to which the division specific information is added by broadcast communication.
The division information receiving unit m231 receives the division information. The division specific information extraction unit m232 extracts the division specific information from the division information. The division information reception status determination unit m233 determines the reception status of the division information (that is, whether or not the division information has been acquired) using the division identification information for the one information. The reception status report information generation unit m234 generates reception status report information having reception status information representing the reception status for each piece of division information based on the reception status. That is, the reception status report information generation unit m234 indicates whether or not each of the division information has been acquired by using the reception status information indicating “0” or “1” for each division information. It is described in the reception status description area. The reception status report information transmitting means m235 transmits the reception status report information by broadcast communication.

The reception status report information receiving means m214 receives the reception status report information. The reception status information extraction unit m215 extracts the reception status information from the reception status description area of the reception status report information.
The determination unit m216 determines the reception status of the division information for each of the broadcast clients 23 based on the reception status information extracted from the reception status report information acquired from the plurality of broadcast clients 23. . That is, the determination unit m216 determines the reception status for each piece of the divided information by performing a logical operation on the value of the reception state information acquired from each of the broadcast clients 23 for each piece of the divided information. Further, the determination unit m216 calculates the total number of “0” or “1” for each piece of the division information from the value of the reception status information acquired from each broadcast client 23, and based on the calculated total number, Ranking is performed so as to preferentially transmit the division information determined that there are many broadcast communication clients 23 that have not been received.

The retransmitting means m217 transmits the division information determined to be not received by any of the broadcast communication clients 23 by broadcast communication.
Thereby, since the division information determined not to be received by any one of the reception devices is retransmitted via broadcast communication, the transmission device does not need to cope with the retransmission of the division information for each reception device. Therefore, the processing burden on the transmission device can be reduced. In addition, when the receiving apparatus notifies the reception status of itself, the transmitting apparatus can easily determine the reception status of the division information for each of the receiving apparatuses comprehensively. Furthermore, the division information can be efficiently transmitted to the receiving device.

Second Configuration of Broadcast Communication System 1 Network Configuration of Broadcast Communication System 1 The network configuration of the broadcast communication system 1 is shown in FIG. The broadcast communication system 1 includes a broadcast communication server 21 and a broadcast communication client 23. The broadcast communication server 21 and the broadcast communication client 23 can transmit and receive by broadcast communication via a network using wireless communication.
The broadcast client 23 has a plurality of broadcast clients 23-1, 23-2, 23-3,. In the following, the description of the broadcast client 23-n is intended for individual broadcast clients, and the description of the broadcast client 23 is broadcast without distinguishing between individual broadcast clients. It means the whole client. The broadcast communication server 21 and the broadcast communication client 23 will be described below.

2. Hardware Configuration of Broadcast Communication Server 21 The hardware configuration of the broadcast communication server 21 is illustrated in FIG. The broadcast communication server 21 includes a CPU 211, a memory 212, a hard disk 213, a keyboard 214, a mouse 215, a display 216, an optical drive 217, and a communication circuit 218.
The CPU 211 performs processing based on other applications such as an operating system (OS) and a broadcast server program recorded on the hard disk 213. The memory 212 provides a work area for the CPU 211. The hard disk 213 records and holds other applications such as an operating system (OS) and a broadcast server program.
The keyboard 214 and the mouse 215 accept external commands. The display 216 displays an image such as a user interface. The optical drive 217 reads the broadcast server program from the optical medium 210 in which the broadcast server program is recorded, reads other application programs from other optical media, and so on. Read the data. The communication circuit 218 includes a communication circuit connected to a network, and transmits / receives data to / from an external communication device based on broadcast communication.

3. Hardware Configuration of Broadcast Client 23 The hardware configuration of the broadcast client 23 is illustrated in FIG. The broadcast communication client 23 includes a CPU 231, a memory 232, a hard disk 233, a keyboard 234, a mouse 235, a display 236, an optical drive 237, and a communication circuit 238.
The CPU 231 performs processing based on other applications such as an operating system (OS) and a broadcast client program recorded on the hard disk 233. The memory 232 provides a work area for the CPU 231. The hard disk 233 records and holds other applications such as an operating system (OS) and a broadcast client program.
The keyboard 234 and the mouse 235 accept external commands. The display 236 displays an image such as a user interface. The optical drive 237 reads the broadcast client program from the optical medium 230 on which the broadcast client program is recorded, reads other application programs from other optical media, and so on. Read the data. The communication circuit 238 includes a communication circuit connected to a network, and transmits / receives data based on broadcast communication with an external communication device.

