JP2012089961A - Information transfer system - Google Patents

Abstract

An information transfer system capable of stably transferring a large amount of information at high speed regardless of the presence or absence of importance.
A transmission control means 13 receives image information acquired by an image acquisition means 11 and encoded by an encoding means 12, and divides the image information into a plurality of packets. Furthermore, the transmission control means 13 inserts the packets in order from the last packet between the packets when the packets are arranged from the top packet so that all the packets can be transmitted twice, and arranges the packets. The packet is distributed to a plurality of transmission means 14. Each transmission unit 14 receives the packet distributed by the transmission control unit 13 and transmits it from the corresponding communication line. The image receiver 15 includes a receiving unit 16 that receives each packet transmitted from each transmitting unit 14, and a reconstruction unit 17 that reconstructs original information from each packet received by the receiving unit 16. .
[Selection] Figure 1

Description

  The present invention relates to an information transfer system.

  In recent years, in the information communication technology (ICT), development of a system for quickly transmitting more information has been demanded. For example, in the medical field, by transferring the patient's status to the doctor as an image during transportation by an ambulance, the patient's status that is difficult to express in words can be conveyed in more detail, and an appropriate initial action system can be established. It has been found to be very effective in doing so. In addition, when a large-scale disaster occurs, it is considered that more information can be quickly transmitted by using a broadband communication system, which can contribute to the reduction of damage.

  As a method for transmitting such a large amount of information, it is conceivable to use a plurality of communication lines in parallel. Conventionally, as a technology for transferring information using a plurality of communication lines in parallel, the encoded video information is divided into a plurality of divided data, and the most important data is determined according to the importance of the encoded video information. There is a video information transmission system in which data is transmitted through a plurality of communication lines and less important data is transmitted through a single communication line (see, for example, Patent Document 1).

JP 2003-309594 A

  However, in the video information transmission system described in Patent Document 1, the number of communication lines is adjusted according to the importance, and there is a problem that it cannot be used when transferring information that cannot determine the importance. It was. In addition, since the same most important data is transmitted through multiple communication lines, stable information transfer can be performed, but the transfer speed is not increased compared to the case of using a single communication line. There were also challenges.

  The present invention has been made paying attention to such a problem, and an object of the present invention is to provide an information transfer system capable of stably transferring a large amount of information at high speed irrespective of the presence or absence of importance. Yes.

  In order to achieve the above object, an information transfer system according to the present invention is provided with a plurality of communication lines, transmission control means for dividing information to be transmitted into a plurality of packets, and a plurality corresponding to each communication line, A transmission unit that receives the packet divided by the transmission control unit and transmits the packet from a corresponding communication line; a reception unit that is connected to each communication line and receives each packet transmitted from each transmission unit; and the reception unit Reconstructing means for reconstructing the original information from each packet received in step (i), wherein the transmission control means is configured to distribute all packets to each transmitting means so that they can be transmitted two or more times. It is characterized by being.

  The information transfer system according to the present invention can transmit all packets the same number of times twice or more. For this reason, the risk of loss of all packets to be transmitted can be reduced as compared with the case of transmitting all packets once. This makes it possible to perform stable transfer with a small loss risk regardless of the importance of each packet.

  In addition, by setting the number of times each packet is transmitted less than the number of communication lines used, the transfer speed can be increased compared to the case of using a single communication line, and more information can be transmitted at high speed. Can be transferred. Even when one communication line becomes unable to communicate or the transfer rate decreases, a decrease in transfer rate can be suppressed by distributing a large number of packets to the remaining communication lines. Thus, it can be said that the information transfer system according to the present invention realizes general-purpose data communication capable of transferring any information while suppressing loss risk and a decrease in transfer speed.

