JP5397226B2 - COMMUNICATION SYSTEM, DATA TRANSMISSION DEVICE, DATA RECEPTION DEVICE, COMMUNICATION METHOD, AND COMMUNICATION PROGRAM - Google Patents

Description

  The present invention relates to a technique for realizing packet communication, and more particularly to a communication system, a data transmission device, a data reception device, a communication method, and a communication program using an error correction code.

  In data communication, there is a possibility that an error may occur in data due to bit inversion in a transmission path or loss due to buffer overflow in a router in a packet network. As a restoration technique for this data error, an automatic repeat request (ARQ: Automatic Repeat Request) for requesting a part to be re-sent to the transmission side by the receiving side, or data is made redundant in advance and a part of the data is sent. A technique such as forward error correction (FEC), which is an encoding technique that can be restored even if an error occurs, is used.

  As an FEC technique, a linear block code is widely used. A typical linear block code is a Reed Solomon code. In the linear block code, the signal length for each block is k (information length), the signal length after FEC is applied is n (code length), and the code of code length n and information length k is (n, k) − It is called a sign. nk is called redundancy. Hereinafter, this nk value is referred to as redundancy.

  When ARQ is used as a data restoration technique, the integrity of data is guaranteed, but at the time of retransmission, a round trip delay time is delayed until the retransmission is completed. There is a problem that it is not suitable for traffic in which real-time characteristics are important. In addition, when the error rate increases, the retransmitted data also has a higher probability that an error will occur, and re-transmission is required. Therefore, there is a problem that it takes time to completely recover.

  When FEC is used as a data restoration technique, the redundancy is fixed, so that the redundancy may not be suitable for the network error rate. For example, if the FEC redundancy is insufficient, the data cannot be completely restored, and if the FEC redundancy is large, an extra network bandwidth is used.

As a dynamic FEC system for calculating the optimum redundancy of FEC based on network conditions, for example, Japanese Patent Laid-Open No. 2006-287928, “O. Tickoo, V. Subramanian, S. Kalyanaraman, and KKRamakrishnan,“ LT-TCP : End-to-End Framework to Improve TCP Performance over Networks with Lossy Channels ”, in Proc. Of Thirteenth International Workshop on Quality of Service (IWQoS 2005), Passau, Germany, June 2005” (hereinafter referred to as Reference 1) The disclosed LT-TCP, “M. Miyoshi, M. Sugano, and M. Murata,“ Improving TCP Performance for Wireless Cellular Networks by Adaptive FEC Combined with Explicit Loss Notification ”, IEICE transactions on communications, Vol. 85, No. .10 (20021001), pp.2208-2213, Oct. 2002 "(hereinafter referred to as Document 2), Japanese Patent Application Laid-Open No. 2006-129277 has been proposed.
In a communication system based on LT-TCP, a bit error such as radio and a loss due to congestion are distinguished by ECN (Explicit Congestion Notification) added to a TCP (Transmission Control Protocol) header at the time of congestion in the repeater, and according to the bit error. Send data with redundancy. The ECN is described in “S. Floyd, D. Black,“ RFC 3168: The Addition of Explicit Congestion Notification (ECN) to IP ”, IETF, Sep. 2001”.

Also, in Reference 2, a bit error such as radio and loss due to congestion are distinguished by ELN (Explicit Loss Notification) added to the TCP header when an error that is not congestion occurs in the repeater, and the redundancy according to the bit error A system for transmitting data is disclosed. ELN is described in “H. Balakrishnan, RH Katz,“ Explicit Loss Notification and Wireless Web Performance ”, in Proc. Of IEEE GLOBECOM '98 Internet Mini-Conference, Nov. 1998”.
Japanese Patent Laid-Open No. 2006-129277 discloses a communication state called a transmission error rate and a predicted value of a data transfer rate at which data transfer is performed based on a delivery confirmation packet, and real-time transmission is performed according to the measured communication state. A system is disclosed in which the code rate of stream data and the redundancy of FEC that are required are changed.

  In any of Japanese Patent Laid-Open Nos. 2006-287928, 1, 2, and 2006-129277, redundancy control based on network conditions means redundancy control for transmission errors. This is not redundancy control for packet loss due to congestion caused by buffer overflow in the device.

Japanese Patent Laid-Open No. 10-079724 discloses a communication system that controls the communication speed based on the transmission error rate. In this communication system, a wireless terminal receives and decodes a packet including an error correction code transmitted from a base station, and transmits the number of error bits subjected to error correction to the base station. The base station controls the information transmission rate based on the notification information from the wireless terminal.
Japanese Patent Laid-Open No. 2005-341361 discloses a communication system that controls the communication speed based on statistical information such as delay time and the number of error packets. In this communication system, the transmitting terminal device transmits FEC encoded data to the receiving terminal device, and the receiving terminal device receives statistics such as the delay time and the number of error packets in the entire network and the radio link when receiving data. Information is generated and transmitted as feedback information to the transmission terminal device. The transmission terminal apparatus determines the transmission rate based on the feedback information.

  The first problem of the techniques disclosed in JP 2006-287728 A, JP 2006-129277 A, JP 10-079724 A, JP 2005-341361 A, Reference 1 and Reference 2 is as follows: When a protocol that performs congestion control such as TCP or DCCP (Datagram Congestion Control Protocol) is used on a layer that has a mechanism that restores packet loss due to congestion based on dynamic FEC technology, the congestion window It continues to extend beyond the capacity (bandwidth product + bottleneck buffer), and eventually causes a burst loss that cannot be recovered by FEC. The reason is that the congestion loss of the upper layer does not work because the congestion loss is concealed by the FEC.

  The second problem of the technology disclosed in JP 2006-287728 A, JP 2006-129277 A, JP 10-079724 A, JP 2005-341361 A, Reference 1 and Reference 2 is as follows: Even if the same congestion control is performed on the same dynamic FEC algorithm, fairness between sessions cannot be maintained. The reason is that the congestion window is likely to increase because the loss rate after correction of a session whose redundancy is increased by dynamic FEC first becomes small.

[Object of invention]
An object of the present invention is to provide a communication system capable of performing congestion control that does not exceed the network capacity, and improving fairness between sessions even if the same congestion control is performed on the same dynamic FEC algorithm, and data transmission An object is to provide a device, a data receiving device, a communication method, and a communication program.

  The communication system according to the present invention includes a restoration status information acquisition unit that acquires information on the restoration status of the packet using an error correction code added to a packet transmitted and received via the communication network, and a restoration status of the packet using the error correction code. And a restoration status determination means for selecting whether to perform communication control processing at normal time or communication control processing at the time of packet loss recovery due to congestion, and when performing the normal communication control processing is selected. When the communication control means for normal time that performs communication speed control using congestion information and the communication control process at the time of restoration are selected, the communication speed is reduced or lower than the normal time. And a restoration-time communication control means for reducing the increase width.

  Further, the data transmission device of the present invention is a packet that transmits a packet with the error correction code added thereto to a data reception device that receives the packet via a communication network and corrects the error of the packet using an error correction code. Whether to perform normal communication control processing according to the restoration status information acquisition means for acquiring packet restoration status information by the error correction code in the data receiving device, and the packet restoration status by the error correction code A restoration status determination means for selecting whether to perform communication control processing when restoring packet loss due to congestion, and communication speed control using congestion information when the normal communication control processing is selected. When it is selected that the normal-time communication control means and the communication control process at the time of restoration are selected, the communication speed is reduced or the communication speed is lower than the normal time. Is characterized in further comprising a restoring time of communication control means for reducing the increment of the velocity.

  Further, the data receiving apparatus of the present invention includes a packet receiving means for receiving the packet via a communication network from a data transmitting apparatus for transmitting a packet with an error correction code added thereto, and an error of the packet received by the packet receiving means. Redundant decoding means for correcting using the error correction code, and performing normal communication control processing according to the restoration status of the packet by the error correction code in the redundant decoding means or at the time of restoration of packet loss due to congestion A restoration status determination means for selecting whether to perform communication control processing, a normal time communication control means for performing communication speed control using congestion information when the normal communication control processing is selected, and When it is selected to perform the communication control process at the time of restoration, it is possible to reduce the communication speed or reduce the increase rate of the communication speed compared to the normal time. It is characterized in further comprising a time of communication control means.

  The data transmission device of the present invention includes a packet transmission means for transmitting the packet to a redundancy device that adds an error correction code to a packet received via a communication network, and a packet received from the redundancy device. Reconstruction status information acquisition means for correcting information using the error correction code and acquiring information on the recovery status of the packet by the error correction code in a redundant decoding device that transmits the corrected packet to a data reception device; Restoration status determination means for selecting whether to perform normal communication control processing or to perform communication control processing at the time of recovery of packet loss due to congestion according to the restoration status of the packet by error correction code, and the normal communication control processing When communication is selected, normal communication control means for performing communication speed control using congestion information and communication control processing at the time of restoration are performed. If it is selected and is characterized in that it comprises a recovery time of communication control means for reducing the normal increment of to or the communication speed decreases the communication speed than during.

  Further, the communication method of the present invention includes a restoration status information acquisition step for acquiring information on the restoration status of the packet by an error correction code added to a packet transmitted / received via a communication network, and a restoration of the packet by the error correction code. A restoration status determination step for selecting whether to perform communication control processing at normal time or to perform communication control processing at the time of restoration of packet loss due to congestion according to the situation, and to perform the communication control processing at the normal time are selected In this case, when it is selected that the normal time communication control step for performing the communication speed control using the congestion information and the communication control process at the time of restoration are selected, the communication speed is reduced or compared with the normal time. A restoration communication control step for reducing the rate of increase in speed.

  In addition, the communication program of the data transmission device of the present invention provides a packet in which the error correction code is added to a data reception device that receives a packet via a communication network and corrects an error of the packet using an error correction code. A packet transmission step for transmitting the packet, a restoration status information acquisition step for acquiring packet restoration status information by the error correction code, and whether or not a normal communication control process is performed according to the packet restoration status by the error correction code A restoration status determination step for selecting whether to perform communication control processing when restoring packet loss due to congestion, and communication speed control using congestion information when the normal communication control processing is selected. When it is selected to perform the communication control process at the normal time and the communication control process at the time of restoration, the communication speed is decreased than the normal time. Or a recovery time of communication control step of decreasing the increment of the communication speed, is characterized in causing a computer to execute.

  Further, the communication program of the data receiving apparatus of the present invention receives the packet from the data transmitting apparatus that transmits the packet with the error correction code added via the communication network, and the packet receiving step receives the packet. A redundant decoding step for correcting an error of the packet using the error correction code, and a normal communication control process is performed according to a restoration status of the packet by the error correction code in the redundant decoding step, or a packet loss due to congestion A restoration status determination step for selecting whether to perform communication control processing at the time of restoration, and normal time communication control for performing communication speed control using congestion information when the normal communication control processing is selected. And when the communication control process at the time of restoration is selected, the communication speed is reduced compared to the normal time. Or or a recovery time of communication control step of decreasing the increment of the communication speed, is characterized in causing a computer to execute.