Third Operation of Broadcast Communication System 1 The operation of the broadcast communication system 1 will be described with reference to the flowchart shown in FIG. The CPU 211 of the broadcast communication server 21 executes a dividing process for dividing predetermined data to be broadcasted into a plurality of packets (S501). The division process will be described later.
The CPU 211 transmits the packet generated by the dividing process by broadcast communication (S503). The CPU 211 uses UDP (User Datagram Protocol) for broadcast communication.
When the CPU 231 of the broadcast communication client 23 receives a packet transmitted by the broadcast communication (S511), the CPU 231 executes a division specific information extraction process (S513). The division specific information extraction process will be described later.
When the CPU 231 determines that the predetermined time has elapsed (S515), it executes reception status report information generation processing for generating reception status report information (S517). The reception status report information generation process will be described later.
The CPU 231 transmits the reception status report information generated by the reception status report information generation processing by broadcast communication (S519). The CPU 231 uses UDP (User Datagram Protocol) for broadcast communication.

When receiving the reception status report information (S505), the CPU 211 executes a client reception status determination process (S507) for determining the reception status of the packet in each of the broadcast clients 23-1, 23-2,. The client reception status determination process will be described later. Based on the result of the client reception status determination process, the CPU 211 retransmits a packet not received by any broadcast communication client 23 by broadcast communication (S509).
Hereinafter, the division process (S501), the division specific information extraction process (S513), the reception status report information generation process (S517), and the client reception status determination process (S507) will be described.

1. Division Processing Division processing executed by the CPU 211 of the broadcast communication server 21 will be described with reference to the flowchart shown in FIG. The CPU 211 divides predetermined data to be divided (hereinafter, divided original data) into a predetermined size, and generates divided data (S601). The size to be divided is set in advance. Then, the CPU 211 adds a division header to each of the divided data (S603).
The data structure of the divided header will be described with reference to FIG. 7A. The divided header H601 has a data number description area C601, an offset description area C603, a data size description area C605, a sequence number description area C607, and a total packet number description area C609.
The data number description area C601 is an area for describing a number for specifying the division source data. The offset description area C603 is an area for describing the position of divided data with respect to divided original data. The data size description area C605 is an area for describing the size of the divided data. The sequence number description area C607 is an area for describing a number for specifying the divided data. The total packet number description area C609 is an area for describing the total number of packets when the divided data is transmitted as a packet, that is, the total number of divided data.

For example, as shown in FIG. 7B, when dividing source data D1 whose data number is “1” is divided as divided data having a size of 100 bytes, the dividing source data is four pieces of divided data D11 to D14. It is divided into.
At this time, as shown in FIG. 7C, the following values are described in the divided header H601 of the divided data D11. In the data number description area C601, the data number “1” of the division source data is described. In the offset description area C603, “0” is described because the post-division data D11 corresponds to the head of the division source data D1, that is, the data of 100 bytes from the 0th byte of the division source data. In the data size description area C605, “100” is described because the data size of the divided data D11 is 100 bytes. In the sequence number description area C607, “0” is described because the post-division data D11 is the first data with respect to the division source data D1. Note that “0” is the first value for the sequence number. In the total packet number description area C609, “3” is described as the number of the divided data D11 to D14. The number of divided data is described as “0” when the number of divided data is one. For the other divided data D12, the data number description area, the size description area, and the total packet number description area are the same as those of D11, but the first byte “100” of the second divided data is described in the offset description area. In the sequence number description area, “1” indicating the second data is described. D13 and D14 are also as described in FIG. 7C.
Returning to FIG. 6, the CPU 211 adds a UDP header to the divided data to which the divided header H601 is added (S605). Further, the CPU 211 adds an IP header to the divided data to which the UDP header is added (S607).
The CPU 211 generates a packet to be transmitted to the broadcast communication client 23 through the processes of steps S601 to S607. A data structure of a packet finally generated by the CPU 211 is shown in FIG.

2. Division Specific Information Extraction Processing Division specific information extraction processing executed by the CPU 231 of the broadcast communication client 23 will be described with reference to the flowchart shown in FIG. The CPU 231 extracts the divided header H601 from the received packet (S901). The CPU 231 acquires values of the data number description area C601, the offset description area C603, the data size description area C605, the sequence number description area C607, and the total packet number description area C609 from the extracted divided header H601 (S903). It is temporarily stored in the memory 232 as specific information (S905). The divided data is also temporarily stored in the memory 232.