  In the information transfer system according to the present invention, each transmission unit and the reception unit are configured to be able to transmit and receive each other, and the reconfiguration unit is configured to receive the original information while receiving each packet by the reception unit. Is configured to transmit a transmission end signal to the transmission control unit via the reception unit and one transmission unit when all the packets that can be reconfigured are gathered, and the transmission control unit When a signal is received, distribution of the information packet being transmitted may be stopped, and a packet of information to be transmitted next may be distributed to each transmission means. In this case, it is not necessary to transmit all packets the same number of times, and transfer efficiency can be improved.

  In the information transfer system according to the present invention, the transmission control means inserts packets in order from the last packet between each packet when arranged from the first packet so that all packets can be transmitted twice. The packets may be arranged, and each packet may be distributed to each transmission means in the arrangement order. In this case, even when the quality of each communication line deteriorates at a certain point in time, the probability that the same packet transmitted twice is lost can be reduced, and the stability is high. When there is no loss, it is quick to gather all the divided packets. Therefore, the transfer efficiency can be further improved by combining with a configuration for transmitting a transmission end signal.

  In the information transfer system according to the present invention, the transmission control unit determines a packet size to be distributed to each transmission unit based on the throughput of each communication line when transmitted by each transmission unit, and each transmission unit determines each packet size according to the packet size. It may be configured to be divided into packets and distributed to each transmission means. In this case, the packet size transmitted on each communication line can be adjusted based on the throughput of each communication line when actually transmitted, and transmission according to the status of each communication line can be performed. For this reason, the risk of packet loss can be reduced, and the stability is high.

  In the information transfer system according to the present invention, each communication line may be composed of a mobile phone line of a different carrier, the information may be composed of image information, and may be transmitted to the receiving means by a user datagram protocol (UDP). . In this case, even if there is a carrier line with a poor communication state, a decrease in transfer rate can be suppressed by distributing a large number of packets to other carrier lines. Since a cellular phone line is used, image information can be stably transferred at high speed regardless of location, and the application range is wide. Since UDP is used as a communication method, the line utilization rate can be increased as compared with communication using confirmation response such as TCP (Transmission Control Protocol). UDP has a higher risk of packet loss than TCP. However, the risk of packet loss can be reduced by transmitting each packet twice or more the same number of times.

  According to the present invention, it is possible to provide an information transfer system capable of stably transferring more information at a high speed regardless of the presence or absence of importance.

It is a block diagram of the information transfer system of embodiment of this invention. It is explanatory drawing which shows the transfer method of each packet of the information transfer system shown in FIG. It is a graph which shows the transfer rate measured with the image receiver in the driving | running | working experiment of the information transfer system shown in FIG. It is a graph which shows the transfer rate of each mobile telephone line in the driving | running | working experiment of the information transfer system shown in FIG. It is a graph which shows the arrival rate of the packet for every file of the information transfer system shown in FIG. It is a graph which shows the arrival rate of the data for every file required in order to reconfigure | reconstruct each image of the information transfer system shown in FIG. It is a graph which shows the packet transmission rate for every file of the information transfer system shown in FIG. It is a graph which shows the transfer rate for every file by the information transfer system (Proposed System) shown in FIG. 1, and FTP. (A) It is a graph which shows the arrival time interval of the packet in the information transfer system (Proposed System) shown in FIG. 1, and (b) the image receiver by FTP.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 9 show an information transfer system according to an embodiment of the present invention.
As shown in FIG. 1, the information transfer system 10 is configured as a system that transfers image information by a UDP transfer method using a plurality of cellular phone lines as communication lines. The information transfer system 10 includes an image acquisition unit 11, an encoding unit 12, a transmission control unit 13, a plurality of transmission units 14, and an image receiver 15.

  As shown in FIG. 1, the image acquisition unit 11 includes a USB camera and can acquire a digital image. The encoding unit 12 includes a computer (Encode PC) and is connected to the image acquisition unit 11. The encoding unit 12 is configured to convert the image information acquired by the image acquisition unit 11 into a JPEG format file.

