JP6673604B2 - Log data transfer method and log data transfer system - Google Patents

Description

  The present invention relates to a log data transfer method and a log data transfer system for preventing loss of log data when transferring log data generated by one computer to another computer over a network, for example. is there.

  2. Description of the Related Art FEC (Forward Error Correction) is known as a technique for recovering data on the receiving side without requesting the transmitting side to retransmit a packet loss that occurs when data is transferred using IP packets. In FEC, data with a redundant code added in advance is transmitted in anticipation of occurrence of an error, and data is restored at the receiving side. The transmitting side adds an error correction code to the original data according to a certain rule. Send An advantage of FEC is that high throughput can be achieved on average by preventing data retransmission. However, there is a problem that, for example, a start-up delay in streaming reproduction on the receiving side, that is, a time from receiving a source packet to start reproduction to outputting video or audio for the first time is increased.

  To solve the problem of the start-up delay, for example, in a packet transmission system according to Patent Document 1, a packet transmitting device adds a time stamp to FEC data and notifies a packet receiving device of a packet recovery timing. I have. This makes it possible to suppress the start-up delay by coordinating the timing of the FEC restoration processing with the decoding processing of the video signal and the audio signal.

JP 2013-192031 A

  In an information transmission system using a one-way communication device, the one-way communication device controls the communication data to flow from the transmitting side to the receiving side in only one direction. In such an information transmission system, at the time of data transmission, a response cannot be returned from the data receiving side to the data transmitting side, so that delivery confirmation cannot be performed and data reachability is not guaranteed.

  Therefore, in such an information transmission system, when data, such as log data, which occurs intermittently and has no regularity in data generation timing or content, is transferred via a one-way communication device, reception is difficult. There is a problem that it is difficult to detect the loss of log data by looking at the contents on the side.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and enables loss of transferred log data to be detected and restoration of lost log data to be possible. It is an object of the present invention to provide a log data transfer method and a log data transfer system that improve reliability at the time.

In order to solve the above-mentioned problem, the log data transfer method according to the present invention adds a log packet serial number to log data on the transmission side to generate a log packet, and transmits M log data consecutively. A forward error correction packet is generated by adding the M log packet serial numbers to the forward error correction data generated by calculating exclusive OR as a set, and the log packet and the forward error correction packet are transmitted. Then, on the receiving side, when it is detected that any of the log packet serial numbers of the forward error correction packet is missing, the received set of log data and the forward error correction data And restores the log packet by calculating an exclusive OR of the log data, and extracts log data from the restored log packet.

  In addition, the log data transfer system according to the present invention is a log packet generation unit that generates a log packet in which a log packet serial number is added to log data, and calculates an exclusive OR using a set of M consecutive log data. A forward error correction packet generation unit that generates a forward error correction packet obtained by adding the M log packet serial numbers to the forward error correction data generated by the above, and a packet transmission unit that transmits the log packet and the forward error correction packet. A log transmitting side computer, a packet receiving unit that receives the log packet and the forward error correction packet, and identifies whether the log packet is the forward error correction packet and the log packet of the forward error correction packet A received packet identification unit for detecting the presence or absence of any of the serial numbers; A log packet restoring unit configured to calculate an exclusive OR of the received set of log data and the forward error correction data to restore the log packet when a loss occurs in any of the serial numbers; A log receiving computer having a log packet processing unit for extracting log data from the restored log packet.

  According to the log data transfer method and the log data transfer system of the present invention, a serial number for uniquely identifying log data to be transmitted is added, and a data redundancy method by FEC is used. Detecting loss of log data based on the serial number of log data and restoring the lost log data using FEC data has the effect of improving the reliability of log data transfer.

FIG. 1 is a configuration diagram illustrating an outline of a log data transfer system according to a first embodiment. 9 is a flowchart illustrating a transmission processing procedure in the log transmission-side computer according to the first embodiment. FIG. 3 is a log packet format diagram showing a configuration of a log packet according to the first embodiment. FIG. 4 is a diagram for describing a method of generating FEC data according to the first embodiment. FIG. 3 is an FEC packet format diagram showing a configuration of an FEC packet according to the first embodiment. 9 is a flowchart illustrating a reception processing procedure in the log receiving-side computer according to the first embodiment. FIG. 5 is a diagram for describing a data restoration method according to the first embodiment. 17 is a flowchart illustrating a transmission processing procedure of the log transmission-side computer according to the second embodiment. FIG. 13 is a diagram for describing a method of generating FEC data according to the second embodiment. FIG. 13 is a configuration diagram illustrating an outline of a log data transfer system according to a third embodiment. 15 is a flowchart illustrating a transmission processing procedure in the log transmission-side computer according to the third embodiment. FIG. 13 is a dummy packet format diagram showing a configuration of a dummy packet according to the third embodiment. 15 is a flowchart illustrating a reception processing procedure in the log receiving-side computer according to the third embodiment. FIG. 14 is a configuration diagram illustrating an outline of a log data transfer system according to a fourth embodiment. 18 is a flowchart illustrating a transmission processing procedure in the log transmission-side computer according to the fourth embodiment. FIG. 19 is an FEC packet format diagram showing a configuration of an FEC packet according to Embodiment 4. 19 is a flowchart illustrating a reception processing procedure in the log receiving-side computer according to the fourth embodiment. FIG. 14 is a configuration diagram schematically showing a log data transfer system according to a fifth embodiment. 33 is a flowchart illustrating a transmission processing procedure in the log transmission-side computer according to the fifth embodiment. FIG. 15 is a log packet format diagram showing a configuration of a log packet according to the fifth embodiment. 32 is a flowchart illustrating a reception processing procedure in the log receiving-side computer according to the fifth embodiment. FIG. 13 is a configuration diagram illustrating an outline of a log data transfer system according to a sixth embodiment. 32 is a flowchart illustrating a transmission processing procedure in the log transmission-side computer according to the sixth embodiment. FIG. 15 is a log packet format diagram showing a configuration of a log packet in a sixth embodiment. FIG. 19 is an FEC packet format diagram showing a configuration of an FEC packet according to a sixth embodiment. 32 is a flowchart illustrating a reception processing procedure in the log receiving-side computer according to the sixth embodiment.