3. Reception Status Report Information Generation Processing Reception status report information generation processing executed by the CPU 231 of the broadcast communication client 23 will be described using the flowchart shown in FIG. The CPU 231 extracts the value of the sequence number description area C603 and the value of the total packet number description area C609 for packets having the same value in the data number description area C601 from the division specific information temporarily stored in the memory 232 (S909). Then, the reception status of the divided data, that is, which sequence number of the divided data is not received is determined (S911).
The CPU 231 generates reception status information indicating whether or not all the divided data generated from the divided original data are received within a predetermined time (S913). Then, the CPU 231 generates reception status report information in which the generated reception status information is described in the reception status information description area (S915).

Here, the reception status information and the reception status report information will be described with reference to FIG. As shown in FIG. 10A, the broadcast server 21 generates divided data obtained by dividing the divided original data into eight, and transmits the packet generated by adding the divided header, UDP header, and IP header to the broadcast client. Assume that broadcast communications are made to 23-1, 23-2, and 23-3. Note that the sequence number of the divided data starts from “0”.
As shown in FIG. 10B, the broadcast client 23-1 cannot receive the divided data of the sequence numbers “3” and “6”, and the broadcast client 23-2 receives the sequence numbers “2” and “3”. , “6” cannot be received, and the broadcast communication client 23-3 cannot receive the divided data of sequence numbers “2”, “3”, “4”, and “6”.
In this case, the broadcast clients 23-1, 23-2, and 23-3 each generate “8” -bit reception status information that is the total number of divided data that is the value of the total number of packets. Each bit of the generated reception status information corresponds to the divided data whose leading bit is sequence number “0”, and is sequentially carried up. Each broadcast client 23 describes the bit value corresponding to the divided data received by itself as “1” and the bit value corresponding to the divided data that could not be received as “0”.

That is, the broadcast communication client 23-1 in FIG. 10B generates reception status information having a bit notation “11101101” as illustrated in FIG. 10C. The same applies to other broadcast clients 23.
Here, the data structure of the reception status report information will be described with reference to FIG. The reception status report information has a data number description area C1101 and a reception status description area C1103. In the data number description area C1101, the data number of the division source data is described, and in the reception status description area C1103, the generated reception status information expressed in bits is described.
Returning to FIG. 9-2, the CPU 231 adds a UDP header to the generated reception status report information (S917), and further adds an IP header (S919).

3. Client Reception Status Judgment Processing Client reception status judgment processing executed by the CPU 211 of the broadcast communication server 21 will be described with reference to the flowchart shown in FIG. The CPU 211 extracts the value described in the data number description area C1101 and the reception status information described in the reception status description area C1103 from the received reception status report information (S1201), and temporarily stores them in the memory 212. The CPU 211 repeats the process of step S1201 until a predetermined time has elapsed (S1203).
When the CPU 211 determines that the predetermined time has elapsed, the CPU 211 performs a logical operation for each bit string on the reception status information having the value of the same data number description area C1101 (S1205). Further, the CPU 211 performs addition operation for each bit string with respect to the reception status information having the value of the same data number description area C1101 (S1207).
The CPU 211 retransmits the divided data that has not been received by any broadcast communication client 23, that is, the divided data corresponding to the sequence number whose bit string value is “0” as a result of the logical operation. The order is determined (S1209). As for the re-transmission order of the divided data to be re-transmitted, priority is given to the one having a smaller value of the corresponding addition operation.

For example, as shown in FIG. 10C, the reception status information “11101101” from the broadcast communication client 23-1, the reception status information “11001101” from the broadcast communication client 23-2, and the broadcast communication client 23-3. It is assumed that the reception status information of “11000101” is received from each. In this case, the broadcast communication server 21 executes a logical operation that performs a logical product of “11101101”, “11001101”, and “11000101” for each bit string.
As a result of the logical operation, the bit notation of “11000101” is obtained as shown in FIG. 13A. From the result of the logical operation, the CPU 211 indicates that any broadcast communication client 23 has received the divided data of the sequence number “2”, the sequence number “3”, the sequence number “4”, and the sequence number “6”. Judge that there is no. As described above, the CPU 211 can easily determine post-division data that has not been received by any one of the broadcast clients 23 only by performing a logical operation on the reception status information expressed in bits.