  The transmission control unit 13 includes a computer (Master PC) and is connected to the encoding unit 12. The transmission control unit 13 receives JPEG format image information from the encoding unit 12, divides the image information into a plurality of packets, and adds a header to each packet to create a transmission packet. Further, as shown in FIG. 2, the transmission control means 13 inserts packets in order from the last packet between each packet when arranged from the first packet so that all created packets can be transmitted twice. Each packet is arranged, and each packet is distributed to each transmission means 14 in the arrangement order.

  As shown in FIG. 1, each transmission means 14 comprises a computer (Gateway PC) and a mobile phone (Cellular Phone), and is provided corresponding to each mobile phone line. Each transmission unit 14 is connected to the transmission control unit 13 by a wireless LAN (Wireless LAN), and is configured to receive the packet distributed by the transmission control unit 13 and transmit it from the corresponding mobile phone line. . Each transmission means 14 always monitors the corresponding cellular phone line, and sends a transmission enable message to the transmission control means 13 when the packet can be transmitted. Each transmission unit 14 measures the time required for transmission each time transmission is performed, and obtains the throughput from the measurement time and the transmitted packet size.

  Each time transmission is performed, the transmission control unit 13 receives the throughput of the transmission unit 14 that has performed transmission. The transmission control means 13 is configured to determine the packet size to be distributed to each transmission means 14 as follows based on the received throughput. First, every time transmission is performed by a certain transmission means 14, a packet having a size larger than that of the previous transmission is transmitted. Next, when a significant drop in the throughput of the transmission means 14 that has performed the transmission occurs, the packet size before the drop in the throughput is determined as the optimum packet size of the transmission means 14 and distributed to each transmission means 14 Size. When the transmission control unit 13 receives a transmittable message from each transmission unit 14, the transmission control unit 13 divides the image information into packets according to the packet size allocated to each transmission unit 14, arranges each packet in the order of transmission, and sets each packet in the arrangement order. Is sent to the corresponding transmission means 14.

  The image receiver 15 (Image Receiver) is composed of a computer, and includes a receiving unit 16 and a reconstruction unit 17. The receiving means 16 is connected to each mobile phone line and configured to receive each packet transmitted from each transmitting means 14. Moreover, the receiving means 16 and each transmission means 14 are comprised so that transmission / reception is mutually possible.

  As shown in FIG. 2, the reconstruction unit 17 is configured to reconstruct the original information from each packet received by the reception unit 16 based on the header information of each packet. In addition, the reconstructing unit 17 receives all the packets that can be reconstructed from the original information while the receiving unit 16 is receiving each packet, through the receiving unit 16 and one transmitting unit 14. A transmission end signal (ack) is transmitted to the transmission control means 13. The reconstructing means 17 does not transmit a transmission end signal when all packets that can reconstruct the original information are not prepared due to packet loss. The reconstruction unit 17 determines that there is a packet loss when the next information packet is received before all the packets that can reconstruct the original information are available.

  The transmission control unit 13 is configured to stop distribution of a packet of information being transmitted when receiving a transmission end signal from the reconfiguration unit 17 and distribute a packet of information to be transmitted next to each transmission unit 14. Yes. In addition, when the transmission control unit 13 distributes all the packets to be transmitted twice before receiving the transmission end signal, the transmission control unit 13 immediately distributes the packet of information to be transmitted next to each transmission unit 14.

Next, the operation will be described.
Since the information transfer system 10 is configured to transmit all packets twice, the risk of loss of all packets to be transmitted can be reduced compared to the case where all packets are transmitted once. . For this reason, it is possible to perform stable transfer with a small loss risk regardless of the importance of each packet. In addition, since each packet is sorted in the order shown in FIG. 2, even if the quality of each mobile phone line deteriorates at a certain point in time, the probability of losing the same packet transmitted twice is reduced. It is more stable. When there is no loss, it is quick to gather all the divided packets, so there is no need to send all the packets twice, and the transfer time can be shortened to increase the transfer efficiency.