  In the present invention, by providing restoration status information acquisition means, restoration status judgment means, normal time communication control means, and restoration time communication control means, the communication speed is changed according to the restoration status of the packet by the error correction code. The first effect of the present invention with such a configuration is that, even if the FEC layer exists in the lower layer, the congestion control layer that is the upper layer can perform congestion control that does not exceed the network capacity. The reason is that by making the restoration state of the FEC layer, which is a lower layer, available from the congestion control layer, which is an upper layer, the communication speed can be lowered according to the restoration state. The second effect of the present invention is that fairness between sessions can be improved even if the same congestion control is performed on the same dynamic FEC algorithm. The reason for this is to reduce the communication speed according to the restoration state and redundancy by making the restoration state and redundancy of the FEC layer, which is a lower layer, available from the congestion control layer, which is an upper layer.

FIG. 1 is a block diagram showing a configuration of a communication apparatus of a communication system according to the first embodiment of the present invention. FIG. 2 is a flowchart showing the operation of the communication apparatus according to the first embodiment of the present invention. FIG. 3 is a block diagram showing a configuration of a communication system according to the second embodiment of the present invention. FIG. 4 is a block diagram showing the configuration of the data transmitting apparatus and data receiving apparatus of the communication system according to the second embodiment of the present invention. FIG. 5 is a flowchart showing the operation of the data transmission apparatus of the communication system according to the second embodiment of the present invention. FIG. 6 is a flowchart showing the operation of the data receiving apparatus of the communication system according to the second embodiment of the present invention. FIG. 7 is a block diagram showing the configuration of the data transmitting apparatus and data receiving apparatus of the communication system according to the third embodiment of the present invention. FIG. 8 is a flowchart showing the operation of the data transmission apparatus of the communication system according to the third embodiment of the present invention. FIG. 9 is a flowchart showing the operation of the data receiving apparatus of the communication system according to the third embodiment of the present invention. FIG. 10 is a block diagram showing the configuration of the data transmitting apparatus and data receiving apparatus of the communication system according to the fourth embodiment of the present invention. FIG. 11 is a flowchart showing the operation of the data transmission apparatus of the communication system according to the fourth example of the present invention. FIG. 12 is a flowchart showing the operation of the data receiving apparatus of the communication system according to the fourth embodiment of the present invention. FIG. 13 is a block diagram showing a configuration of a communication system according to the fifth example of the present invention. FIG. 14 is a block diagram showing the configuration of the data transmission device, redundancy device, redundant decoding device, and data reception device of the communication system according to the fifth example of the present invention. FIG. 15 is a flowchart showing the operation of the data transmitting apparatus of the communication system according to the fifth example of the present invention. FIG. 16 is a flowchart showing the operation of the redundancy apparatus for the communication system according to the fifth example of the present invention. FIG. 17 is a flowchart showing the operation of the redundant decoding device of the communication system according to the fifth example of the present invention. FIG. 18 is a flowchart showing the operation of the data receiving apparatus of the communication system according to the fifth example of the present invention. FIG. 19 is a block diagram showing the configuration of the data transmitting apparatus, redundancy apparatus, redundant decoding apparatus, and data receiving apparatus of the communication system according to the sixth embodiment of the present invention. FIG. 20 is a flowchart showing the operation of the redundant decoding device of the communication system according to the sixth example of the present invention. FIG. 21 is a flowchart showing the operation of the data receiving apparatus of the communication system according to the sixth embodiment of the present invention. FIG. 22 is a block diagram showing the configuration of the data transmission device, redundancy device, redundant decoding device, and data reception device of the communication system according to the seventh embodiment of the present invention. FIG. 23 is a flowchart showing the operation of the data transmitting apparatus of the communication system according to the seventh example of the present invention. FIG. 24 is a flowchart showing the operation of the redundant decoding device of the communication system according to the seventh example of the present invention. FIG. 25 is a flowchart showing the operation of the data receiving apparatus of the communication system according to the seventh embodiment of the present invention.

[First embodiment]
Next, the best embodiment for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a communication apparatus of a communication system according to the first embodiment of the present invention. Whether the communication apparatus 1 according to the present embodiment performs a normal communication control process according to the restoration status information acquisition unit 2 that acquires information on the restoration status of a packet using an error correction code, and the restoration status of the packet using an error correction code The restoration status determination unit 3 that selects whether to perform communication control processing when restoring packet loss due to congestion, and communication speed control using congestion information when it is selected to perform normal communication control processing A normal-time communication control unit 4 and a restoration-time communication control unit 5 that reduces the communication speed or reduces the increase rate of the communication speed compared to the normal time when the communication control process at the time of restoration is selected. Is provided.

  As the communication device 1, a data transmission device that transmits a packet to which an error correction code is added to a data reception device via a communication network, or a packet that is received via the communication network and corrects the packet error using the error correction code A data receiving apparatus that can be considered.

  The restoration status information acquisition unit 2 acquires packet restoration status information using an error correction code. If the communication device 1 is a data transmission device, the restoration status information acquisition unit 2 acquires information on the restoration status of a packet using an error correction code in the data reception device. If the communication device 1 is a data receiving device, the restoration status information acquisition unit 2 acquires information on the restoration status of the packet by the error correction code in the own device.

  The restoration status determination unit 3 selects whether to use the normal time communication control unit 4 or the restoration time communication control unit 5 as means for controlling the communication speed according to the restoration status of the packet by the error correction code. The restoration status determination unit 3 selects the normal-time communication control unit 4 when determining that the packet can be recovered using the error correction code, and selects the recovery-time communication control unit 5 when determining that the packet cannot be recovered. .

  The normal time communication control unit 4 controls the communication speed using the congestion information when the error correction code is not used. The congestion information is packet reception information indicating the status of packet loss on the receiving side, or packet reception information and transmission delay information indicating the status of packet loss on the receiving side. When congestion occurs in the communication network, the queue length of the buffer of the repeater is increased and the transmission delay is increased. If the queue length increases beyond the limit value, the packet is discarded and lost. Therefore, the congestion state can be grasped from the packet reception information and the transmission delay information, and communication control for avoiding the congestion can be performed.

  The restoration time communication control unit 5 performs communication speed control different from that of the normal time communication control unit 4. That is, the restoration time communication control unit 5 may decrease the communication speed as compared with the normal time communication control unit 4 or may decrease the increase rate of the communication speed.

Next, the operation of the present embodiment will be described in detail with reference to FIG. 1 and the flowchart of FIG. 2 showing the operation of the communication apparatus 1.
The restoration status information acquisition unit 2 of the communication device 1 acquires packet restoration status information using an error correction code (step A2 in FIG. 2).

  The restoration status determination unit 3 selects whether to use the normal-time communication control unit 4 or the restoration-time communication control unit 5 as means for controlling the communication speed based on the restoration status of the packet by the error correction code (step A3). Since the selection operation of the restoration status determination unit 3 has been described above, a description thereof will be omitted.

  When the restoration-time communication control unit 5 is selected by the restoration status determination unit 3, the restoration-time communication control unit 5 performs communication speed control processing at the time of packet restoration (step A4). When the normal communication control unit 4 is selected, the normal communication control unit 4 performs a normal communication speed control process (step A5).

  When the communication device 1 is a data transmission device, the communication speed control process means that a packet is generated based on the communication speed calculated by the communication control units 4 and 5. When the communication device 1 is a data receiving device, the communication speed control process transmits information on the communication speed calculated by the communication control units 4 and 5 to the data transmitting device, and generates a packet based on the communication speed to the data transmitting device. It means that

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 3 is a block diagram showing the configuration of the communication system according to the second embodiment of the present invention. In the present embodiment, the first embodiment will be described more specifically. In this embodiment, when data is transmitted from the data transmission device 1101-1 to the data reception device 1101-2, a case where the data passes through the communication network 1101-3 is assumed, and processing in this case will be described.

Referring to FIG. 4, the communication system according to the present embodiment includes a data transmission device 1101-1 that is a device that transmits data, and a data reception device 1101-2 that receives data from the data transmission device 1101-1. .
The data transmission device 1101-1 includes a communication control unit 1101-1-100, a packet generation unit 1101-1-1, a redundancy unit 1101-1-2, a packet transmission unit 1101-1-3, and a packet reception. A restoration status information receiving unit 1101-1-11 is included. The communication control unit 1101-1-1-100 includes a normal-time communication control unit 1101-1-101, a restoration-time communication control unit 1101-1-102, and a restoration status determination unit 1101-1-104.

  The packet reception / restoration status information reception unit 1101-1-11 constitutes a restoration status information acquisition unit. The packet reception / restoration status information reception unit 1101-1-11 receives the packet reception / restoration status information from the data reception device 1101-2. The packet reception / restoration status information is information indicating the status of packet restoration by the error correction code. The packet reception information after restoration by the error correction code and the restoration information by the error correction code, or the packet reception before and after the restoration by the error correction code. Information.

  The packet reception information includes one or more of information indicating a packet reception location and information indicating a loss location. The packet reception point indicates the position of the received packet without loss, and the loss point indicates the position of the lost packet. The restoration information by the error correction code is at least one of a flag indicating whether or not the packet has been restored by the error correction code, information on the restoration location indicating the position of the restored packet, the number of packet restorations, and the packet restoration rate including.

  Note that the network information that the communication network is congested from the communication network 1101-3 (the packet is discarded by the repeater in the network) and the occurrence of congestion is close to the packet reception / restoration status information (relay in the network) Network information that the packet queuing buffer has exceeded the threshold value) or network information that the packet was discarded due to a transmission error may be added to the packet reception / restoration status information. .

The communication control unit 1101-1-1-100 controls the communication speed according to the packet reception / restoration status information. The communication control unit 1101-1-100 will be described in detail.
The restoration status determination unit 1101-1-1-104 uses the normal time communication control unit 1101-1-101 as means for controlling the communication speed according to the state of the packet reception / restoration status information, or the restoration time communication control unit 1101-1. Select whether to use -102.

  The conditions for selecting the normal-time communication control unit 1101-1-101 depending on the state of the packet reception / restoration status information include that the packet is restored by an error correction code, that the number of restored packets is equal to or greater than a threshold, or It is conceivable that the restoration rate is equal to or greater than a threshold value. If these conditions are not met, the restoration time communication control unit 1101-1-102 may be selected.

  When packet reception information after restoration by error correction code and restoration information by error correction code are used as packet reception / restoration status information, whether or not a packet has been restored by error correction code has restoration information by error correction code Judgment can be made by whether or not. In addition, when packet reception information before and after restoration using an error correction code is used as packet reception / restoration status information, whether or not a packet is restored using an error correction code is whether there is a difference in packet reception information before and after restoration. Can be judged.