As a result of the addition operation, as shown in FIG. 13B, the sequence number “2”, the sequence number “3”, the sequence number “4”, and the sequence that are determined not to be received by any broadcast communication client 23 For the data after division of the number “6”, addition values “1”, “0”, “2”, and “0” are obtained, respectively. From the result of the addition operation, the CPU 211 gives the highest priority to the order of retransmission of the divided data with the sequence number “3” and the sequence number “6” having the addition value “0”, and the sequence having the addition value “1”. It is determined that the order of retransmission of data after division of number “2” is next, and the order of retransmission of data after division of sequence number “4” having an addition value of “2” is next. In this way, the CPU 211 can easily determine in which order the divided data that has not been received by any one of the broadcast communication clients 23 should be retransmitted only by adding the reception status information expressed in bits. This makes it possible to perform efficient data retransmission.

In the above-described first embodiment, the divided data (data not yet arrived divided) that has not been received by the broadcast communication client is received and retransmitted from the broadcast server by the broadcast client. In the example, if it is determined that there is a broadcast client that requests retransmission for the same unarrived divided data, further retransmission can be expected because the undivided divided data can be expected to be retransmitted. Do not request.
In the following description, the same components and processes as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

Functional Block of First Broadcast Communication System The function of the broadcast communication system 3 according to the present embodiment will be described with reference to the functional block diagram shown in FIG. The broadcast communication system 3 includes a broadcast communication server 21 and a broadcast communication client 43.
The broadcast communication client 43 further includes reception status report information receiving means m431 and reception status information extracting means m433 in addition to the means described in the broadcast communication client 23 shown in FIG. The reception status report information receiving means m431 receives reception status report information from other broadcast communication clients (reception devices). The reception status information extraction unit m433 extracts reception status information from the reception status report information.

In addition, the reception status report information generation unit m234 further determines the reception status in the other reception device based on the reception status information of the reception status report information, and determines that the reception status report information generation unit m234 has not acquired in the other reception device. It is assumed that the information is acquired in its own reception status. The reception status report information generation unit m234 indicates the reception status information using “0” or “1” for each division information as to whether or not the own apparatus has acquired each piece of the division information. Describe in the reception status description area of report information. The reception status report information generation unit m234 determines the reception status of the division information by performing a logical operation on the value of the reception status information acquired from the other receiving device and the value of the reception status information of itself. However, it is assumed that the division information that another receiving apparatus has already requested to retransmit as having not been received has been received.
Thereby, since the receiving apparatus does not request retransmission for the division information requested to be retransmitted by another receiving apparatus, the transmitting apparatus can reduce the division information to be retransmitted. In addition, the receiving apparatus can reduce the processing load for which it requests retransmission.

Second broadcast communication system 3 configuration,
1. Network Configuration of Broadcast Communication System 3 A network configuration of the broadcast communication system 3 according to the present embodiment will be described with reference to FIG. The broadcast communication system 3 includes a broadcast communication server 21 and a broadcast communication client 43. The broadcast communication server 21 and the broadcast communication client 43 can transmit and receive data by broadcast communication via a network using wireless communication.
Note that the notation regarding the broadcast communication client is the same as that in the first embodiment.
2. Hardware configuration of broadcast communication client The hardware configuration of the broadcast communication client 43 is the same as that of the first embodiment. Therefore, detailed description is omitted.

Third Operation of Broadcast Client 43 The operation of the broadcast client 43 will be described with reference to the flowchart shown in FIG. When the CPU 431 of the broadcast communication client 43 receives the reception status report information transmitted from the other broadcast communication client 43 (S1501), the CPU 431 temporarily stores the received reception status report information in the memory 432. Then, the CPU 431 determines whether or not a predetermined time has elapsed (S515). Note that the CPU 431 executes the processes of steps S1501 and S1503 in parallel with the processes of steps S511 and S513.
When the CPU 431 determines that the predetermined time has elapsed, the CPU 431 executes reception status report information generation processing (S1505).
Hereinafter, reception status report information generation processing (S1505) will be described.

2. Reception Status Report Information Generation Processing Reception status report information generation processing executed by the CPU 431 of the broadcast communication client 43 will be described using the flowchart shown in FIG. The CPU 431 acquires the reception status information from the reception status description area C1001 of the received reception status report information (S1601). The CPU 431 acquires the reception status information expressed in its own bit that is temporarily stored in the memory 432 (S1603).
Then, the CPU 431 compares the reception status information extracted in step S1601 with its own reception status information acquired in step S1603 (S1605). For comparison, a negative is calculated for the bit notation of the reception status information acquired in step S1601. As a result, it is possible to identify the divided data not received by the other broadcast client 43, that is, the sequence number of the divided data that can be expected to be retransmitted by the broadcast server 21. Then, the logical sum of the bit notation and the bit notation of the reception status information acquired in step S1603 is calculated. As a result, it is possible to request the broadcast server 21 to retransmit only the divided data that is not received by itself and that cannot be expected to be retransmitted by other broadcast clients 43.