  Hereinafter, the details of the operation in the configuration of the log data transfer method and the log data transfer system according to the embodiment of the present invention will be described with reference to FIGS. 1 to 26.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram schematically showing a log data transfer system according to the first embodiment, FIG. 2 is a flowchart showing a transmission processing procedure in a log transmission side computer, and FIG. FIG. 4 is a diagram for explaining a method of generating FEC data, FIG. 5 is an FEC packet format diagram showing the configuration of an FEC packet, and FIG. It is a flowchart which shows the receiving processing procedure in a log receiving side computer. FIG. 7 is a diagram for explaining a data restoration method.

  As shown in FIG. 1, the log data transfer system 1 according to the first embodiment transmits data to the log transmission side computer 11, the log reception side computer 21, and the log transmission side computer 11 to the log reception side computer 21. And a one-way communication device 31.

  Here, the log transmission-side computer 11 includes a log data generation unit 101 for generating log data, a log data collection unit 102 for collecting the generated log data, a log packet sequence number generation unit 103 for generating a log packet sequence number, and log data. A log packet generation unit 104 that generates a log packet by adding a log packet serial number to a packet, a packet transmission unit 105 that transmits a log packet and an FEC packet, a transmitted log packet storage unit 106 that stores the transmitted log packet, An FEC data generation unit 107 that generates FEC data from the generated log packet and an FEC packet generation unit 108 that generates an FEC packet from the generated FEC data.

  The log receiving computer 21 receives a packet from the log transmitting computer 11 via the one-way communication device 31. The packet receiving unit 201 identifies whether the received packet is a log packet or an FEC packet. A received packet identification unit 202, a received log packet storage unit 203 that stores received log packets, a log packet sequence number confirmation unit 204 that confirms log packet sequence numbers, a log packet processing unit 205 that extracts log data from received log packets, a log A log packet serial number loss recording unit 207 that records a log packet serial number when a log packet serial number is lost in the log data output unit 206 that outputs data and the log packet serial number check unit 204, and a log packet of the lost log packet serial number Log packet restoring unit 208 for restoring It is.

  The one-way communication device 31 is for realizing one-way communication, and includes a receiving device 301 for receiving a packet transmitted from the log transmitting computer 11 and a transmitting device 302 for transmitting a packet to the log receiving computer 21. , A one-way communication path 310 that physically connects the receiving device 301 and the transmitting device 302 in one direction.

  Next, the operation of the log data transfer method and the log data transfer system according to the first embodiment will be described with reference to FIGS.

First, the transmission process in the log transmission-side computer 11 will be described with reference to FIG.
In step S101, the log data collection unit 102 collects the log data 41b generated by the log data generation unit 101.

  In step S102, the log packet sequence number generation unit 103 generates a log packet sequence number 41a corresponding to the collected log packet 41. Here, the log packet serial number 41a is an identifier that can detect loss of the serial number when the log packet serial number 41a is partially lost, such as an integer string starting from 1, for example.

  In step S103, the log packet generation unit 104 generates the log packet 41 in which the log packet serial number 41a generated in step S102 is added to the log data 41b collected in step S101. Here, the log packet 41 is communication data composed of a log packet serial number 41a and log data 41b as shown in the log packet format of FIG.

  In step S104, the log transmitting unit 105 transmits the log packet 41 generated in step S103 to the log receiving computer 21.

  In step S105, after the transmitted log packet 41 is transmitted in step S104 by the transmitted log packet storage unit 106, the transmitted log packet 41 is stored.

  In step S106, the number of log packets 41 stored in the transmitted log packet storage unit 106 is counted, and it is determined whether the number is a fixed number (for example, M in this case). When the number of the log packets 41 is less than the fixed number M, the transmission processing in the log transmission-side computer 11 ends. If the number of log packets 41 is a fixed number M, the process proceeds to step S107. Here, M is an integer of 2 or more. For example, in a log data transfer system to be applied, an arbitrary numerical value whose number is less than or equal to 1 assuming a probability that a loss occurs in the continuous log data 41b. Can be set to

  In step S107, the FEC data generation unit 107 generates the FEC data 42b. Here, in the example of the method of generating the FEC data illustrated in FIG. 4, the log data # 1 to #M included in each of the stored M log packets 41 is set as a set, and the XOR (XOR ( Exclusive OR) is calculated to generate FEC data # 1.

  In step S108, the FEC packet generation unit 108 generates the FEC packet 42 based on the generated FEC data 41b. Here, as shown in the FEC packet format of FIG. 5, the FEC packet 42 is a communication packet composed of a log packet serial number 42a of the M log packets 41 from which the FEC data is generated and the FEC data 42b. It is data.