  When packet reception information after restoration using an error correction code and restoration information using an error correction code are used as packet reception / restoration status information, whether or not the number of restorations of a packet is greater than or equal to a threshold value can be determined by counting the number of restoration points or restoring It can be judged by using the information of the number. In addition, when packet reception information before and after restoration by error correction code is used as packet reception / restoration status information, the restored location can be identified by comparing the packet reception location before and after restoration or the loss location before and after restoration. The number of restorations can be counted, so that it can be determined whether or not the number of restorations is equal to or greater than a threshold value.

  When packet reception information after restoration by error correction code and restoration information by error correction code are used as packet reception / restoration status information, whether or not the restoration rate of the packet is equal to or greater than a threshold is determined by the restoration rate, the number of restorations, This can be determined by calculating the restoration rate from the restoration location. In addition, when packet reception information before and after restoration by error correction code is used as packet reception / restoration status information, the restoration rate can be calculated by comparing the packet reception location before and after restoration or the loss location before and after restoration. Thus, it can be determined whether or not the restoration rate is equal to or higher than the threshold value.

Note that the restoration status determination unit 1101-1-1-104, when it is clear from the packet reception information after restoration by the error correction code that a packet loss has occurred, the normal-time communication control unit 1101-1. -101 may be selected.
In addition, when the packet reception / restoration status information includes information indicating that the packet is in a congested state or that congestion is almost occurring, the restoration status determining unit 1101-1-104 restores the communication control unit 1101-1-102 at the time of restoration. When such information is not included, the normal time communication control unit 1101-1-101 may be selected.

  In addition, when the packet reception / restoration status information includes information indicating that the packet has been discarded due to a transmission error, the restoration status determination unit 1101-1-1-104 selects the normal-time communication control unit 1101-1-101. When such information is not included, the restoration time communication control unit 1101-1-1-102 may be selected.

  The normal-time communication control unit 1101-1-101 controls the communication speed using the congestion information when the error correction code is not used. The congestion information is packet reception information indicating the status of packet loss on the receiving side, or packet reception information and transmission delay information indicating the status of packet loss on the receiving side. When congestion occurs in the communication network, the queue length of the buffer of the repeater is increased and the transmission delay is increased. If the queue length increases beyond the limit value, the packet is discarded and lost. Therefore, the congestion state can be grasped from the packet reception information and the transmission delay information, and communication control for avoiding the congestion can be performed.

  When the communication control when the error correction code is not used as the protocol communication control is not defined, the communication speed control processing by the normal time communication control unit 1101-1-101 is determined by the restoration status determination unit 1101-1-1-104. It refers to the communication speed control process corresponding to one of the states to be performed. As the communication speed, a data transmission amount per unit time (referred to as a rate) or a data transmission amount per round trip time (referred to as a congestion window) is used.

  The restoration time communication control unit 1101-1-102 performs communication speed control different from the normal time communication control unit 1101-1-1-101. That is, the restoration time communication control unit 1101-1-102 may decrease the communication speed compared to the normal time communication control unit 1101-1-101. Further, the restoration time communication control unit 1101-1-102 may decrease the increase rate of the communication speed.

  The communication speed reduction range and the communication speed increase range may be values depending on the number of restorations and the restoration rate. Examples of values that depend on the number of restorations and the restoration rate include values that are proportional to the number of restorations and the restoration rate. In addition, when dynamic FEC that dynamically adjusts redundancy is used in the redundancy unit 1101-1-2 or when the redundancy is different for each communication control, the reduction rate of the communication speed, the communication speed A value corresponding to the redundancy may be used as the decrease width of the increase width. As an example of a value corresponding to the redundancy, there is a value proportional to the redundancy.

The packet generation unit 1101-1-1 generates a packet based on the communication speed calculated by the communication control unit 1101-1-100.
The redundancy unit 1101-1-2 adds an error correction code to the packet generated by the packet generation unit 1101-1-1.
The packet transmission unit 1101-1-3 transmits the packet made redundant by the redundancy unit 1101-1-2 to the data reception device 1101-2.

The data reception device 1101-2 includes a packet reception unit 1101-2-1, a redundant decoding unit 1101-2-2, a packet reception / restoration status information calculation unit 1101-2-3, and packet reception / restoration status information. And a transmission unit 1101-2-4.
The packet receiving unit 1101-2-1 receives a packet from the data transmission device 1101-1.
The redundant decoding unit 1101-2-2 decodes the error correction code of the data received by the packet receiving unit 1101-2-1 and restores the lost packet.

The packet reception / restoration status information calculation unit 1101-2-3 calculates packet reception / restoration status information from the reception status in the packet reception unit 1101-2-1 and the restoration status in the redundant decoding unit 1101-2-2. To do.
The packet reception / restoration status information transmission unit 1101-2-4 transmits the packet reception / restoration status information generated by the packet reception unit calculation unit 1101-2-3 to the data transmission device 1101-1.

Next, the overall operation of this embodiment will be described in detail with reference to FIG. 4, the flowchart of FIG. 5 showing the operation of the data transmission device 1101-1, and the flowchart of FIG. 6 showing the operation of the data reception device 1101-2. To do.
The packet reception / restoration status information reception unit 1101-1-11 of the data transmission device 1101-1 receives the packet reception / restoration status information transmitted from the data reception device 1101-2 (step A102 in FIG. 5).

  Whether the restoration status determination unit 1101-1-104 of the communication control unit 1101-1-100 uses the normal-time communication control unit 1101-1-101 as a means for controlling the communication speed based on the packet reception / restoration status information. Then, whether to use the restoration time communication control unit 1101-1-102 is selected (step A103). Since the selection operation of the restoration status determination unit 1101-1-1-104 has been described above, a description thereof will be omitted.

  When the restoration status control unit 1101-1-102 is selected by the restoration status determination unit 1101-1-104, the restoration time communication control unit 1101-1-102 calculates the communication speed at the time of packet restoration (step A104). ). When the normal time communication control unit 1101-1-101 is selected, the normal time communication control unit 1101-1-1-101 calculates a normal communication speed (step A105).

  After calculating the communication speed, the packet generation unit 1101-1-1 generates a packet based on the calculated communication speed (step A106). The redundancy unit 1101-1-2 adds an error correction code to the generated packet (step A107). The packet transmission unit 1101-1-3 transmits the packet with the error correction code added to the data reception device 1101-2 (step A108).

Next, the packet reception unit 1101-2-1 of the data reception device 1101-2 receives the packet transmitted from the data transmission device 1101-1 via the communication network 1101-3 (step A202 in FIG. 6).
Redundant decoding section 1101-2-2 restores the portion of the packet received by packet receiving section 1101-2-1 using the error correction code (step A203).

The packet reception / restoration status information calculation unit 1101-2-3 uses a packet after restoration by an error correction code based on the reception status in the packet reception unit 1101-2-1 and the restoration status in the redundant decoding unit 1101-2-2. The reception information and the restoration information by the error correction code, or the packet reception information before and after the restoration by the error correction code are acquired, and the packet reception / restoration status information is calculated (step A204).
The packet reception / restoration status information transmission unit 1101-2-4 transmits the packet reception / restoration status information to the data transmission device 1101-1 (step A205).

  In this embodiment, the packet reception status information and the packet restoration status information may be transmitted from the data reception device 1101-2 to the data reception 1101-1 in different packets.

[Third embodiment]
Next, a third embodiment of the present invention will be described in detail with reference to the drawings. FIG. 7 is a block diagram showing the configuration of the data transmitting apparatus and data receiving apparatus of the communication system according to the third embodiment of the present invention. In the present embodiment, the first embodiment will be described more specifically. In the present embodiment, the data transmission device 1201-1 is used instead of the data transmission device 1101-1 of FIG. 3, and the data reception device 1201-2 is used instead of the data reception device 1101-2. When data is sent from 1 to the data receiving device 1201-2, a case where the data passes through the communication network 1101-3 is assumed, and processing in this case will be described.

Referring to FIG. 7, the communication system according to the present embodiment includes a data transmission apparatus 1201-1 that is an apparatus that transmits data, and a data reception apparatus 1201-2 that receives data from the data transmission apparatus 1201-1. .
The data transmission device 1201-1 includes a communication control unit 1201-1-100, a packet generation unit 1201-1-1, a redundancy unit 1201-1-2, a packet transmission unit 1201-1-3, and statistical information. Receiving unit 1201-1-12. The communication control unit 1201-1-1-100 includes a normal-time communication control unit 1201-1-101, a restoration-time communication control unit 1201-1-102, and a restoration status determination unit 1201-1-104.

  The packet generation unit 1201-1-1, the redundancy unit 1201-1-2, and the packet transmission unit 1201-1-3 are respectively the packet generation unit 1101-1-1 and the redundancy unit 1101-1 of the second embodiment. 2. Since it is the same as that of the packet transmission unit 1101-1-3-, detailed description is omitted.

  The statistical information receiving unit 1201-1-12 constitutes a restoration status information acquisition unit. The statistical information reception unit 1201-1-12 receives packet reception / restoration statistical information from the data reception device 1201-2. The packet reception / restoration statistical information is statistical information on the restoration status of the packet by the error correction code, and is obtained by statistically processing the packet reception information after restoration by the error correction code for a certain time and the restoration information by the error correction code, or This is a statistically processed packet reception information before and after restoration by an error correction code.

  The packet reception statistical information includes one or more of the number of transmitted packets and the number of received packets at a certain time, the number of transmitted / received packets, the number of packet losses, the packet loss size, and the packet loss rate. The restoration statistical information by the error correction code includes at least one of a flag indicating whether or not the packet has been restored by the error correction code, the number of packet restorations, and the packet restoration rate.

  The restoration status judgment unit 1201-1-104 of the communication control unit 1201-1-100 uses the normal-time communication control unit 1201-1-101 as compared to the restoration status judgment unit 1101-1-104 of the second embodiment. The difference is that statistical information about packet reception is used instead of packet reception / restoration status information to determine whether to use communication control 1201-1-102 during restoration, but the other points are the same.

  The normal-time communication control unit 1201-1-101 and the restoration-time communication control unit 1201-1-102 of the communication control unit 1201-1-100 are respectively a normal-time communication control unit 1101-1-101 and a restoration-time unit of the second embodiment. Compared with the time communication control unit 1101-1-1-102, it is different in that the packet reception / restoration status information is used instead of the packet reception / restoration status information for the calculation of the communication speed, but the other points are the same. Description is omitted.

The data reception device 1201-2 includes a packet reception unit 1201-2-1, a redundant decoding unit 1201-2-2, a packet reception / restoration statistical information calculation unit 1201-2-5, and a statistical information transmission unit 1201-. 2-6.
The packet reception unit 1201-2-1 receives a packet from the data transmission device 1201-1.
The redundant decoding unit 1201-2-2 decodes the error correction code of the data received by the packet receiving unit 1201-2-1 and restores the lost packet.