The CPU 431 again generates reception status information indicating whether or not all the divided data generated from the divided original data are received within the predetermined time, or whether or not there is a possibility of receiving in the future. (S1607).
For example, in FIG. 18, the broadcast communication client 43-1 transmits the reception status information in the bit notation “11101101” via the broadcast communication, and the broadcast communication client 43-2 receives the information. Consider a case where the reception status information of the broadcast communication client 43-2 is in a bit notation of “11001101”. In this case, when the broadcast client 43-2 compares the received bit notation “11101101” with the bit notation “11001101” of its own reception status information, first, as shown in FIG. The negation of the bit notation of the reception status report by the communication client 43-1 is calculated, and the bit notation consisting of “00010010” is obtained. Then, the broadcast client 43-1 calculates the logical sum of the obtained bit notation “00010010” and the bit notation “11001101” of its reception status information, and obtains the bit notation “11011111”. As a result, the broadcast communication client 43-2 has not received it, and the broadcast communication client 43-1 cannot expect retransmission, so the sequence number “2” which is not likely to be received in the future. Reception status information is generated as post-division data that cannot be received only for the post-division data. Similarly, the reception status information of the broadcast communication client 43-3 is “11000101”, but since the reception status information from the broadcast communication client 43-1 is received, the divided data “2” and “4” "Only reception status information" is generated. When the reception status information of the broadcast communication client 43-2 is received, the post-division data not received is only “4”.

In the above-described first embodiment, the divided data (data not yet arrived divided) that has not been received by the broadcast communication client is received and retransmitted from the broadcast server by the broadcast client. In the example, another broadcast client that has already received the unsplit data has retransmitted.
In the following description, the same components and processes as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

First Functional Block Diagram Functions of the broadcast communication system 5 according to the present embodiment will be described with reference to a functional block diagram shown in FIG. The broadcast communication system 5 includes a broadcast communication server 21 and a broadcast communication client 63.
In addition to the means included in the broadcast client 23 shown in FIG. 1, the broadcast client 63 further includes a reception status report information receiving means m631, a reception status information extracting means m633, another device reception status judging means m635, and Retransmission means m637 is provided.
The reception status report information receiving means m631 receives reception status report information from other broadcast communication clients (reception devices). The reception status information extraction unit m633 extracts reception status information from the reception status report information.

The other device reception status determination unit m635 determines the reception status of the division information in another reception device based on the reception status information extracted from the reception status report information. In other words, the other apparatus reception status determination unit m635 uses the value “0” or “1” for each division information to indicate whether or not each of the division information has been acquired. The reception status of the division information is determined for the broadcast communication device. Further, the other device reception status determination unit m635 performs the logical operation on the value of the reception status information acquired from the other reception device and the value of the reception status information of itself, thereby obtaining the above-mentioned information. The division information that is determined to be not received by any of the receiving devices is specified.
The retransmitting means m637 transmits the division information that is acquired by the retransmission unit m637 and that is determined not to be received by any of the receiving apparatuses by broadcast communication.
Accordingly, the receiving device can easily determine the division information that is received by the receiving device and is not received by other receiving devices, and does not rely on the broadcast server. The division information that is not received by the receiving apparatus and that is received by itself can be transmitted.

Second Configuration of Broadcast Communication System 1 Network Configuration of Broadcast Communication System 5 A network configuration of the broadcast communication system 5 according to the present embodiment will be described with reference to FIG. The broadcast communication system 5 includes a broadcast communication server 21 and a broadcast communication client 63. The broadcast communication server 21 and the broadcast communication client 63 can transmit and receive data by broadcast communication via a network. Note that the notation regarding the broadcast communication client is the same as that in the first embodiment.
2. Hardware configuration of the broadcast communication client 63 The hardware configuration of the broadcast communication client 63 is the same as that of the first embodiment. Therefore, detailed description is omitted.