  The information transfer system 10 can increase the transfer speed compared to the case of using a single line by setting the mobile phone line to be used to 3 lines or more, and can transfer more information at a high speed. Can do. Even when one mobile phone line becomes unable to communicate or the transfer rate is reduced, a reduction in transfer rate can be suppressed by distributing a large number of packets to the remaining mobile phone lines.

  Since the information transfer system 10 can adjust the packet size transmitted on each mobile phone line based on the throughput of each mobile phone line when it is actually transmitted, transmission according to the situation of each mobile phone line is possible. It can be carried out. When transmission is performed with the maximum packet size that can be transmitted through each mobile phone line, packet loss may occur due to noise or the like depending on the situation of each mobile phone line. In order to cope with such a situation, the information transfer system 10 transmits with a packet size corresponding to the actual situation of each mobile phone line, such as transmitting with a small packet size. Risk can be reduced and stability is high.

  The information transfer system 10 uses a mobile phone line of a different carrier to suppress a decrease in transfer speed by allocating a large number of packets to other carrier lines even if there is a carrier line with a poor communication state. Can do. Since a cellular phone line is used, image information can be stably transferred at high speed regardless of location, and the application range is wide. Since UDP is used as a communication method, the line utilization rate can be increased as compared with communication using confirmation responses such as TCP. In particular, since a delay may be very large in a mobile phone line, UDP is more advantageous than communication using an acknowledgment from the viewpoint of line utilization. UDP has a higher risk of packet loss than TCP, but by transmitting each packet twice, the risk of loss of the packet can be reduced.

  Thus, it can be said that the information transfer system 10 realizes general-purpose data communication capable of transferring any information while suppressing loss risk and a decrease in transfer speed.

  When there is a device that can access a cellular phone line and a wireless LAN by running a DHCP (Dynamic Host Configuration Protocol) daemon in the transmission control means 13, the information transfer system 10 Without requiring device authentication, the number of communication lines can be increased by dynamically adding the devices. This function can be realized by broadcasting a “transferable message”. The information transfer system 10 is different from multihoming in that a communication band can be expanded by dynamically adding devices.

  An image information transfer experiment was performed while the image acquisition unit 11, the encoding unit 12, the transmission control unit 13, and the transmission units 14 were running on a vehicle. Three mobile phone lines of different carriers were used as communication lines. The transfer rate measured by the image receiver 15 at this time is shown in FIG. 3, and the transfer rate of each mobile phone line is shown in FIG. As shown in FIG. 3, in the information transfer system 10, it can be confirmed that a transfer rate of about 1 Mbps is obtained. Further, as shown in FIG. 4, it can be confirmed that each mobile phone line has a transfer rate of about 400 kbps. From this, it can be seen that according to the information transfer system 10, a transfer rate substantially proportional to the number of lines can be obtained.

  An image information transfer experiment was conducted using three mobile phone lines of different carriers as communication lines. There are about 250 transferred image information files. The arrival rate of packets for each file at this time is shown in FIG. 5, and the arrival rate of data for each file necessary to reconstruct each image is shown in FIG. As shown in FIG. 5, the packet arrival rate is at least 58%, and it can be confirmed that more than 40% of packets may be lost. On the other hand, as shown in FIG. 6, it can be confirmed that the data necessary to reconstruct each image has been received 100% in most files.

  This is because the information transfer system 10 performs so-called multiplex transfer in which all packets are transmitted twice, so that even if one of the same packets is lost, necessary data is sent to the image receiver 15. This is because the arrival rate of data necessary for reconstructing each image is higher than the arrival rate of packets. From this, according to the information transfer system 10, it can confirm that the loss risk of a packet can be reduced.