The packet reception / restoration statistical information calculation unit 1201-2-5 calculates packet reception / restoration statistical information from the reception status in the packet reception unit 1201-2-1 and the restoration status in the redundant decoding unit 1201-2-2. To do.
The statistical information transmission unit 1201-2-6 transmits the packet reception / restoration statistical information generated by the packet reception / restoration statistical information calculation unit 1201-2-5 to the data transmission device 1201-1.

Next, the overall operation of this embodiment will be described in detail with reference to FIG. 7, the flowchart of FIG. 8 showing the operation of the data transmission apparatus 1201-1, and the flowchart of FIG. 9 showing the operation of the data reception apparatus 1201-2. To do.
The statistical information reception unit 1201-1-12 of the data transmission device 1201-1 receives the packet reception / restoration statistical information transmitted from the data reception device 1201-2 (step B102 in FIG. 8).

  Whether the restoration status determination unit 1201-1-104 of the communication control unit 1201-1-1-100 uses the normal-time communication control unit 1201-1-101 as means for controlling the communication speed based on the packet reception / restoration statistical information. Then, it is selected whether to use the restoration time communication control 1201-1-102 (step B103). Since the selection operation of the restoration status determination unit 1201-1-104 has been described above, a description thereof will be omitted.

  When the restoration status control unit 1201-1-102 is selected by the restoration status determination unit 1201-1-104, the restoration time communication control unit 1201-1-102 calculates the communication speed at the time of packet restoration (step B104). ). When the normal time communication control unit 1201-1-101 is selected, the normal time communication control unit 1201-1-101 calculates the normal communication speed (step B105).

  After calculating the communication speed, the packet generation unit 1201-1-1 generates a packet based on the calculated communication speed (step A106). The redundancy unit 1201-1-2 adds an error correction code to the generated packet (step A107). The packet transmission unit 1201-1-3 transmits the packet with the error correction code added to the data reception device 1201-2 (step A108).

The packet reception unit 1201-2-1 of the data reception device 1201-2 receives the packet transmitted from the data transmission device 1201-1 (step A202 in FIG. 9).
Redundant decoding section 1201-2-2 restores the portion of the packet received by packet receiving section 1201-2-1 using the error correction code (step A203).

The packet reception / restoration statistical information calculation unit 1201-2-5 calculates a packet after restoration using an error correction code based on the reception situation in the packet reception unit 1201-2-1 and the restoration situation in the redundant decoding unit 1201-2-2. The reception information and the restoration information by the error correction code, or the packet reception information before and after the restoration by the error correction code are acquired, and the packet reception / restoration statistical information at a certain time is calculated (step B204).
The statistical information transmission unit 1201-2-6 transmits packet reception / restoration status information to the data transmission device 1201-1 (step B205).

In this embodiment, the packet reception statistical information and the packet restoration statistical information may be transmitted from the data reception device 1101-2 to the data transmission device 1101-1 in different packets.
Next, the effect of the present embodiment will be described. In this embodiment, packet loss information is reported as statistical information from the reception side to the transmission side, so that the processing cost on the transmission side can be reduced compared to the second embodiment.

[Fourth embodiment]
Next, a fourth embodiment of the present invention will be described in detail with reference to the drawings. FIG. 10 is a block diagram showing the configuration of the data transmitting apparatus and data receiving apparatus of the communication system according to the fourth embodiment of the present invention. In the present embodiment, the first embodiment will be described more specifically. In this embodiment, the data transmission device 1301-1 is used instead of the data transmission device 1101-1 of FIG. 3, and the data reception device 1301-2 is used instead of the data reception device 1101-2. When data is sent from 1 to the data receiving device 1301-2, a case where the data passes through the communication network 1101-3 is assumed, and processing in this case will be described.

Referring to FIG. 10, the communication system according to the present embodiment includes a data transmission device 1301-1 that is a device that transmits data, and a data reception device 1301-2 that receives data from the data transmission device 1301-1. .
The data transmission device 1301-1 includes a packet generation unit 1301-1-1, a redundancy unit 1301-1-2, a packet transmission unit 1301-1-3, and a communication speed information reception unit 1301-1-13. Including.

The communication speed information receiving unit 1301-1-13 receives the communication speed information from the data receiving device 1301-2.
The packet generation unit 1301-1-1 generates a packet based on the communication speed information received by the communication speed information reception unit 1301-1-13.

The redundancy unit 1301-1-2 adds an error correction code to the packet generated by the packet generation unit 1301-1-1.
The packet transmission unit 1301-1-3 transmits the packet made redundant by the redundancy unit 1301-1-2 to the data reception device 1301-2.

  The data reception device 1301-2 includes a packet reception unit 1301-2-1, a redundant decoding unit 1301-2-2, a communication control unit 1301-2-100, a communication rate information transmission unit 1301-2-6, including. The communication control unit 1301-2-100 includes a normal time communication control unit 1301-2-101, a restoration time communication control unit 1301-2-102, and a restoration status determination unit 1301-2-104.

The packet receiving unit 1301-2-1 receives a packet from the data transmission device 1301-1.
The redundant decoding unit 1301-2-2 decodes the error correction code of the data received by the packet receiving unit 1301-2-1 and restores the lost packet.

  The restoration status determination unit 1301-2-104 of the communication control unit 1301-2-100 constitutes a restoration status information acquisition unit and a restoration status determination unit. The restoration status determination unit 1301-2-104 uses the normal time communication control unit 1301-2-101 or the restoration time communication control 1301-2-1, as compared with the restoration status judgment unit 1101-1-104 of the second embodiment. 102 is different from the packet reception / restoration status information in that it uses information from the packet receiving unit 1301-2-1 and information from the redundant decoding unit 1201-2-2. The point is similar.

  The normal-time communication control unit 1301-2-1-101 and the restoration-time communication control unit 1301-2-102 of the communication control unit 1301-2-100 are respectively a normal-time communication control unit 1101-1-101 of the second embodiment and a restoration. Compared with the time communication control unit 1101-1-102, the communication speed is calculated not by the packet reception / restoration status information but by the information from the packet reception unit 1301-2-1 and the redundant decoding unit 1201-2-2. Although different in the point of using information, the other points are the same, and thus detailed description thereof is omitted.

  The communication speed information transmission unit 1301-2-6 is information on the communication speed calculated by the normal time communication control unit 1301-2-2-101 or the restoration time communication control unit 1301-2-2-102 of the communication control unit 1301-2-100. Is transmitted to the data transmission device 1301-1.

Next, the overall operation of this embodiment will be described in detail with reference to FIG. 10, the flowchart of FIG. 11 showing the operation of the data transmission device 1301-1, and the flowchart of FIG. 12 showing the operation of the data reception device 1301-2. To do.
The communication speed information receiving unit 1301-1-13 of the data transmitting apparatus 1301-1 receives the communication speed information transmitted from the data receiving apparatus 1301-2 (step C110 in FIG. 11).

  The packet generator 1301-1-1 generates a packet according to the received communication speed information (step A106). The redundancy unit 1301-1-2 adds an error correction code to the generated packet (step A107). The packet transmission unit 1301-1-3 transmits the packet with the error correction code added to the data reception device 1301-2 (step A108).

The packet receiving unit 1301-2-1 of the data receiving device 1301-2 receives the packet transmitted from the data transmitting device 1301-1 (step A202 in FIG. 12).
Redundant decoding section 1301-2-2 restores the portion of the packet received by packet receiving section 1301-2-1 using the error correction code (step A203).

  The restoration status determining unit 1301-2-104 of the communication control unit 1301-2-100 determines the communication speed based on the reception status in the packet receiving unit 1301-2-1 and the restoration status in the redundant decoding unit 1301-2-2. It is selected whether the normal time communication control unit 1301-2-2-101 or the restoration time communication control 1301-2-2-102 is used as a control means (step C211). The selection operation of the restoration status determination unit 1301-2-2-104 has been described above and will not be described.

When the restoration status control unit 1301-2-2-102 is selected by the restoration status determination unit 1301-2104, the restoration time communication control unit 1301-2-2-102 calculates a communication speed at the time of packet restoration (step C212). ). When the normal time communication control unit 1301-2-2-101 is selected, the normal time communication control unit 1301-2-2-101 calculates the normal communication speed (step C213).
After calculating the communication speed, the communication speed information transmission unit 1301-2-6 transmits the communication speed information to the data transmission device 1301-1 (C214).

[Fifth embodiment]
Next, a fifth embodiment of the present invention will be described in detail with reference to the drawings. FIG. 13 is a block diagram showing a configuration of a communication system according to the fifth embodiment of the present invention. In this embodiment, when data is transmitted from the data transmission apparatus 2101-1 to the data reception apparatus 2101-7, the communication network 2101-2, the redundancy apparatus 2101-3, the communication network 2101-4, and the redundant decoding apparatus 2101 are used. -5 and communication network 2101-6 are assumed in order, and the process in this case will be described.

  Referring to FIG. 14, the communication system according to the present embodiment is directed to a data transmission apparatus 2101-1 that is an apparatus that transmits data, and to the data reception apparatus 2101-7 that receives the packet and makes the packet redundant by an error correction code. From the redundant transmission apparatus 2101-3 that receives the packet, restores the packet using an error correction code, and transmits the packet to the data reception apparatus 2101-7, and the data transmission apparatus 2101-1 And a data receiving device 2101-7 for receiving data.

  The data transmission apparatus 2101-1 includes a packet reception / restoration status information reception unit 2101-1-11, a communication control unit 2101-1-100, a packet generation unit 2101-1-1, and a packet transmission unit 2101-1. 3 is included. The communication control unit 2101-1-100 includes a restoration status determination unit 2101-1-104, a normal time communication control unit 2101-1-101, and a restoration time communication control unit 2101-1-102.

Packet reception / restoration status information reception unit 2101-1-11, restoration status determination unit 2101-1-104, normal time communication control unit 2101-1-101, restoration time communication control unit 2101-1-102, packet generation unit 2101 1-1 is a packet reception / restoration status information reception unit 1101-1-11, a restoration status determination unit 1101-1-104, a normal-time communication control unit 2101-1-101, and a restoration-time communication, respectively, according to the second embodiment. Since it is the same as that of the control part 2101-1-102 and the packet generation part 2101-1-1, it abbreviate | omits for details.
The packet transmission unit 2101-1-3 transmits the packet generated by the packet generation unit 2101-1-1 to the data reception device 2101-7.

The redundancy device 2101-3 includes a packet reception unit 2101-3-1, a redundancy unit 2101-3-2, and a packet transmission unit 2101-3-3.
The packet reception unit 2101-3-1 receives a packet from the data transmission device 2101-1.