Third Operation of Broadcast Client 63 The operation of the broadcast client 63 will be described with reference to the flowchart shown in FIG. The broadcast communication client 63 executes the following processing in parallel with the processing of the broadcast communication client 23 shown in FIG. When receiving the reception status report information transmitted from another broadcast client 63 (S2101), the CPU 631 of the broadcast client 63 executes another client reception status determination process (S2103). Will be described later.
The CPU 431 transmits the packet generated by the other client reception status determination process to the other broadcast communication client 63 via the broadcast communication (S2105).
The other client reception status determination process (S2103) will be described below.

1. Other Client Reception Status Judgment Processing The other client reception status judgment processing executed by the CPU 631 of the broadcast communication client 63 will be described with reference to the flowchart shown in FIG. When the CPU 631 extracts the reception status information from the reception status description area C1001 of the reception status report information received in step S1601, the CPU 631 compares the extracted reception status information with its own reception status information generated in step S913 (S2201).
In the comparison, first, a negative with respect to the bit notation of the reception status information acquired in step S1601 is calculated. Thereby, the sequence number of the data after the division | segmentation which the other broadcast communication client 43 has not received can be specified. Then, the logical product of the negative bit notation and the bit notation of the reception status information generated in step S913 is calculated. As a result, it is possible to specify post-division data that is received by itself and that is not received by the other broadcast client 43 (S2203).

For example, in FIG. 24, the broadcast communication client 63-2 transmits the reception status information in the bit notation of “11001101” via the broadcast communication, and the broadcast communication client 63-1 receives the broadcast status information at this time. Consider a case where the reception status information of the information communication client 63-1 is in the bit notation of “11101101”. In this case, as shown in FIG. 25, when the broadcast client 63-1 compares the received bit notation “11001101” with the bit notation “11101101” of its reception status information, first, the received broadcast notation The negation of the bit notation of the reception status report by the communication client 63-2 is calculated, and the bit notation consisting of “00110010” is obtained. Then, the broadcast client 63-1 calculates the logical product of the obtained bit notation “00110010” and the bit notation “11101101” of its reception status information, and obtains the bit notation “00100000”. Thus, the broadcast communication client 63-1 can identify the post-split data of the sequence number “2” received by itself and not received by the broadcast communication client 63-2. The broadcast communication client 63-1 retransmits the identified divided data to the broadcast communication client 63-2 via broadcast communication.

[Other Examples]
(1) Broadcast communication In the first embodiment, the broadcast communication is performed using UDP. However, the communication protocol is not limited to the illustrated example as long as the communication protocol can perform the broadcast communication.
(2) Reception status report information generation processing In the above-described second embodiment, in the reception status report information generation processing performed by the broadcast communication client 43, the reception status information received from other broadcast communication clients 43 is negated, Further, by taking a logical sum with its own reception status information, it is determined that the data has not been received by itself and the divided data that cannot be expected to be retransmitted by other broadcast communication clients 43. However, the present invention is not limited to the illustrated example as long as it is not received by itself and can determine the divided data that cannot be expected to be retransmitted by other broadcast communication clients 43.

(3) Other Device Reception Status Judgment Process In the above-described third embodiment, in the other device reception status judgment process performed by the broadcast communication client 63, a negative is given to the reception status information received from the other broadcast communication client 43, and Further, by taking a logical product with its own reception status information, it identifies the post-divided data that it has received and that other broadcast clients 43 have not received. However, as long as it is possible to specify post-division data that is received by itself and that is not received by other broadcast clients 43 by performing a logical product with its own reception status information, It is not limited to things.

(4) Broadcast server and broadcast client In the first to third embodiments, the configurations of the broadcast server and the broadcast client are shown in FIGS. 3 and 4. It is not limited to the example as long as the function is realized. For example, the predetermined processing may be realized in cooperation with the operating system.
Moreover, you may make it implement | achieve as an auxiliary | assistant apparatus with respect to a computer. For example, the auxiliary device may be constituted by a CPU, a memory, and a communication circuit, and may be a single product or a built-in product whose main function is broadcast communication.

(5) Network In the above-described first embodiment, the wireless network is exemplified as the network. However, the network is not limited to the illustrated example as long as the broadcast communication can be performed. For example, broadcast communication may be performed via a network using wired communication.

The present invention can be used in a broadcast communication system in which one data is divided into a plurality of packets and transmitted.