  Subsequently, in step S109, the generated FEC packet 42 is transmitted to the log receiving computer 21 by the packet transmission unit 105.

  Finally, in step S110, after the FEC packet 42 has been transmitted, the log packet 41 stored in the transmitted log packet storage unit 106 is deleted. Thus, the transmission process in the log transmission side computer 11 is completed.

Next, the receiving process in the log receiving computer 21 will be described with reference to FIG.
In step S201, the packet (the log packet 41 and the FEC packet 42) transmitted from the log transmitting computer 11 is received by the packet receiving unit 201.

  In step S202, the received packet identification unit 202 identifies whether the received packet is the log packet 41 or the FEC packet 42. When the received packet is identified as the log packet 41, the process proceeds to step S203, and when the received packet is identified as the FEC packet 42, the process proceeds to step S208.

  In step S203, if the received packet is the log packet 41 in step S202, the received log packet 41 is stored by the received log packet storage unit 203.

  In step S204, the log packet sequence number confirmation unit 204 detects whether or not the received log packet 41 has a loss of the log packet sequence number 41a. When it is confirmed that there is no loss in the log packet serial number 41a, the process proceeds to step S205, and when it is confirmed that there is a loss in the log packet serial number 41a, the process proceeds to step S207.

  In step S205, when it is confirmed in step S204 that there is no loss in the log packet serial number 41a, the log packet processing unit 205 extracts the log data 41b from the received log packet 41.

  In step S206, the log data output unit 206 outputs the extracted log data 41b in step S205. Thus, the receiving process in the log receiving computer 21 ends.

  In step S207, if there is a loss of the log packet serial number 41a in step S204, the loss of the log packet serial number 41a is recorded by the log packet serial number loss recording unit 207, and the receiving process in the log receiving computer 21 is ended. You.

  On the other hand, in step S208, if the received packet is identified as the FEC packet 42 in step S202, the log packet restoring unit 208 outputs the M log records recorded in the received FEC packet 42. It is confirmed whether any of the packet serial numbers 42a is missing. When it is confirmed that there is no loss in the log packet serial number 42a, the receiving process in the log receiving computer 21 is ended. If it is confirmed that there is a loss in the log packet serial number 42a, the process proceeds to step S209.

  In step S209, if the log packet serial number 42a is missing in step S208, the missing log packet 41 is restored by the log packet restoring unit 208. Here, as an example of a case where the log data # 2 has a loss, as shown in the data restoration method of FIG. 7, the log data included in each of the saved M log packets 41 is set as one set. By calculating the XOR of all the log data # 1 to #M and the FEC data # 1, the log data # 2 included in the lost log packet 41 is restored.

  In step S210, the received log packet storage unit 203 stores the restored log packet 41.

  In step S211, the log packet sequence number confirming unit 204 confirms that the loss of the log packet sequence number 42 a has been resolved, and the log packet processing unit 205 performs log conversion from the log packet 41 in which the loss of the log packet sequence number 42 a has been resolved. The data 41b is extracted.

  In step S212, the log data output unit 206 outputs the extracted log data 41b. Thus, the receiving process in the log receiving computer 21 ends.

  Note that the log packet 41 stored in the received log packet storage unit 203 is deleted if there is no loss in the log packet serial number 41a and the corresponding FEC packet 42 has been received. Here, if the FEC packet 42 is missing, the saved log packet 41 cannot be deleted, but in this case, a timeout value or the like is set in advance, and after a certain time has elapsed, the saved log packet 41 is deleted. The packet 41 is deleted.

  As described above, according to the log data transfer method and the log data transfer system according to the first embodiment, it is possible to detect the loss of log data by adding the log packet serial number to the transmitted log data. In addition, by generating FEC data from consecutive M log data, there is an effect that it is possible to restore a single loss of log data due to a random error.

Embodiment 2 FIG.
FIG. 8 is a flowchart illustrating a transmission processing procedure in the log transmission-side computer in the log data transfer system according to the second embodiment. FIG. 9 is a diagram illustrating a method of generating FEC data. The configuration of the log data transfer system according to the second embodiment is the same as the configuration of the log data transfer system 1 according to the first embodiment shown in FIG.

  In the log data transfer system 1 according to the first embodiment, by generating FEC data from consecutive M log data, one log packet out of M log packets due to a random error is lost. In such a case, it is possible to restore the log packet, but if continuous log packets such as a burst error are missing, the log data cannot be restored.

  On the other hand, in the log data transfer system according to the second embodiment, at the time of generating FEC data, the log data transfer system shown in FIG. By using N error correction FEC data generated from the N pieces of log data, even if a maximum of N consecutive log packets are lost due to a burst error, the log data is restored. It becomes possible. Here, the matrix composed of M × N log data is composed of N sets of M log data acquired every N pieces from continuous log data. In other words, the M log data is set as a set obtained at a certain time interval (every N data).

  Note that the log packet format, the FEC packet format, and the method of restoring log data are the same as those in the first embodiment, and a description thereof will not be repeated.

  Next, the operation of the log data transfer method and the log data transfer system according to the second embodiment will be described with reference to FIGS.

First, a transmission process in the log transmission-side computer 11 will be described with reference to FIG.
Steps S101 to S105 and step S110 are the same as the operations of the log transmitting computer 11 in FIG. 2 of the first embodiment, except that steps S106 to S109 are replaced with steps S301 to S304. Description is omitted because there is.