The redundancy unit 2101-3-2 adds an error correction code to the packet received by the packet reception unit 2101-3-1. The packet redundancy method is not a problem as long as the packet can be restored by the redundant decoding device 2101-5. The packet made redundant by the redundancy unit 2101-3-2 may be different from the format of the packet received by the packet reception unit 2101-3-1, or may be compatible.
The packet transmission unit 2101-3-3 transmits the packet made redundant by the redundancy unit 2101-3-2 to the data reception device 2101-7.

The redundant decoding device 2101-5 includes a packet receiving unit 2101-5-1, a redundant decoding unit 2101-5-2, a packet transmitting unit 2101-5-3, and a packet restoration status information calculating unit 2101-5. 4 and a packet restoration status information adding unit 2101-5-5.
The packet reception unit 2101-5-1 receives the packet from the packet transmission unit 2101-3-3.

Redundant decoding section 2101-5-2 decodes the error correction code of the data received by packet reception section 2101-5-1 and restores the lost packet.
The packet restoration status information calculation unit 2101-5-4 calculates packet restoration status information from the restoration status in the redundant decoding unit 2101-5-2. The packet restoration status information is restoration information using an error correction code or packet reception information before restoration using an error correction code. Since the restoration information and the packet reception information by the error correction code have been described in detail in the description of the packet reception / restoration status information reception unit 1101-1-11 of the second embodiment, the details are omitted.

The packet restoration status information adding unit 2101-5-5 receives the packet restoration status information calculated by the packet restoration status information calculating unit 2101-5-4 and the packet received by the packet receiving unit 21-1-5-1 and the redundancy. The packet is added to the packet restored by the decoding unit 2101-5-2. As an addition method, there are a method of describing packet restoration status information as option information, and a method of generating a packet including the packet restoration status information and the restored packet as a data packet.
The packet transmission unit 2101-5-3 transmits the packet from the packet restoration status information addition unit 2101-5-5 to the data reception device 2101-7.

The data reception apparatus 2101-7 includes a packet reception unit 2101-7-1, a packet reception / restoration status information calculation unit 2101-7-2, and a packet reception / restoration status information transmission unit 2101-7-3.
The packet receiving unit 2101-7-1 receives the packet from the redundant decoding device 2101-5.

The packet reception / restoration status information calculation unit 2101-7-2 uses the reception status in the packet reception unit 2101-7-1 and the packet restoration status information added to the packet received by the packet reception unit 2101-7-1, Packet reception / restoration status information is calculated. Details of the packet reception / restoration status information have been described in detail in the description of the packet reception / restoration status information receiving unit 1101-1-11 of the second embodiment, and thus details thereof are omitted.
The packet reception / restoration status information transmission unit 2101-7-3 transmits the packet reception / restoration status information to the data transmission apparatus 2101-1.

Next, FIG. 14, the flowchart of FIG. 15 showing the operation of the data transmission apparatus 2101-1, the flowchart of FIG. 16 showing the operation of the redundancy apparatus 2101-3, and the operation of the redundancy decoding apparatus 2101-5 in FIG. The overall operation of this embodiment will be described in detail with reference to the flowchart and the flowchart of FIG. 18 showing the operation of the data receiving apparatus 2101-7.
The packet reception / restoration status information reception unit 2101-1-11 of the data transmission device 2101-1 receives the packet reception / restoration status information transmitted from the data reception device 2101-7 (step D102 in FIG. 15).

  Whether the restoration status determination unit 2101-1-104 of the communication control unit 2101-1-100 uses the normal time communication control unit 2101-1-101 as a means for controlling the communication speed based on the packet reception / restoration status information. Then, it is selected whether to use the restoration time communication control 2101-1-102 (step D103). The selection operation of the restoration situation determination unit 2101-1-1-104 has been described in the explanation of the restoration situation judgment unit 1101-1-1-104 of the second embodiment, and will be omitted.

  When the restoration-time communication control unit 2101-1-102 is selected by the restoration status determination unit 2101-1-104, the restoration-time communication control unit 2101-1-102 calculates a communication speed at the time of packet restoration (step D104). ). When the normal time communication control unit 2101-1-1-101 is selected, the normal time communication control unit 2101-1-1-101 calculates a normal communication speed (step D105).

  After calculating the communication speed, the packet generator 2101-1-1 generates a packet based on the calculated communication speed (step D106). The packet transmission unit 2101-1-3 transmits the generated packet to the data reception device 2101-7 (step D107).

The packet reception unit 2101-3-1 of the redundancy apparatus 2101-3 receives the packet transmitted from the data transmission apparatus 2101-1 (step D202 in FIG. 16).
The redundancy unit 2101-3-2 adds an error correction code to the packet from the packet reception unit 2101-3-1 (step D203).
The packet transmission unit 2101-3-3 transmits the packet with the error correction code added to the data reception device 2101-7 (step D204).

The packet receiving unit 2101-5-1 of the redundant decoding device 2101-5 receives the packet transmitted from the redundant device 2101-3 (step D302 in FIG. 17).
Redundant decoding section 2101-5-2 uses the error correction code to restore the portion of the packet received by packet reception section 2101-5-1 where the loss has occurred (step D 303).

The packet restoration status information calculation unit 2101-5-4 calculates packet restoration status information from the restoration status in the redundant decoding unit 2101-5-2 (step D304).
The packet restoration status information adding unit 2101-5-5 adds packet restoration status information to the packets from the packet receiving unit 2101-5-1 and the redundant decoding unit 2101-5-2 (step D305).
The packet transmitting unit 2101-5-3 transmits the packet from the packet restoration status information adding unit 2101-5-5 to the data receiving device 2101-7 (step D306).

The packet reception unit 2101-7-1 of the data reception device 2101-7 receives the packet transmitted from the redundant decoding device 2101-5 (step D402 in FIG. 18).
The packet reception / restoration status information calculation unit 2101-7-2 uses the reception status in the packet reception unit 2101-7-1 and the packet restoration status information added to the packet received by the packet reception unit 2101-7-1, Packet reception / restoration status information is calculated (step D403).

  The packet reception / restoration status information transmission unit 2101-7-3 transmits the packet reception / restoration status information calculated by the packet reception / restoration status information 2101-7-2 to the data transmission apparatus 2101-1 (step D404). .

  Next, the effect of the present embodiment will be described. In this embodiment, a redundancy apparatus 2101-3 that adds an error correction code to a packet and a redundant decoding apparatus 2101-5 that restores a packet using the error correction code include a data transmission apparatus 2101-1 and a data reception apparatus 2101. Since it is separated from -7, the redundancy device 2101-3 and the redundancy decoding device 2101-5 can be installed near a section where loss is likely to occur in the communication path such as a wireless section or a congestion section. According to the present embodiment, redundancy can be performed with redundancy suitable for each section by combining with the dynamic redundancy method. In the present embodiment, the data transmission apparatus 2101-1 and the redundancy apparatus 2101-3 have been described as separate apparatuses. These two devices may operate as one device similarly to the data transmission device 1101-1 in the second embodiment.

  In this embodiment, the packet reception status information and the packet restoration status information may be transmitted from the data reception device 2101-7 to the data transmission device 2101-1 in different packets.

[Sixth embodiment]
Next, a sixth embodiment of the present invention will be described in detail with reference to the drawings. FIG. 19 is a block diagram showing the configuration of the data transmission device, redundancy device, redundant decoding device, and data reception device of the communication system according to the sixth embodiment of the present invention. In this embodiment, instead of the data transmission device 2101-1, the redundancy device 2101-3, the redundancy decoding device 2101-5, and the data reception device 2101-7 in FIG. When data is sent from the data transmission device 2201-1 to the data reception device 2201-7 using the device 2201-3, redundant decoding device 2201-5, and data reception device 2201-7, the communication network 2101-2, redundancy The processing in this case will be described assuming that the communication device 2201-3, the communication network 2101-4, the redundant decoding device 2201-5, and the communication network 2101-6 are sequentially passed.

  Referring to FIG. 19, the communication system of the present embodiment is directed to a data transmission device 2201-1 that is a device for transmitting data and a data reception device 2201-7 that receives the packet and makes the packet redundant by an error correction code. From the redundancy transmission device 2201-3 for transmitting the data, the redundant decoding device 2201-5 for receiving the packet, restoring the packet by the error correction code, and transmitting the packet to the data reception device 2201-7, and the data transmission device 2201-1 And a data receiving device 2201-7 for receiving data.

  The data transmission device 2201-1 includes a packet reception / restoration status information reception unit 2201-1-11, a communication control unit 2201-1-100, a packet generation unit 2201-1-1, and a packet transmission unit 2201-1. 3 is included. The communication control unit 2201-1-1-100 includes a restoration status determination unit 2201-1-104, a normal time communication control unit 2201-1-101, and a restoration time communication control unit 2201-1-102.

  Packet reception / restoration status information reception unit 2201-1-1-11, communication control unit 2201-1-1-100, packet generation unit 2201-1-1-1, packet transmission unit 2201-1-3, restoration status determination unit 2201-1-104 The normal time communication control unit 2201-1-101 and the restoration time communication control unit 2201-1-102 are respectively a packet reception / restoration status information reception unit 2101-1-11 and a communication control unit 2101-1 of the fifth embodiment. −100, packet generation unit 2101-1-1, packet transmission unit 2101-1-3, restoration status determination unit 2101-1-104, normal time communication control unit 2101-1-101, restoration time communication control unit 2101-1 Detailed description is omitted because it is similar to −102.

  The redundancy device 2201-3 includes a packet reception unit 2201-3-1, a redundancy unit 2201-3-2, and a packet transmission unit 2201-3-3. The packet reception unit 2201-3-1, the redundancy unit 2201-3-2, and the packet transmission unit 2201-3-3 are respectively the packet reception unit 2101-3-1 and the redundancy unit 2101-3 of the fifth embodiment. 2. Since it is the same as the packet transmission unit 2101-3-3, a detailed description thereof will be omitted.

  The redundant decoding device 2201-5 includes a packet reception unit 2201-5-1, a redundant decoding unit 2201-5-2, a packet transmission unit 2201-5-3, and a packet restoration status information calculation unit 2201-5. 4 and a packet restoration status information transmission unit 2201-5-6. The packet receiving unit 2201-5-1, the redundant decoding unit 2201-5-2, and the packet restoration status information calculating unit 2201-5-4 are respectively the packet receiving unit 2101-5-1 and the redundant decoding in the fifth embodiment. This is the same as the unit 2101-5-2 and the packet restoration status information calculation unit 2101-5-4, and detailed description thereof will be omitted.

The packet transmission unit 2201-5-3 transmits the packet to which the error correction code is added by the redundant decoding unit 2201-5-2 to the data reception device 2201-7.
The packet restoration status information transmission unit 2201-5-6 transmits the packet restoration status information calculated by the packet restoration status information calculation unit 2201-5-4 to the data reception device 2201-7.