1 is a functional block diagram of a broadcast communication system 1 according to the present invention. 1 is a diagram showing a network configuration of a broadcast communication system 1. FIG. 2 is a diagram illustrating a hardware configuration of a broadcast communication server 21. FIG. 2 is a diagram illustrating a hardware configuration of a broadcast communication client 23. FIG. 3 is a flowchart showing the operation of the broadcast communication system 1; It is a flowchart which shows a division | segmentation process. It is a figure which shows a data structure. It is a figure which shows a data structure. It is a flowchart which shows a division | segmentation specific information extraction process. It is a flowchart which shows a reception status report information generation process. It is a figure for demonstrating reception status information and reception status report information. It is a figure which shows a data structure. It is a flowchart which shows a client reception condition judgment process. It is a figure which shows the result of a logical operation. It is a functional block diagram of the broadcast communication system 3 which concerns on this invention. 1 is a diagram showing a network configuration of a broadcast communication system 3. FIG. 4 is a flowchart showing the operation of the broadcast communication client 43. It is a flowchart which shows a reception status report information generation process. It is a figure for demonstrating reception status information and reception status report information. It is a figure which shows a data structure. It is a functional block diagram of the broadcast communication system 3 which concerns on this invention. 1 is a diagram showing a network configuration of a broadcast communication system 5. FIG. 6 is a flowchart showing the operation of the broadcast communication client 63. It is a flowchart which shows a reception status report information generation process. It is a figure for demonstrating reception status information and reception status report information. It is a figure which shows a data structure.

Explanation of symbols

1, 3, 5 ... Broadcast communication system 21, 41, 61 ... Broadcast communication server 23, 43, 63 ... Broadcast communication client

Claims (22)