  In step S301, the number of log packets 41 stored in the transmitted log packet storage unit 106 is counted, and it is determined whether the number is a predetermined number (for example, M × N here). When the number of the log packets 41 is less than the predetermined number M × N, the transmission processing in the log transmission-side computer 11 ends. If the number of log packets 41 is the predetermined number M × N, the process proceeds to step S302. Here, the number M is an integer of 2 or more, and the number N is an integer of 1 or more (where N = 1 corresponds to the case of the first embodiment). For example, in an applied log data transfer system, Assuming the maximum probability that a continuous loss occurs in continuous log data, the number can be set to an arbitrary numerical value such that the number is within N.

  In step S302, when the number of stored log packets 41 is M × N, the FEC data generation unit 107 generates N FEC data 42. Here, in the example of the generation method of the FEC data illustrated in FIG. 9, a matrix 43 of M rows and N columns composed of M × N log data of the stored log packet 41 is generated, and M rows and XOR of the log data is calculated, and FEC data # 1 to #N are generated.

  In step S303, the FEC packet generator 108 generates N FEC packets 42 based on the generated N FEC data 42b.

  Subsequently, in step S304, the packet transmitting unit 105 transmits the generated N FEC packets 42 to the log receiving computer 21.

  Finally, in step S110, after the FEC packet 42 has been transmitted, the log packet 41 stored in the transmitted log packet storage unit 106 is deleted. Thus, the transmission process in the log transmission side computer 11 is completed.

  Note that the operation of the log receiving computer 21 is the same as that of the first embodiment, and therefore the description is omitted.

  As described above, according to the log data transfer method and the log data transfer system according to the second embodiment, the occurrence of log data loss can be detected by adding a log packet serial number to transmitted log data. In addition, by generating N FEC data from consecutive M × N log data, there is an effect that a loss of a maximum of N consecutive log data due to a burst error can be restored.

Embodiment 3 FIG.
FIG. 10 is a configuration diagram schematically showing a log data transfer system according to the third embodiment. FIG. 11 is a flowchart showing a transmission processing procedure in a log transmission side computer. FIG. 13 is a log packet format diagram showing the configuration, and FIG. 13 is a flowchart showing a reception processing procedure in the log receiving computer. Here, in the log data transfer system 2 according to the third embodiment of FIG. 10, the time measurement unit 401 and the transmission side dummy packet generation are performed by the log transmission side computer 11 of the log data transfer system 1 according to the first embodiment of FIG. The unit 402 is obtained by adding a receiving-side dummy packet generating unit 403 to the log receiving-side computer 21.

  In the log data transfer system 1 according to the first embodiment, by generating FEC data from consecutive M log data, one log packet out of M log packets due to a random error is lost. Can recover a log packet, but in order to generate an FEC packet, M log packets are required. In the case of intermittently generated log data, an FEC packet Cannot be generated.

  On the other hand, in the log data transfer system 2 according to the third embodiment, even if a predetermined time has elapsed, if M log packets have not been collected, a dummy packet is added and M log packets are added. Since the FEC packet can be generated in real time by generating the FEC packet so as to be the log packet, the real-time property of the log data transfer can be improved.

  Note that the log packet format, the FEC packet format, and the method of restoring log data are the same as those in the first embodiment, and a description thereof will not be repeated.

  Next, the operation of the log data transfer method and the log data transfer system according to the third embodiment will be described with reference to FIGS.

First, transmission processing in the log transmission side computer 12 will be described with reference to FIG.
Except that steps S401 to S404 are added, steps S101 to S110 are the same as the operations of the log transmission side computer 11 of FIG.

  In step S401, when the number of the log packets 41 stored in the transmitted log packet storage unit 106 is one, the time is acquired and recorded by the time measurement unit 401. That is, the time at which the first log packet 41 was transmitted is recorded.

  In step S106, the number of log packets 41 stored in the transmitted log packet storage unit 106 is counted, and it is determined whether the number is a predetermined number (for example, M in this case). If the number of log packets 41 is the predetermined number M, the process moves to step S107, and the same processing as in the first embodiment is performed. If the number of log packets 41 is less than the predetermined number M, the process moves to step S402.

  In step S402, the time measuring unit 401 determines whether a predetermined time has elapsed from the recorded time. If the time is less than the predetermined time, the transmission processing in the log transmission-side computer 12 ends. If the predetermined time has elapsed, the process moves to step S403. Here, the predetermined time may be, for example, a time during which M log packets can be generated and transmitted in normal processing.

  In step S403, the transmission-side dummy packet generation unit 402 generates (M- (the number of stored log packets 41)) transmission-side dummy packets 44. Here, the transmission-side dummy packet 44 includes a dummy packet serial number 44a and dummy data 44b, as shown in the dummy packet format of FIG.

  In step S404, after the transmission-side dummy packet 44 is generated, the FEC data generation unit 107 generates the FEC data 42b based on the saved log packet 41 and the generated dummy data 44b of the transmission-side dummy packet 44. Is done. Thereafter, the process proceeds to step S108.

  In step S108, the FEC packet generation unit 108 generates the FEC packet 42 from the FEC data 42b. Here, the FEC packet 42 includes a log packet serial number 42a, a dummy packet serial number 44a, and an FEC data 42b from which the FEC data is generated.