The data reception device 2201-7 includes a packet reception unit 2201-7-1, a packet restoration status information reception unit 2201-7-5, a packet reception / restoration status information calculation unit 2201-7-2, and a packet reception / restoration A status information transmission unit 2201-7-3.
The packet receiving unit 2201-7-1 receives the packet from the redundant decoding device 2201-5.
The packet restoration status information receiving unit 2201-7-5 receives the packet restoration status information from the redundant decoding device 2201-5.

The packet reception / restoration status information calculation unit 2201-7-2 receives the packet reception information received by the packet reception unit 2201-7-1 and the packet recovery status received by the packet recovery status information reception unit 2201-7-5. Packet reception / restoration status information is calculated from the information. Details of the packet reception / restoration status information have been described in detail in the description of the packet reception / restoration status information receiving unit 1101-1-11 of the second embodiment, and thus details thereof are omitted.
The packet reception / restoration status information transmission unit 2201-7-3 transmits the packet reception / restoration status information to the data transmission device 2201-1.

Next, the overall operation of this embodiment will be described in detail using FIG. 19, the flowchart of FIG. 20 showing the operation of the redundant decoding device 2201-5, and the flowchart of FIG. 21 showing the operation of the data receiving device 2201-7. explain.
Since the operations of the data transmission device 2201-1 and the redundancy device 2201-3 are the same as the operations of the data transmission device 2101-1 and the redundancy device 2101-3 of the fifth embodiment, detailed description thereof is omitted.

The operation of the redundant decoding device 2201-5 will be described in detail. The packet receiving unit 2201-5-1 receives the packet from the redundant decoding device 2201-3 (step D302 in FIG. 20).
Redundant decoding section 2201-5-2 restores the portion of the packet received by packet receiving section 2201-5-1 using the error correction code (step D303).

The packet restoration status information calculation unit 2201-5-4 calculates packet restoration status information from the restoration status in the redundant decoding unit 2201-5-2 (step D304).
The packet restoration status information transmission unit 2201-5-6 transmits the packet restoration status information to the data reception device 2201-7 (step E305). The process of step E305 may be performed any time after step D303.
The packet transmission unit 2201-5-3 transmits the packet from the redundant decoding unit 2201-5-2 to the data reception device 2201-7 (step D306).

The operation of the data receiving device 2201-7 will be described in detail. The packet receiving unit 2201-7-1 receives the packet from the redundant decoding device 2201-5 (step D402 in FIG. 21).
The packet restoration status information receiving unit 2201-7-5 receives the packet restoration information from the redundant decoding device 2201-5 (step E310).

The packet reception / restoration status information calculation unit 2201-7-2 receives the packet from the packet restoration status information received by the packet restoration status information reception unit 2201-7-5 and the reception status of the packet reception unit 2201-7-1. -Restore status information is calculated (step E403).
The packet reception / restoration status information transmission unit 2201-7-3 transmits the packet reception / restoration status information calculated by the packet reception / restoration status information 2101-7-2 to the data transmission device 2201-1 (step D404). .

In the present embodiment, the data transmission device 2201-1 and the redundancy device 2201-3 have been described as separate devices. These two devices may operate as one device similarly to the data transmission device 1101-1 in the second embodiment.
In this embodiment, the packet reception status information and the packet restoration status information may be transmitted from the data reception device 2201-7 to the data transmission device 2201-1 in different packets.

[Seventh embodiment]
Next, a seventh embodiment of the present invention will be described in detail with reference to the drawings. FIG. 22 is a block diagram showing the configuration of the data transmitting apparatus, redundancy apparatus, redundant decoding apparatus, and data receiving apparatus of the communication system according to the seventh embodiment of the present invention. In this embodiment, instead of the data transmission device 2101-1, the redundancy device 2101-3, the redundant decoding device 2101-5, and the data reception device 2101-7 in FIG. When data is transmitted from the data transmission device 2301-1 to the data reception device 2301-7 using the device 2301-3, the redundant decoding device 2301-5, and the data reception device 2301-7, the communication network 2101-2, redundancy The processing in this case will be described assuming that the communication device 2301-3, the communication network 2101-4, the redundant decoding device 2301-5, and the communication network 2101-6 are sequentially passed.

  Referring to FIG. 22, the communication system of the present embodiment is directed to a data transmission device 2301-1 that is a device that transmits data, and to a data reception device 2301-7 that receives the packet and makes the packet redundant by an error correction code. From the redundant transmission device 2301-3 that receives the packet, restores the packet using an error correction code, and transmits the packet to the data reception device 2301-7, and the data transmission device 2301-1 And a data receiving device 2301-7 for receiving data.

  The data transmission device 2301-1 includes a packet reception information reception unit 2301-1-12, a packet restoration status information reception unit 2301-1-13, a packet reception / restoration status information calculation unit 2301-1-14, and communication control. Unit 2301-1-1-100, packet generation unit 2301-1-1, and packet transmission unit 2301-1-3. The communication control unit 2301-1-1-100 includes a restoration status determination unit 2301-1-104, a normal time communication control unit 2301-1-101, and a restoration time communication control unit 2301-1-102.

  The communication control unit 2301-1-1-100, the packet generation unit 2301-1-1, the packet transmission unit 2301-1-1-3, the normal time communication control unit 2301-1-101, and the restoration time communication control unit 2301-1-1-102, Communication control unit 2101-1-100, packet generation unit 2101-1-1, packet transmission unit 2101-1-3, normal time communication control unit 2101-1-1-101, restoration time communication control unit 2101 of the fifth embodiment, respectively. Since it is the same as -1-102, detailed description is omitted.

The packet reception information reception unit 2301-1-12, the packet restoration status information reception unit 2301-1-13, and the packet reception / restoration status information calculation unit 2301-1-14 constitute a restoration status information acquisition unit.
The packet reception information reception unit 2301-1-12 receives packet reception information from the data reception device 2301-7. The packet reception information is packet reception information in the packet reception unit 2301-7-1 of the data reception device 2301-7. The packet restoration status information receiving unit 2301-1-13 receives the packet restoration status information from the redundant decoding device 2301-5.

The packet reception / restoration status information calculation unit 2301-1-14 receives the packet reception information received by the packet reception information reception unit 2301-1-12 and the packet restoration status information received by the packet recovery status information reception unit 2301-1-13. Then, packet reception / restoration status information is calculated.
The restoration status determination unit 2301-1-1-104 uses the normal-time communication control unit 2301-1-101 or the restoration-time communication control 2301-1, as compared with the restoration status determination unit 1101-1-104 of the second embodiment. The packet reception / restoration status information calculation unit 2301-1-14 uses the packet reception / restoration status information calculated in the packet reception / restoration status information calculation unit 2301-1-14. To do.

  The redundancy device 2301-3 includes a packet reception unit 2301-3-1, a redundancy unit 2301-3-2, and a packet transmission unit 2301-3-3. The packet reception unit 2301-3-1, the redundancy unit 2301-3-2, and the packet transmission unit 2301-3-3 are respectively the packet reception unit 2101-3-1 and the redundancy unit 2101-3 of the fifth embodiment. 2. Since it is the same as the packet transmission unit 2101-3-3, a detailed description thereof will be omitted.

The redundant decoding device 2301-5 includes a packet reception unit 2301-5-1, a redundant decoding unit 2301-5-2, a packet transmission unit 2301-5-3, and a packet restoration status information calculation unit 2301-5. 4 and a packet restoration status information transmission unit 2301-5-7. The packet receiving unit 2301-5-1, the redundant decoding unit 2301-5-2, the packet transmitting unit 2301-5-3, and the packet restoration status information calculating unit 2301-5-4 are each a packet receiving unit of the fifth embodiment. Since 2101-5-1, redundant decoding unit 2101-5-2, packet transmission unit 2101-5-3, and packet restoration status information calculation unit 2101-5-4, detailed description is omitted.
The packet restoration status information transmission unit 2301-5-7 transmits the packet restoration status information to the data transmission device 2301-1.

The data reception device 2301-7 includes a packet reception unit 2301-7-1, a packet reception information calculation unit 2301-7-6, and a packet reception information transmission unit 2301-7-7.
The packet receiving unit 2301-7-1 receives the packet from the redundant decoding device 2301-5.

The packet reception information calculation unit 2301-7-6 calculates the packet reception information from the reception status in the packet reception unit 2301-7-1.
The packet reception information transmission unit 2301-7-7 transmits the packet reception information calculated by the packet reception information calculation unit 2301-7-6 to the data transmission device 2301-1.

  Next, FIG. 22, the flowchart of FIG. 23 showing the operation of the data transmitting apparatus 2301-1, the flowchart of FIG. 24 showing the operation of the redundant decoding apparatus 2301-5, and the operation of the data receiving apparatus 2301-7 of FIG. The overall operation of this embodiment will be described in detail with reference to a flowchart.

The operation of the data transmission device 2301-1 will be described in detail. The packet restoration status information receiving unit 2301-1-13 receives the packet restoration status information from the redundant decoding device 2301-5 (step F110 in FIG. 23).
The packet reception information receiving unit 2301-1-12 receives the packet reception information from the data reception device 2301-7 (step F102).

  The packet reception / restoration status information calculation unit 2301-1-14 receives the packet reception information received by the packet reception information reception unit 2301-1-12 and the packet restoration status information received by the packet recovery status information reception unit 2301-1-13. Packet reception / restoration status information is calculated from the above (step F111).

  Restoration status determination unit 2301-1-104, restoration-time communication control unit 2301-1-102, normal-time communication control unit 2301-1-101, and packet generation unit 2301-1-1 shown in steps D103 to D107 of FIG. The operation of the packet transmission unit 2301-1-3 is the same as the restoration status determination unit 2101-1-104, the restoration-time communication control unit 2101-1-102, and the normal-time communication control unit 2101-1-101 according to the fifth embodiment. The operations of the packet generator 2101-1-1 and the packet transmitter 2101-1-3 are the same as those of the packet generator 2101-1-2, and the description thereof is omitted.

  Since the operation of the redundancy device 2301-3 is the same as that of the redundancy device 2101-3 of the fifth embodiment, the description thereof is omitted.

The operation of the redundant decoding device 2301-5 will be described in detail. The packet receiving unit 2301-5-1, the redundant decoding unit 2301-5-2, the packet restoration status information calculating unit 2301-5-4, and the packet transmitting unit 2301-5 shown in steps D302 to D304 and D306 in FIG. 3 operations are the packet receiving unit 2201-5-1, the redundant decoding unit 2201-5-2, the packet restoration status information calculating unit 2201-5-4, and the packet transmitting unit 2201-5-3 of the sixth embodiment, respectively. Since the operation is the same as that in FIG.
The packet restoration status information transmission unit 2201-5-7 transmits the packet restoration status information to the data transmission device 2301-1 (step F305 in FIG. 24).

