JPH087724B2 - Data transfer system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transfer system, and more particularly to a data transfer system which collects a plurality of data generated and accumulated in a transmitter into one file and transfers the data collectively to a receiver through a communication line.

[0002]

2. Description of the Related Art A conventional data transfer system of this type is
The transmitting device accumulates multiple pieces of data that occur from time to time, and when a specified transmission time arrives, they are organized into one file and transferred to the receiving device through the communication line, and an error in data transmission on the communication line is detected. In order to recover it, the sending device receives information indicating normal reception from the receiving device every time it sends a file, and confirms the normal end of file transfer.If the file transfer fails, the file with the same contents is sent. I was sending again.

[0003]

In the above-mentioned conventional data transfer system, when the file transfer fails, the transmitting device only transfers the file having the same content again at the next transmission opportunity, so that the file can be transmitted only at a constant time interval. When there are few transmission opportunities, the transmission of new data is delayed, resulting in a decrease in communication efficiency.

Further, when the receiving device side normally receives the file, but the control signal transmitting the normal reception is incorrect at the final stage of the communication procedure (line disconnection procedure) on the communication line, the transmitting device side transfers the file. It judges that has failed and resends the same file. For this reason, data that has already been received by the receiving device and does not need to be retransmitted is also retransmitted, which causes an increase in the capacity of the data storage memory of the transmitting device.

[0005]

The present invention is applied to a data transfer system for collectively collecting a plurality of data generated and accumulated on the transmitting device side into one file and transferring them collectively to a receiving device side through a communication line. A data accumulating means for temporarily accumulating a plurality of data in the order of input and for counting the quantity of accumulated data as a cumulative data number; a serial number counting means for counting a serial number for identifying the contents of the file; File organization means for adding the cumulative number of data and the serial number to the data stored in the data storage means to organize the file; and the file organization means connected to the receiving device via the communication line. If the confirmation information indicating the normal reception of the file is received from the receiving device, the file organized by A file transmitting means for erasing the transmitted data in the data accumulating means and incrementing the count value of the serial number counting means; and the file transmitting means is provided in the transmitting device, and is connected to the transmitting device via the communication line. File receiving means for receiving the file and returning the confirmation information to the transmitting device when the file is normally received; and for decomposing the file received by the file receiving means for decomposing the serial number, the accumulated data number and the data. A file decomposing means for obtaining each; a storage means for storing the serial number and the cumulative data number as a previous serial number and a previous cumulative data number each time the file is received; Detects whether the serial number and the previous serial number in the storage means match and matches If the serial numbers match, the difference between the current cumulative data number obtained by the file decomposing means and the previous cumulative data number stored in the storage means, and if the serial numbers do not match, New data number calculation means for making the cumulative data number this time the new data number; reception data restoration for outputting data from the last data to the new data number of the data obtained by the file decomposition means as valid data Means and; are provided in the receiving device.

Further, in the above structure, when the data is input in excess of the maximum number of data that can be stored in the data storage means, the transmission device increments the count value of the accumulated data by the oldest data. To store new data, add the maximum number of data when the file is organized by the file organizing means, and the receiving device
A means for outputting the data loss notification showing the maximum data number from the received file and comparing with the new data number, and when the new data number exceeds the maximum data number, indicating the difference between the two as the missing data number, The received data restoration means may be configured to output, as effective data, data corresponding to a smaller number of the new data number and the maximum data number.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention. A communication network 20 in which a transmission device 10 that collects a plurality of data and collectively transmits them as a file and a reception device 30 that receives a file and restores each data also accommodates other data transmission devices / reception devices not shown. Connected through. The data transfer system according to the present embodiment periodically collects and manages a certain amount of communication management data generated for each communication in a communication device such as a plurality of facsimile terminals connected to a communication network at a remote management center. It can be applied to the system.