  After that, as in the first embodiment, the FEC packet 42 is transmitted by the packet transmission unit 105 in step S109, and the log packet 41 stored in the transmitted log packet storage unit 106 is deleted in step S110. . Thus, the transmission process in the log transmission side computer 12 is completed.

Next, the receiving process in the log receiving computer 22 will be described with reference to FIG.
Except that steps S411 to S413 are added, steps S201 to S207 and steps S210 to S212 are the same as the operations of the log receiving computer 21 in FIG. Is omitted.

  In step S411, if the received packet is identified as the FEC packet 42 in step S202, the log packet restoring unit 208 causes the log packet restoring unit 208 to output the M log packet serial numbers recorded in the received FEC packet 42. It is confirmed whether any one of 42a is missing. When it is confirmed that there is no loss in the log packet serial number 42a, the receiving process in the log receiving computer 21 is ended. If it is confirmed that there is a loss in the log packet serial number 42a, the process proceeds to step S412.

  In step S412, since it is confirmed in step S411 that the log packet 41 is missing, the reception-side dummy packet generation unit 403 generates the reception-side dummy packet 44. At this time, based on the dummy packet serial number 44a included in the FEC packet 42, the receiving-side dummy data 44b identical to the data generated by the transmitting-side dummy packet generator 402 is generated.

  In step S413, when there is a loss in the log packet serial number 42a, the log packet recovery unit 208 recovers the lost log packet 41 from the receiving-side dummy data 44b and the log data 41b. The data restoration method is the same as the data restoration method described with reference to FIG.

  Hereinafter, in steps S210 to S212, as in the first embodiment, the received log packet storage unit 203 stores the restored log packet 41, and the log packet sequence number confirmation unit 204 determines whether the log packet sequence number 42a is missing. It is confirmed that the log packet 41 has been resolved, and the log packet processing unit 205 retrieves and outputs the log data 41b from the log packet 41 in which the loss of the log packet serial number 42a has been resolved. Thus, the receiving process in the log receiving computer 22 ends.

  As described above, according to the log data transfer method and the log data transfer system according to the third embodiment, it is possible to detect the loss of log data by adding the log packet serial number to the transmitted log data. Also, by generating FEC data from consecutive M log data, loss of log data due to an error can be restored, and even after a predetermined time has elapsed, M log packets are not aligned. In this case, the FEC packet can be generated in real time by adding a dummy packet to generate M FEC packets so as to become M log packets, thereby realizing the real-time property of the log data transfer. There is an effect that it can be improved.

Embodiment 4 FIG.
FIG. 14 is a configuration diagram showing an outline of a log data transfer system according to the fourth embodiment. FIG. 15 is a flowchart showing a transmission processing procedure in a log transmission-side computer. FIG. 17 is a flowchart showing a reception processing procedure in the log receiving-side computer. Here, in the log data transfer system 3 according to the fourth embodiment of FIG. 14, a time measurement unit 401 is added to the log transmission side computer 11 of the log data transfer system 1 according to the first embodiment of FIG. The generation unit 107 is replaced by an FEC data generation unit 501, the FEC packet generation unit 108 is replaced by an FEC packet generation unit 502, and the log packet restoration unit 208 of the log receiving computer 21 is replaced by a log packet restoration unit 503. It was done.

  In the log data transfer system 2 according to the third embodiment, a real-time property at the time of log transfer is improved by generating an FEC packet using a dummy packet after a predetermined time has elapsed. However, at this time, at the time of generating FEC data and restoring the log packet, it is necessary to calculate M XORs including the dummy packet, and an unnecessary calculation is performed for the dummy packet.

  On the other hand, in the log data transfer system 3 according to the fourth embodiment, even if the predetermined number of log packets have not been collected after the elapse of the predetermined time, the number M of the currently stored log packets is reduced to M. FEC data is generated accordingly. That is, in the first to third embodiments, the number M is a fixed value, but in the fourth embodiment, the number M is a variable value. This eliminates the need for the dummy data generation processing as in the third embodiment, so that the calculation processing load during FEC data generation and log packet restoration can be reduced, and the processing speed can be improved.

  Note that the log packet format and the method of restoring log data are the same as those in the first embodiment, and thus description thereof is omitted.

  Next, the operation of the log data transfer method and the log data transfer system according to the fourth embodiment will be described with reference to FIGS.

First, the transmission process in the log transmission side computer 13 will be described with reference to FIG.
Steps S101 to S106 and steps S109 to S110 are the same as those of the first embodiment except that steps S401 and S402 are added, and steps S107 and S108 are replaced with steps S501 and S502. Since the operation is the same as that of the log transmission side computer 11 in FIG. 2, the description is omitted.

  In step S401, when the number of the log packets 41 stored in the transmitted log packet storage unit 106 is one, the time is acquired and recorded by the time measurement unit 401. That is, the time at which the first log packet 41 was transmitted is recorded.

  In step S106, the number of log packets 41 stored in the transmitted log packet storage unit 106 is counted, and it is determined whether the number is a predetermined number (for example, M in this case). If the number of the log packets 41 is M, the process proceeds to step S107, and the same processing as in the first embodiment is performed. If the number of log packets 41 is less than the predetermined number M, the process moves to step S402.

  In step S402, the time measuring unit 401 determines whether a predetermined time has elapsed from the recorded time. If the time is less than the predetermined time, the transmission processing in the log transmission-side computer 13 ends. If the predetermined time has elapsed, the process moves to step S501. Here, the predetermined time may be, for example, a time during which M (fixed) log packets can be generated and transmitted in normal processing.