The operation of the data receiving device 2301-7 will be described in detail. The packet receiving unit 2301-7-1 receives the packet from the redundant decoding device 2301-5 (step D402 in FIG. 24).
The packet reception information calculation unit 2301-7-6 calculates the packet reception information from the reception status in the packet reception unit 2301-7-1 (step F403).
The packet reception information transmission unit 2301-7-7 transmits the packet reception information to the data transmission device 2301-1 (step F404).

  In the present embodiment, the data transmission device 2301-1 and the redundancy device 2301-3 have been described as separate devices. These two devices may operate as one device. In this case, the packet transmission unit 2301-1-3- and the packet reception unit 2301-3-1 are eliminated, and the packet generation unit 2301-1-1 and the redundancy unit 2301-3-2 are directly connected.

[Eighth embodiment]
Next, an eighth embodiment of the present invention will be described in detail. In this embodiment, statistical information is handled in the same manner as the third embodiment in the configuration of the fifth embodiment.
Specifically, the packet reception / restoration status information reception unit 2101-1-11, the packet reception / restoration status information calculation unit 2101-7-2, the packet reception / restoration status information transmission unit 2101-7- of the fifth embodiment. 3, the restoration status determination unit 2101-1-104, the normal time communication control unit 2101-1-101, and the restoration time communication control unit 2101-1-102, respectively, the statistical information receiving unit 1201-1-12 of the third embodiment. , Packet reception / restoration statistical information calculation unit 1201-2-5, statistical information transmission unit 1201-2-6, restoration status determination unit 1201-1-104, normal time communication control unit 1201-1-101, restoration time communication control What is necessary is just to give the same function as the part 1201-1-1-102. Thereby, packet reception / restoration statistical information can be used instead of packet reception / restoration status information.

  The handling of the packet reception / restoration statistical information has been described in detail in the third embodiment, and the details are omitted. In this embodiment, the packet reception statistical information and the packet restoration statistical information may be transmitted from the data receiving apparatus to the data transmitting apparatus in different packets.

  Also, the packet restoration status information calculation unit 2101-5-4 and the packet restoration status information addition unit 2101-5-5 of the fifth embodiment are changed to handle packet restoration statistical information instead of the packet restoration status information. Also good. The packet restoration statistical information is restoration statistical information by an error correction code or packet reception statistical information before restoration by an error correction code. Since the restoration statistical information by the error correction code and the packet reception statistical information before the restoration by the error correction code are described in detail in the third embodiment, the details are omitted.

[Ninth embodiment]
Next, a ninth embodiment of the present invention will be described in detail. In this embodiment, statistical information is handled in the same manner as in the third embodiment in the configuration of the sixth embodiment.
Specifically, the packet reception / restoration status information reception unit 2201-1-11, the packet reception / restoration status information calculation unit 2201-7-2, and the packet reception / restoration status information transmission unit 2201-7- of the sixth embodiment. 3, the restoration status determination unit 2201-1-1-104, the normal time communication control unit 2201-1-101, and the restoration time communication control unit 2201-1-102, respectively, and the statistical information receiving unit 1201-1-12 of the third embodiment. , Packet reception / restoration statistical information calculation unit 1201-2-5, statistical information transmission unit 1201-2-6, restoration status determination unit 1201-1-104, normal time communication control unit 1201-1-101, restoration time communication control What is necessary is just to give the same function as the part 1201-1-1-102. Thereby, packet reception / restoration statistical information can be used instead of packet reception / restoration status information.

In this embodiment, the packet reception statistical information and the packet restoration statistical information may be transmitted from the data receiving apparatus to the data transmitting apparatus in different packets.
Further, the packet restoration status information calculation unit 2201-5-4 and the packet restoration status information transmission unit 2201-5-6 of the sixth embodiment are changed to handle packet restoration statistical information instead of the packet restoration status information. Also good.

[Tenth embodiment]
Next, a tenth embodiment of the present invention will be described in detail. In the present embodiment, statistical information is handled in the same manner as the third embodiment in the configuration of the seventh embodiment.
Specifically, instead of the packet reception information, the packet reception information calculation unit 2301-7-6, the packet reception information transmission unit 2301-7-7, and the packet reception information reception unit 2301-1-12 of the seventh embodiment Handle reception statistics information. Further, in the packet restoration status information calculation unit 2301-5-4, the packet restoration status information transmission unit 2301-5-7, and the packet restoration status information reception unit 2301-1-1-13, packet restoration status statistics are used instead of the packet restoration status information. Handle information. The packet restoration status statistical information is restoration statistical information by an error correction code or packet reception statistical information before restoration by an error correction code.

  In this embodiment, the packet reception / restoration status information calculating unit 2301-1-14 calculates packet reception / restoration statistical information by combining the packet reception statistical information and the packet recovery status statistical information. In the restoration status determination unit 2301-1-1-104, the normal time communication control unit 2301-1-101, and the restoration time communication control unit 2301-1-1-102, the restoration status determination unit 1201-1-104 of the third embodiment, Communication control is performed based on the packet reception / restoration statistical information in the same manner as the normal time communication control unit 1201-1-101 and the restoration time communication control unit 1201-1-102. Since packet reception / restoration statistical information, packet reception statistical information, restoration statistical information by error correction code, and packet reception statistical information before restoration by error correction code are described in detail in the third embodiment, the details are omitted.

  In the second to fourth embodiments, the case of one-to-one data transmission device and data reception device has been described. However, in the present invention, even when there are a plurality of data transmission devices and data reception devices, there is a plurality. Well, there are no restrictions on the number of devices or the number of combinations. Further, the elements constituting the data transmitting apparatus and the elements constituting the data receiving apparatus can be put in the same apparatus.

  In the fifth to tenth embodiments, the case where there is one data transmission device, one redundancy device, one redundancy decoding device, and one data reception device has been described. However, the present invention is not limited to any one or more. The present invention can be implemented even when there are a plurality of devices, and is not limited by the number of devices or the number of combinations. In addition, an element constituting the data transmitting apparatus and an element constituting the data receiving apparatus, an element constituting the redundancy apparatus, and an element constituting the redundant decoding apparatus can be included in the same apparatus.

  In all the embodiments, the case where there is one each of the normal time communication control unit and the restoration time communication control unit has been described. However, even if at least one of the normal time communication control unit and the restoration time communication control unit is plural, Good. In this case, the restoration status determination unit may select either the normal time communication control unit or the restoration time communication control unit according to the restoration status of the error correction code.

  Further, in all the embodiments, the data transmission device can operate as a relay that converts any protocol including the protocol targeted by the present invention to the protocol targeted by the present invention, and the data receiving device is the present invention. It is possible to operate as a repeater that converts the protocol targeted by the protocol to any protocol including the protocol targeted by the present invention.

[Eleventh embodiment]
Next, an eleventh embodiment of the present invention will be described. In this embodiment, the communication protocol between the data transmission apparatus and the data reception apparatus in the second embodiment and the fifth to seventh embodiments is TCP (document “W. Richard Stevens,“ TCP / IP Illustrated: The Protocols ”, Addison-Wesley, 1994”).

  The normal time communication control unit of the present embodiment uses TCP congestion control. Specifically, the congestion window is controlled on an ACK (ACKnowledgment) basis, and the congestion window is lowered when a duplicate ACK with the same ACK sequence number occurs. Normally, a duplicate ACK is made when three identical ACK sequence numbers continue.

  When TCP-Reno is used as TCP congestion window control, when duplicate ACK occurs, the congestion window is lowered to half after retransmission control. As a method of distinguishing the additional part of redundancy by the error correction code from the data part, a method of defining normal packets and redundant packets as TCP options and making them compatible with existing TCP, or normal packets and redundant packets There is a method of encapsulating with a packet having a flag for distinguishing. The packet reception status information can be notified by TCP ACK. The packet restoration status information can be notified by newly defining an ACK option.

[Twelfth embodiment]
Next, a twelfth embodiment of the present invention will be described. In this embodiment, in the second embodiment and the fifth to seventh embodiments, as a protocol between the data transmitting apparatus and the data receiving apparatus, DCCP (documents “E. Kohler, J. Handley, S. Floyd,“ RFC4340: Datagram Congestion Control Protocol (DCCP) ”, see IETF, Mar. 2006”).

  The normal-time communication control unit of the present embodiment is a CCCP2 of DDCP that performs congestion window control based on ACK (ACKnowledgment) (references “S.Floyd, E. Kohler,“ RFC4341: Profile for Datagram Congestion Control Protocol (DCCP) Congestion Control ID 2: TCP-like Congestion Control ”, IETF, Mar. 2006”). This congestion window control is the same AIMD (Additive-Increase and Multiplicative-Decrease) type control as TCP-Reno.

  As a method of distinguishing the additional part of redundancy by the error correction code and the data part, a method of defining a normal packet and a redundant packet as an option of the DCCP and making it compatible with an existing DCCP, a normal packet and a redundant packet, There is a method of encapsulating with a packet having a flag for distinguishing. The packet reception status information can be notified by DCCP ACK. The packet restoration status information can be notified by newly defining an ACK option.

[Thirteenth embodiment]
Next, a thirteenth embodiment of the present invention will be described. This embodiment uses a procedure based on DCCP as a communication protocol between the data transmitting device and the data receiving device in the third embodiment and the eighth to tenth embodiments.
The normal-time communication control unit according to the present embodiment performs DDCP CCID3 (references “S.Floyd, E. Kohler, J. Padhye,” “RFC4342: Profile for Datagram Congestion Control Protocol (DCCP) Congestion Control ID 3: TCP-Friendly Rate Control (TFRC) ”, IETF, Mar. 2006”).

  As a method for distinguishing the additional portion of redundancy by the error correction code from the data portion, a method for defining normal packets and redundant packets as DCCP options and making them compatible with existing DCCP, or normal packets and redundant packets There is a method of encapsulating with a packet having a flag for distinguishing. The packet reception statistical information can be notified by the DCCP ACK option. The packet restoration statistical information can be notified by newly defining an ACK option.

  The present invention has packet delimiters such as packets, segments, and cells to which error correction codes can be added, and can be implemented by using a protocol that controls the communication speed via a communication network such as a network or a data bus. It is. Data may be converted into digital data, and the type of content such as audio and video is not limited.

  The data transmission device, redundancy device, redundant decoding device, and data reception device of the first to thirteenth embodiments are respectively a computer having a CPU, a storage device, and an external interface, and hardware thereof. It can be realized by a program for controlling resources. In these computers, a communication program for realizing the communication method of the present invention is provided in a state of being recorded on a recording medium such as a flexible disk, a CD-ROM, a DVD-ROM, or a memory card. The CPU writes the program read from the recording medium to the storage device, and executes the processes described in the first to thirteenth embodiments according to the program.