In a broadcast communication system in which a transmitter transmits one piece of information to one or more receivers,
The transmitter is
Information dividing means for dividing one piece of information into a plurality of pieces of divided information;
Division identification information adding means for adding division identification information for identifying the division information to the division information;
Broadcast communication means for transmitting the division information to which the division specific information is added by broadcast communication;
Have
The receiving device is:
Division information receiving means for receiving the division information;
Division specific information extracting means for extracting the division specific information from the division information;
Division information reception status determination means for determining the reception status of the division information using the division identification information for the one information;
Based on the reception status, reception status report information generating means for generating reception status report information having reception status information for each division information indicating whether or not each of the division information has been acquired,
Reception status report information transmitting means for transmitting the reception status report information by broadcast communication;
Have
The transmitter is
Reception status report information receiving means for receiving the reception status report information;
Reception status information extracting means for extracting the reception status information from the reception status report information;
Determining means for determining the reception status of the division information for each of the reception devices based on the reception status information extracted from the reception status report information acquired from a plurality of the reception devices;
Re-transmission means for transmitting the division information determined not to be received by any of the receiving devices by broadcast communication;
Having
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 1,
The reception status report information generating means of the receiving device,
Describe in the reception status description area of the reception status report information the reception status information indicating whether or not each of the division information has been acquired by using “0” or “1” for each division information,
The reception status information extraction unit of the transmission device includes:
Extracting the reception status information from the reception status description area of the reception status report information;
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 2,
The determination means includes
Determining the reception status for each of the division information by performing a logical operation on the value of the reception status information acquired from each of the reception devices for each of the division information;
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 2 or claim 3,
The determination means further includes:
When the total number of “0” or “1” is calculated for each piece of division information, the value of the reception status information acquired from each receiving device, and when there are many receiving devices that are not receiving based on the calculated total number Preferentially transmitting the determined division information;
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 1,
The receiving device further includes:
Reception status report information receiving means for receiving the reception status report information;
Reception status information extracting means for extracting the reception status information from the reception status report information;
Have
The reception status report information generating means further includes:
Based on the reception status information of the reception status report information, the reception status in the other receiving device is determined, and the division information not acquired in the other receiving device is acquired in the reception status of itself. And
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 5,
The reception status report information generating means includes
Describe in the reception status description area of the reception status report information the reception status information indicating whether or not each of the division information has been acquired by using “0” or “1” for each division information,
The reception status information extracting means of the receiving device is:
Extracting the reception status information from the reception status description area of the reception status report information;
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 6,
The reception status report information generating means includes
Determining the reception status of the division information by performing a logical operation on the value of the reception status information acquired from the other receiving device and the value of the reception status information of itself;
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 1,
The receiving device further includes:
Reception status report information receiving means for receiving the reception status report information;
Reception status information extracting means for extracting the reception status information from the reception status report information;
Based on the reception status information extracted from the reception status report information, other device reception status determination means for determining the reception status of the division information in the other reception devices;
Re-transmission means for transmitting the division information that has been acquired by itself, and that has been determined that any of the receiving devices has not received the broadcast by broadcast communication;
Having
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 8,
The other apparatus reception status judging means further includes:
Based on the reception status information indicating whether or not each piece of the division information has been acquired by using “0” or “1” for each piece of the division information, the reception of the division information for the other broadcast communication devices. Judging the situation,
A broadcast communication system characterized by the above. In the broadcast communication system according to claim 9,
The other apparatus reception status determination means includes
Determining the reception status of the division information by performing a logical operation on the value of the reception status information acquired from the other receiving device and the value of the reception status information of itself;
A broadcast communication system characterized by the above. Division information receiving means for receiving division information in which one piece of information is division information divided into a plurality of pieces and to which division identification information for identifying the division information is added;
Division specific information extracting means for extracting the division specific information from the division information;
Division information reception status determination means for determining the reception status of the division information using the division identification information for the one information;
Based on the reception status, reception status report information generating means for generating reception status report information having reception status information for each division information indicating whether or not each of the division information has been acquired,
Reception status report information transmitting means for transmitting the reception status report information by broadcast communication;
Broadcast communication device having In the broadcast communication device according to claim 11,
The reception status report information generating means includes
Describe in the reception status description area of the reception status report information the reception status information indicating whether or not each of the division information has been acquired using “0” or “1” for each division information;
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 11,
The broadcast communication device further includes:
Reception status report information receiving means for receiving the reception status report information;
Have
The reception status report information generating means further includes:
Based on the reception status information of the reception status report information, the reception status in the other broadcast communication device is determined, and the division information that has not been acquired in the other broadcast communication device is received by the receiver itself. That it was acquired in the situation,
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 13,
The broadcast communication device further includes:
The reception status information extracting means for extracting the reception status information from the reception status description area of the reception status report information;
Have
The reception status report information generating means includes
Describe in the reception status description area of the reception status report information the reception status information indicating whether or not each of the division information has been acquired using “0” or “1” for each division information;
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 14,
The reception status report information generating means includes
Judging the reception status of the division information by performing a logical operation on the value of the reception status description area of the reception status information acquired from another broadcast communication device and the value of the reception status information of itself. ,
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 11,
The broadcast communication device further includes:
Reception status report information receiving means for receiving the reception status report information;
Reception status information extracting means for extracting the reception status information from the reception status report information;
Based on the reception status information extracted from the reception status report information, other device reception status determination means for determining the reception status of the split information for the other broadcast communication device,
Retransmission means for transmitting the division information that has been acquired by itself and that is determined not to be received by the other broadcast communication device by broadcast communication;
Having
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 16,
The other apparatus reception status judging means further includes:
Based on the reception status information indicating whether or not each piece of the division information has been acquired by using “0” or “1” for each piece of the division information, the reception of the division information for the other broadcast communication devices. Judging the situation,
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 17,
The other apparatus reception status determination means includes
Determining the reception status of the division information by performing a logical operation on the value of the reception status information acquired from the other broadcast communication device and the value of the reception status information of itself.
Broadcast communication device characterized by the above. Reception status report information receiving means for receiving reception status report information,
Reception status information that extracts, from the reception status report information, reception status information that indicates whether each piece of division information obtained by dividing one piece of information into other broadcast communication devices is obtained for each division information. Extraction means,
Determining means for determining the reception status of the division information for each of the other broadcast communication devices based on the reception status information extracted from the reception status report information acquired from a plurality of the other broadcast communication devices;
Re-transmission means for transmitting the division information determined by any other broadcast communication device not received by broadcast communication;
Broadcast communication device having In the broadcast communication device according to claim 19,
The reception status information extracting means includes
Whether or not each piece of divided information obtained by dividing one piece of information into a plurality of pieces of information in another broadcast communication device is acquired from the reception state description area included in the reception state report information for each piece of division information. Extracting the reception status information represented by “1”,
Broadcast communication device characterized by the above. In the broadcast communication device according to claim 20,
The determination means further includes:
Determining the reception status for each of the division information by performing a logical operation on the value of the reception status information acquired from each of the reception devices for each of the division information;
Broadcast communication device characterized by the above. In either of the broadcast communication devices according to claim 20 or claim 21,
The determination means further includes:
The total number of “0” or “1” is calculated for each piece of the division information from the value of the reception status information acquired from each of the other broadcast communication devices, and the same number not received based on the calculated total number. Preferentially transmitting the division information determined to have many information communication devices;
Broadcast communication device characterized by the above.