  In step S501, the FEC data generation unit 501 generates FEC data. Here, in the example of the method of generating the FEC data illustrated in FIG. 4, the log data # 1 to #M included in each of the stored M log packets 41 is set as a set, and the XOR (XOR ( Exclusive OR) is calculated to generate FEC data # 1. However, if the predetermined time has elapsed in step S402, FEC data is generated with the number M (variable value) of the stored log data.

  In step S502, the FEC packet 45 is generated by the FEC data generation unit 501 based on the generated FEC data. As shown in the FEC packet format of FIG. 16, the generated FEC packet 45 includes the number 45n of log packets from which the FEC data is generated, the log packet serial number 45a, and the FEC data 45b.

  Thereafter, as in the first embodiment, the FEC packet 45 is transmitted by the packet transmission unit 105 in step S109, and the log packet 41 stored in the transmitted log packet storage unit 106 is deleted in step S110. . Thereby, the transmission process in the log transmission side computer 13 is completed.

Next, the receiving process in the log receiving computer 23 will be described with reference to FIG.
Except that step S209 is replaced by step S503, steps S201 to S208 and steps S210 to S212 are the same as the operations of the log receiving computer 21 of FIG. Is omitted.

  In step S208, if it is determined in step S202 that the received packet is the FEC packet 45, the log packet restoring unit 503 records the M packets (variable values) recorded in the received FEC packet 45. It is confirmed whether any of the log packet serial numbers 45a is missing. When it is confirmed that there is no loss in the log packet serial number 45a, the receiving process in the log receiving computer 23 is ended. If it is confirmed that there is a loss in the log packet serial number 45a, the process moves to step S503.

  In step S503, if there is a loss in the log packet serial number 45a, the log packet recovery unit 503 recovers the lost log packet 41. The data restoring method is the same as the data restoring method described in FIG. 7 of the first embodiment. Here, the difference from the first embodiment is that the number M of the log packets 41 is a variable value.

  Hereinafter, in steps S210 to S212, as in the first embodiment, the received log packet storage unit 203 stores the restored log packet 41, and the log packet sequence number confirmation unit 204 determines whether the log packet sequence number 45a is missing. It is confirmed that the log data has been resolved, and the log packet processing unit 205 retrieves and outputs log data from the log packet 41 in which the loss of the log packet serial number has been resolved. Thus, the receiving process in the log receiving computer 23 is completed.

  As described above, according to the log data transfer method and the log data transfer system according to the fourth embodiment, the occurrence of log data loss can be detected by adding a log packet serial number to transmitted log data. Also, by generating FEC data from consecutive M log data, loss of log data due to an error can be restored, and even after a predetermined time has elapsed, M log packets are not aligned. In this case, by generating FEC data in accordance with the number M of log packets currently stored, the processing load at the time of generating FEC data and restoring log packets can be reduced, and the processing speed can be improved. This has the effect.

Embodiment 5 FIG.
FIG. 18 is a configuration diagram showing an outline of the log data transfer system according to the fifth embodiment. FIG. 19 is a flowchart showing a transmission processing procedure in a log transmission side computer. FIG. FIG. 21 is a flowchart of a receiving process performed by the log receiving computer. Here, in the log data transfer system 4 according to the fifth embodiment in FIG. 18, the log data dividing unit 601 is provided in the log transmission side computer 11 of the log data transfer system 1 in the first embodiment in FIG. The log data combining unit 602 is added to the computer 21.

  In the log data transfer system 1 according to the first embodiment, even when the log data becomes long, the process of dividing the log data is not executed. However, if the log data is long, packets may be divided in the lower layer of the network, and the load on the log receiving computer may increase.

  For example, in the case of UDP / IP, when a UDP (User Data Protocol) datagram becomes large, the datagram is divided into a plurality of IP packets in a lower IP layer according to an MTU (Maximum Transmission Unit) and transmitted. Then, on the receiving side, a process of restoring a UDP datagram is executed by combining the divided IP packets in the protocol stack of the UDP layer. At this time, if a part of the divided IP packet is missing, the UDP layer protocol stack waits for the reception of the missing IP packet.

  On the other hand, in the log data transfer system 4 according to the fifth embodiment, in order to prevent such an increase in the load on the log receiving side computer, when the log data becomes longer, the log data division system divides the log data. Part is provided. By dividing a packet at the time of transmission, it is possible to prevent packet division in a lower layer of the network and prevent an increase in load on the log receiving side computer.

  Note that the FEC packet format and the method of restoring log data are the same as those in the first embodiment, and a description thereof will be omitted.

  Next, the operation of the log data transfer method and the log data transfer system according to the fourth embodiment will be described with reference to FIGS.

First, a transmission process in the log transmission-side computer 14 will be described with reference to FIG.
Except for the point that step S601 is added, steps S101 to S110 are the same as the operations of the log transmitting computer 11 of FIG.

  In step S101, the log data collection unit 102 collects the log data 41b generated by the log data generation unit 101.

  In step S601, if the length of the collected log data is longer than the determined length, the log data dividing unit 601 divides the log data 41b. Here, the length of the log data to be divided is set to be equal to or less than the MTU of the network to be used.

  In step S102, the log packet sequence number generation unit 103 generates a log packet sequence number 46a corresponding to the divided log data 46b.