  FIG. 7 shows the packet transmission rate for each file. The packet transmission rate for each file is a ratio between the number of packets when all the packets are transmitted twice for each file and the number of packets actually received by the image receiver 15. As shown in FIG. 7, in the information transfer system 10, when all the packets necessary to reconstruct an image are prepared, the image receiver 15 transmits a transmission end signal to request transmission of the next file. Therefore, it is often the case that all packets are not transmitted twice, and it can be confirmed that a decrease in transfer efficiency is suppressed.

  Note that if transmission is possible without packet loss, the packet transmission rate should be 50%. However, as shown in FIG. 7, the actual packet transmission rate is 55 to 57% even if it is small. Yes. This is considered to be due to a packet transmitted between the time when the image receiver 15 transmits the transmission end signal and the time when the transmission control means 13 receives the transmission end signal.

  A comparison experiment with FTP (File Transfer Protocol), which is one of TCP, was conducted. In the experiment, FTP transfer and transfer by the information transfer system 10 were alternately performed using one mobile phone line, and the transfer rate was obtained based on the transfer time for each file. The result is shown in FIG. FIG. 9 shows packet arrival time intervals at the image receiver 15. As shown in FIG. 8, it can be confirmed that the information transfer system (Proposed System) 10 has a transfer rate approximately twice that of FTP. Further, as shown in FIG. 9, it can be confirmed that the arrival time interval is regularly increased in FTP. This is because FTP uses a confirmation response and a waiting time for the confirmation response occurs. Since the information transfer system 10 uses UDP which does not use an acknowledgment as a communication method, the transfer rate is about twice as fast as FTP.

  The information transfer system 10 does not have to transmit all the packets twice as shown in FIG. 7 even if the multiplex transfer that transmits all the packets twice, the transfer time is doubled. There is nothing. Also, the information transfer system 10 is approximately twice as fast as FTP as shown in FIG. From these, it can be seen that the information transfer system 10 has a higher transfer rate than when all packets are transmitted once by FTP. Since the information transfer system 10 can reduce the risk of packet loss by transmitting all the packets twice, the risk of loss is small and transfer can be performed at a speed higher than that of FTP.

DESCRIPTION OF SYMBOLS 10 Information transfer system 11 Image acquisition means 12 Encoding means 13 Transmission control means 14 Transmission means 15 Image receiver 16 Receiving means 17 Reconfiguration means

Claims (5)

Multiple communication lines,
Transmission control means for dividing information to be transmitted into a plurality of packets;
A plurality of transmission means provided corresponding to each communication line, receiving the packet divided by the transmission control means, and transmitting from the corresponding communication line;
Receiving means connected to each communication line and receiving each packet transmitted from each transmitting means;
Reconstructing means for reconstructing original information from each packet received by the receiving means,
The transmission control means is configured to distribute each packet to each transmission means so that all packets can be transmitted the same number of times twice or more.
Characteristic information transfer system. Each transmitting means and the receiving means are configured to be able to transmit and receive each other,
The reconfiguring means is configured to control the transmission via the receiving means and one transmitting means when all the packets whose original information can be reconstructed are gathered while each packet is received by the receiving means. Configured to transmit a transmission end signal to the means,
The transmission control means is configured to stop distribution of packets of information being transmitted when receiving the transmission end signal and distribute packets of information to be transmitted next to the transmission means.
The information transfer system according to claim 1, wherein:   The transmission control means arranges each packet by inserting packets in order from the last packet between the packets when arranged from the first packet so that all packets can be transmitted twice, and each packet in the arrangement order The information transfer system according to claim 1, wherein the information transfer system is configured so as to be distributed to each transmission means.   The transmission control means determines a packet size to be distributed to each transmission means based on the throughput of each communication line when transmitted by each transmission means, and divides each packet according to the packet size to each transmission means. 4. The information transfer system according to claim 1, wherein the information transfer system is configured to distribute the information. Each communication line consists of a mobile phone line of a different carrier,
The information comprises image information and is transmitted to the receiving means by a user datagram protocol (UDP);
5. The information transfer system according to claim 1, 2, 3 or 4.

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