Although the present invention has been described with reference to the above-described embodiment, the present invention is not limited to the above-described embodiment. The configuration and details of the present invention may be used by appropriately combining the above-described embodiments, and may be modified as appropriate within the scope of the claims of the present invention.
This application claims the priority on the basis of Japanese application Japanese Patent Application No. 2007-280128 for which it applied on October 29, 2007, and takes in those the indications of all here.

  The present invention can be applied to applications such as a communication system, a data transmission device, a data reception device, and a communication program that perform communication using packets such as IP.

Claims (32)

Restoration status information acquisition means for acquiring information on the restoration status of the packet by an error correction code added to a packet transmitted and received via a communication network;
Restoration status judging means for selecting whether to perform communication control processing at normal time or to perform communication control processing at the time of restoring packet loss due to congestion according to the status of packet restoration by the error correction code;
When it is selected to perform the normal communication control processing, a normal communication control means for performing communication speed control using congestion information;
And a restoration-time communication control means for reducing the communication speed or reducing the increase rate of the communication speed compared to the normal time when the communication control processing at the time of restoration is selected. Communications system. The communication system according to claim 1, wherein
The restoration status judging means selects to perform the normal communication control process when judging that the packet can be restored by the error correction code, and when judging that the packet cannot be restored, A communication system characterized by selecting to perform communication control processing. The communication system according to claim 1, wherein
The restoration communication control means calculates a communication speed or an increase in communication speed according to the redundancy of the error correction code. The communication system according to claim 1, wherein
The communication control means at the time of restoration reduces the communication speed or decreases the increase rate of the communication speed according to the redundancy of the error correction code. The communication system according to claim 1, wherein
The restoration status information acquisition unit and the restoration status determination unit use the reception information after restoration by the error correction code and the restoration information by the error correction code as the restoration status information of the packet by the error correction code. system. The communication system according to claim 5, wherein
The restoration status information acquisition unit and the restoration status determination unit use at least one of information indicating a reception location and information indicating a loss location as the reception information, and error correction as the recovery information by the error correction code. A communication system using at least one of a flag indicating whether or not a packet has been restored by a code, information on a restoration location, the number of restorations, and a restoration rate. The communication system according to claim 1, wherein
The communication system characterized in that the restoration status information acquisition means and the restoration status judgment means use reception information before and after restoration by an error correction code as restoration status information of a packet by the error correction code. The communication system according to claim 7,
The restoration status information acquisition unit and the restoration status determination unit use one or more of information indicating a reception location and information indicating a loss location as the reception information. The communication system according to claim 1, wherein
The restoration status information acquisition unit and the restoration status determination unit use statistical information of a restoration status of a packet by an error correction code as restoration status information of a packet by the error correction code. The communication system according to claim 9,
The restoration status information acquisition unit and the restoration status determination unit use reception statistical information after restoration using an error correction code and restoration statistical information using an error correction code as statistical information on the restoration status of a packet using the error correction code. A featured communication system. The communication system according to claim 10,
The restoration status information acquisition unit and the restoration status determination unit include, as the reception statistical information, any one of the number of transmission packets and the number of reception packets, transmission / reception packet rate, loss number, loss size, and loss rate at a certain time. Using the above, as the restoration statistical information, any one or more of a flag indicating whether or not a packet has been restored by an error correction code within a predetermined time, the number of restorations within a predetermined time, and a restoration rate within a predetermined time are used. A communication system characterized by the above. The communication system according to claim 9,
The restoration status information acquisition unit and the restoration status determination unit use reception statistical information before and after restoration by an error correction code as statistical information of a restoration status of a packet by the error correction code. The communication system according to claim 12,
The restoration status information acquisition unit and the restoration status determination unit include, as the reception statistical information, any one of the number of transmission packets and the number of reception packets, transmission / reception packet rate, loss number, loss size, and loss rate at a certain time. A communication system characterized by using the above. Packet transmitting means for receiving a packet via a communication network and correcting a packet error using an error correction code, a packet transmission means for transmitting the packet with the error correction code added thereto;
A restoration status information obtaining unit for obtaining information on a restoration status of a packet by an error correction code in the data receiving device;
Restoration status judging means for selecting whether to perform communication control processing at normal time or to perform communication control processing at the time of restoring packet loss due to congestion according to the status of packet restoration by the error correction code;
When it is selected to perform the normal communication control processing, a normal communication control means for performing communication speed control using congestion information;
And a restoration-time communication control means for reducing the communication speed or reducing the increase rate of the communication speed compared to the normal time when the communication control processing at the time of restoration is selected. Data transmission device. The data transmission device according to claim 14, wherein
The restoration status judging means selects to perform the normal communication control process when judging that the packet can be restored by the error correction code, and when judging that the packet cannot be restored, A data transmission apparatus that selects to perform communication control processing. The data transmission device according to claim 14, wherein
The restoration-time communication control means calculates a communication speed or an increase width of the communication speed in accordance with the redundancy of the error correction code. The data transmission device according to claim 14, wherein
The restoration-time communication control means reduces the communication speed or decreases the increase rate of the communication speed according to the redundancy of the error correction code. The data transmission device according to claim 14, wherein
The restoration status information acquisition unit and the restoration status judgment unit use the received information after restoration by the error correction code and the restoration information by the error correction code as the restoration status information of the packet by the error correction code. Transmitter device. The data transmission device according to claim 18, wherein
The restoration status information acquisition unit and the restoration status determination unit use at least one of information indicating a reception location and information indicating a loss location as the reception information, and error correction as the recovery information by the error correction code. A data transmission apparatus using at least one of a flag indicating whether or not a packet has been restored by a code, information on a restoration location, the number of restorations, and a restoration rate. The data transmission device according to claim 14, wherein
The restoration status information acquisition unit and the restoration status determination unit use reception information before and after restoration by an error correction code as restoration status information of a packet by the error correction code. The data transmission device according to claim 20,
The restoration status information acquisition means and the restoration status determination means use one or more of information indicating a reception location and information indicating a loss location as the reception information. The data transmission device according to claim 14, wherein
The restoration status information acquisition unit and the restoration status determination unit use statistical information of a restoration status of a packet by an error correction code as restoration status information of a packet by the error correction code. The data transmission device according to claim 22,
The restoration status information acquisition unit and the restoration status determination unit use reception statistical information after restoration using an error correction code and restoration statistical information using an error correction code as statistical information on the restoration status of a packet using the error correction code. A data transmission device. The data transmission device according to claim 23,
The restoration status information acquisition unit and the restoration status determination unit include, as the reception statistical information, any one of the number of transmission packets and the number of reception packets, transmission / reception packet rate, loss number, loss size, and loss rate at a certain time. Using the above, as the restoration statistical information, any one or more of a flag indicating whether or not a packet has been restored by an error correction code within a predetermined time, the number of restorations within a predetermined time, and a restoration rate within a predetermined time are used. A data transmission device characterized by the above. The data transmission device according to claim 22,
The restoration status information acquisition unit and the restoration status determination unit use reception statistical information before and after restoration by an error correction code as statistical information of a restoration status of a packet by the error correction code. The data transmission device according to claim 25,
The restoration status information acquisition unit and the restoration status determination unit include, as the reception statistical information, any one of the number of transmission packets and the number of reception packets, transmission / reception packet rate, loss number, loss size, and loss rate at a certain time. A data transmission apparatus using the above. A packet receiving means for receiving the packet via a communication network from a data transmitting apparatus that transmits a packet with an error correction code added thereto;
Redundant decoding means for correcting an error of the packet received by the packet receiving means using the error correction code;
A restoration status judging means for selecting whether to perform a normal communication control process or a communication control process when restoring a packet loss due to congestion according to the restoration status of the packet by the error correction code in the redundant decoding means;
When it is selected to perform the normal communication control processing, a normal communication control means for performing communication speed control using congestion information;
And a restoration-time communication control means for reducing the communication speed or reducing the increase rate of the communication speed compared to the normal time when the communication control processing at the time of restoration is selected. Data receiving device. A packet transmission means for transmitting the packet to the redundancy device for adding an error correction code to the packet received via the communication network;
Obtains information on the restoration status of the packet by the error correction code in the redundant decoding device that corrects the error of the packet received from the redundancy device using the error correction code and transmits the corrected packet to the data reception device. Restoring status information acquisition means to perform,
Restoration status judging means for selecting whether to perform communication control processing at normal time or to perform communication control processing at the time of restoring packet loss due to congestion according to the status of packet restoration by the error correction code;
When it is selected to perform the normal communication control processing, a normal communication control means for performing communication speed control using congestion information;
And a restoration-time communication control means for reducing the communication speed or reducing the increase rate of the communication speed compared to the normal time when the communication control processing at the time of restoration is selected. Data transmission device. The data transmission device according to claim 28, wherein
The restoration status information acquisition unit and the restoration status determination unit use statistical information of a restoration status of a packet by an error correction code as restoration status information of a packet by the error correction code. A restoration status information acquisition step of acquiring information on the restoration status of the packet by an error correction code added to a packet transmitted and received via a communication network;
A restoration status determination step for selecting whether to perform communication control processing at normal time or to perform communication control processing at the time of restoration of packet loss due to congestion according to the restoration status of the packet by the error correction code;
A normal communication control step for performing communication speed control using congestion information when the normal communication control process is selected;
A restoration communication control step for reducing the communication speed or reducing the increase in the communication speed compared to the normal time when the communication control process at the time of restoration is selected. Communication method. A packet transmission step of transmitting a packet with the error correction code to a data receiving device that receives the packet via a communication network and corrects the error of the packet using an error correction code;
A restoration status information acquisition step of acquiring information on the restoration status of the packet by the error correction code;
A restoration status determination step for selecting whether to perform communication control processing at normal time or to perform communication control processing at the time of restoration of packet loss due to congestion according to the restoration status of the packet by the error correction code;
A normal communication control step for performing communication speed control using congestion information when the normal communication control process is selected;
When the communication control process at the time of restoration is selected, causing the computer to execute a communication control step at the time of restoration that reduces the communication speed or reduces the increase rate of the communication speed compared to the normal time. A communication program for a data transmission device. A packet receiving step of receiving the packet from the data transmission device that transmits the packet with the error correction code added thereto via a communication network;
A redundant decoding step of correcting an error of the packet received in the packet reception step using the error correction code;
A restoration status determination step for selecting whether to perform normal communication control processing according to the restoration status of packets by the error correction code in the redundant decoding step or to perform communication control processing at the time of restoration of packet loss due to congestion,
A normal communication control step for performing communication speed control using congestion information when the normal communication control process is selected;
When the communication control process at the time of restoration is selected, causing the computer to execute a communication control step at the time of restoration that reduces the communication speed or decreases the increase rate of the communication speed than the normal time. A communication program for a data receiving apparatus .

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