  In step S103, the log packet generation unit 104 generates the log packet 46 in which the log data serial number 46a is added to the log data 46b divided by the log data division unit 601. The log packet 46 generated here includes a log packet serial number 46a, a divided packet identifier 46f, and divided log data 46b, as shown in the log packet format of FIG.

  Thereafter, as in the first embodiment, the log packet 46 and the FEC packet 42 are transmitted by the packet transmission unit 105 in steps S104 and S109, and are stored in the transmitted log packet storage unit 106 in step S110. The log packet 46 is deleted. Thus, the transmission processing in the log transmission-side computer 14 ends.

Next, the receiving process in the log receiving computer 24 will be described with reference to FIG.
Except that steps S602 and S603 are added, steps S201 to S212 are the same as the operations of the log receiving computer 21 of FIG.

  In step S205, when it is confirmed in step S204 that there is no loss in the log packet serial number 46a, the log packet processing unit 205 extracts the log data 46b from the received log packet 46.

  In step S602, the log data is combined by the log data processing unit 205 by the log data combining unit 602 based on the divided packet identifier 46f.

  Similarly, if there is a loss in the log packet serial number 46a, the lost log packet 46 is restored by the log packet restoration unit 208. Further, in step S603, the log data extracted by the log packet processing unit 205 is The log data combining unit 602 combines the log data 46b based on the fragmented packet identifier 46f.

  In steps S206 and S212, the log data output unit 206 outputs the extracted log data 41b. Thus, the receiving process in the log receiving computer 24 is completed.

  As described above, according to the log data transfer method and the log data transfer system according to the fifth embodiment, it is possible to detect the occurrence of loss of log data by adding a log packet serial number to transmitted log data. In addition, by generating FEC data from consecutive M log data, loss of log data due to an error can be restored, and when log data is long, log data is divided in advance and log packets are generated. By generating the packet, there is an effect that packet division on the network can be prevented, and the load on the receiving side can be reduced.

Embodiment 6 FIG.
FIG. 22 is a configuration diagram showing an outline of the log data transfer system according to the sixth embodiment, FIG. 23 is a flowchart showing a transmission processing procedure in a log transmission side computer, and FIG. 24 is a configuration of a log packet. FIG. 25 is an FEC packet format diagram showing the configuration of an FEC packet, and FIG. 26 is a flowchart showing a reception processing procedure in the log receiving-side computer. Here, in the log data transfer system 5 according to the sixth embodiment of FIG. 22, the checksum calculation unit 701 is added to the log transmission side computer 11 of the log data transfer system 1 according to the first embodiment of FIG. The checksum check unit 703 is added to the computer 21.

  In the log data transfer system 1 according to the first embodiment, the calculation of the checksum is not performed when transmitting the log packet and the FEC packet. However, if the calculation of the checksum is not performed, the contents of the log data may be garbled in the lower layer of the network.

  For example, in the IPv4 UDP, the calculation of the checksum of the UDP layer is optional. If the checksum of the UDP layer is invalidated due to the configuration of the system, there is a possibility that erroneous data is received on the receiving side.

  On the other hand, in the log data transfer system 5 according to the sixth embodiment, in order to prevent reception of erroneous data at the log receiving computer, the checksum of the log packet and the FEC packet is calculated before transmitting the data. I do. By confirming the checksum on the receiving side, the possibility of receiving erroneous log data can be reduced.

  Note that the method of restoring log data is the same as in the first embodiment, and a description thereof will not be repeated.

  Next, the operation of the log data transfer method and the log data transfer system according to the sixth embodiment will be described with reference to FIGS.

First, a transmission process in the log transmission side computer 15 will be described with reference to FIG.
Except for the point that step S701 is added, steps S101 to S110 are the same as the operations of the log transmission-side computer 11 of FIG.

  In step S701, the log packet generation unit 104 calculates the checksum of the generated log packet 41, and adds the checksum 47s to the log packet 41. Thus, the log packet 47 is composed of the checksum 47s, the log packet serial number 47a, and the log data 47b, as shown in FIG.

  In step S702, the checksum of the FEC packet 42 generated by the FEC packet generator 108 is calculated, and the checksum 48s is added to the FEC packet 42. As a result, the FEC packet 48 is composed of the checksum 48s, the log packet serial number 48a, and the log data 48b, as shown in FIG.

  Thereafter, as in the first embodiment, the log packet 47 and the FEC packet 48 are transmitted by the packet transmission unit 105 in steps S104 and S109, and are stored in the transmitted log packet storage unit 106 in step S110. The log packet 47 is deleted. Thus, the transmission processing in the log transmission side computer 15 is completed.

Next, the receiving process in the log receiving computer 25 will be described with reference to FIG.
Except that step S703 is added, steps S201 to S212 are the same as the operations of the log receiving computer 21 of FIG.

  In step S703, the checksum of the log packet 47 and the FEC packet 48 received by the packet receiving unit 201 is confirmed. If the checksum 48s is determined to be correct, the process proceeds to step S202, and the first embodiment is performed. Similarly, the following steps are executed. If it is determined that the checksum 48s is incorrect, the log packet 47 is discarded, and the receiving process in the log receiving computer 25 is terminated.

  As described above, according to the log data transfer method and the log data transfer system according to the sixth embodiment, the occurrence of log data loss can be detected by adding the log packet serial number to the transmitted log data. In addition, by generating FEC data from consecutive M log data, it is possible to restore the loss of log data due to an error, and to calculate the checksum of the log packet and the FEC packet to obtain an erroneous data. This has the effect of reducing the possibility of receiving log data.

  In the above embodiment, an example in which a unidirectional communication device is used between a transmission side computer and a reception side computer to explain that the present invention is effective in a log data transfer system that cannot retransmit log data, which is a feature of the present invention. However, it is needless to say that the present invention can be applied to a general network system.

  Further, each unit configuring the log transmission computer and the log reception computer may be configured by either hardware or software.

  Further, in the present invention, within the scope of the present invention, it is possible to freely combine the embodiments, and to appropriately modify or omit the embodiments.

  In the drawings, the same reference numerals indicate the same or corresponding parts.

    1, 2, 3, 4, 5 log data transfer system, 11, 12, 13, 14, 15 log transmitting computer, 21, 22, 23, 24, 25 log receiving computer, 31 one-way communication device, 41, 46, 47 log packet, 42, 45, 48 FEC packet, 44 dummy packet, 101 log data generation unit, 102 log data collection unit, 103 log packet serial number generation unit, 104 log packet generation unit, 105 packet transmission unit, 106 transmission Log packet storage unit, 107, 501 FEC data generation unit, 108, 502 FEC packet generation unit, 201 packet reception unit, 202 received packet identification unit, 203 received log packet storage unit, 204 log packet sequence number confirmation unit, 205 log Packet processing unit, 206 log data output unit, 207 log packet G number recording unit, 208, 503 log packet restoration unit, 401 time measurement unit, 402 transmission side dummy packet generation unit, 403 reception side dummy packet generation unit, 601 log data division unit, 602 log data combination unit, 701 checksum Operation unit, 703 Checksum confirmation unit

Claims (12)

  On the transmitting side, a log packet serial number is added to the log data to generate a log packet, and forward error correction data generated by calculating an exclusive OR using a set of the M consecutive log data as a set To generate a forward error correction packet, transmit the log packet and the forward error correction packet, and receive the log packet serial number of the forward error correction packet on the receiving side. In the case where it is detected that a loss has occurred in any one of the above, the exclusive OR of the received set of log data and the forward error correction data is calculated to restore the log packet, and the restoration is performed. A log data transfer method characterized by extracting log data from a given log packet.   2. The log data transfer method according to claim 1, wherein the M consecutive log data are M log data acquired every N log data from the continuous log data.   On the transmitting side, if the M log packets are not aligned within a predetermined time based on the time at which the first log packet was transmitted, a transmitting side dummy packet is added to the log packet, The log data transfer method according to claim 1, wherein the receiving side adds receiving-side dummy data to the received log data. On the transmitting side,
By the first of the log packet to generate the forward error correction packets appends the number M of the log packets generated continuously within a predetermined time based on the time sent, the number of said log packet 2. The log data transfer method according to claim 1, wherein M is a variable value.   The log data transfer method according to claim 1, wherein the log data is divided on the transmission side, and the divided log data is combined on the reception side.   2. The log data transfer method according to claim 1, wherein the transmission side calculates a checksum of the log packet, and the reception side confirms the calculated checksum. A log packet generation unit that generates a log packet in which a log packet serial number is added to log data;
Forward error correction packet generation for generating a forward error correction packet in which the M log packet serial numbers are added to forward error correction data generated by performing an exclusive OR operation on a set of consecutive M log data as a set Department,
A log transmitting-side computer having a packet transmitting unit that transmits the log packet and the forward error correction packet,
A packet receiving unit that receives the log packet and the forward error correction packet,
A received packet identification unit that identifies whether the log packet is the forward error correction packet and detects whether any of the log packet serial numbers of the forward error correction packet is missing.
If any of the M log packet serial numbers is missing, a log packet for calculating the exclusive OR of the received set of log data and the forward error correction data to restore the log packet Restoration unit,
A log receiving computer having a log packet processing unit for extracting log data from the restored log packet,
A log data transfer system comprising:   8. The log data transfer system according to claim 7, wherein the M consecutive log data is M log data acquired every N log data from the continuous log data. A time measuring unit that measures a predetermined time based on the time at which the first log packet is transmitted to the log transmitting computer, and generates a transmitting dummy packet in which a transmitting dummy packet serial number is added to transmitting dummy data; Transmitting side dummy packet generation unit,
The log receiving-side computer, a receiving-side dummy packet generating unit that generates a receiving-side dummy packet with a receiving-side dummy packet serial number added to a receiving-side dummy data,
In the log transmitting side computer, when the M number of the log packets are not aligned within the predetermined time, the transmitting side dummy packet is added to the log packet,
8. The log data transfer system according to claim 7, wherein the log receiving computer adds the receiving dummy packet to the received log data. In the log sending computer,
A time measuring unit that measures a predetermined time based on a time at which the first log packet is transmitted,
In the log sending computer,
The forward error correction packet generation unit may generate the forward error correction packet to which the number M of the log packets continuously generated within the predetermined time is added, so that the number M is made a variable value. The log data transfer system according to claim 7, wherein A log data dividing unit that divides the log data into the log transmitting computer;
A log data dividing unit that combines the divided log data with the log receiving computer;
The log data transfer system according to claim 7, comprising: A checksum calculating unit that calculates a checksum of the log packet in the log transmitting computer;
A checksum check unit for checking the calculated checksum to the log receiving computer;
The log data transfer system according to claim 7, comprising:

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