First, the detailed structure and function of the transmitter 10 will be described. The data storage unit 11 temporarily stores a plurality of data SD1 to SDn generated on the transmission device side at any time, and outputs a count instruction Sa each time one piece of data is stored. Further, all the data stored in response to a request from the file transmission control unit 14 is output as a data read signal Sb in the order of storage, and a transmission completion notification S
When g is received, all output data is discarded. Also,
The maximum number of data Sh that indicates the maximum number of data that can be stored is output. When data exceeds the maximum number of data Sh (overflow), the oldest data is discarded and new data is stored. The cumulative data number counter 12 increments the count value by 1 in response to the count instruction Sa from the data storage unit 11, and when receiving the cumulative data number subtraction instruction Sf from the file transmission control unit 14, the count value is subtracted from the cumulative data number instruction Sf. The count value currently held is output as the cumulative data number Se indicating the number of data items stored in the data storage unit 11. The serial number counter 13 outputs the count value of the serial number currently held as the serial number Sc for identifying the contents of the file, and the count value is incremented by 1 in response to the serial number update instruction Sd from the file transmission control unit 14. Increment (however, if the count value is maximum, return to "0"). File transmission control unit 14
Starts operation in response to an instruction from a main control unit (not shown) on the transmitter side, and the data SDi to SDj stored in the data storage unit 11 by the data read signal Sb.
Is read out, and the serial number Sc, the accumulated data number Se, and the maximum data number Sh are added to this to create a transmission file, and the line interface unit 15 is instructed to transfer the file to the reception device 30. FIG. 2 shows an example of the file structure. Line interface unit 15
Makes a call to the communication network 20 through the line 21 and the receiving device 30
A connection request is made with the confirmation signal (AC
K) is monitored to determine whether the file transfer is normal or abnormal, and is output to the file transmission control unit 14 as a transfer result notification Sq, and then a connection release request with the receiving device 30 is issued to the communication network 20. The file transmission control unit 14 notifies the transfer result notification Sq.
If the file transfer is normally completed with reference to, the serial number update instruction Sd, the cumulative data number subtraction instruction Sf, and the transmission completion notification Sg are output. At this time, the cumulative data number Se added to the transmission file is set in the cumulative data number subtraction instruction Sf. When the file transfer fails, the serial number update instruction Sd, the cumulative data number subtraction instruction Sf, and the transmission completion notification Sg are not output.

Next, the detailed configuration and function of the receiving device 30 will be described. The line interface unit 31 uses the line 22.
When receiving a call from the communication network 20 through the transmission device 10, the device 10 is connected to the transmission device 10. When the file from the transmission device 10 is normally received, a confirmation signal (ACK) is returned and the received file is output to the file reception control unit 32. The file reception control unit 32 decomposes the received file only when the reception is normally completed, sets the serial number Sc as the current serial number Rcp, and sets the cumulative data number Se as the current cumulative data number R.
ep, the maximum data number Sh is the maximum data number Rh,
The data SDi to SDj are output as reception data RDi to RDj, respectively. When the storage unit 33 receives the current serial number Rcp and the current cumulative data number Rep from the file reception control unit 32, the storage unit 33 stores these and at the same time receives the “current serial number Rcp” and the “current cumulative data number” at the same time. Rep "is set to" previous serial number Rcl "and" previous accumulated data number Rel ", respectively.
Output as The serial number comparison unit 34 includes the storage unit 3
The previous serial number Rcl from 3 and the current serial number Rcp from the file reception control unit 32 are compared, and if they are different, the serial number update notification Rk is output as a value indicating "updated". If both are the same, the serial number update notification Rk is output with a value indicating "no update". When the serial number update notification Rk is “no update”, the cumulative data number comparison unit 35 determines the difference between the current cumulative data number Rep from the file reception control unit 32 and the previous cumulative data number Rel from the storage unit 33. If the serial number update notification Rk is "updated", the calculated absolute value is output as the current cumulative data number Rep itself as the new data number Rn. Maximum data number comparison unit 36
Compares the maximum data number Rh from the file reception control unit 32 with the new data number Rn from the cumulative data number comparison unit 35, and if the new data number Rn does not exceed the maximum data number Rh, issues a data loss notification Rm. When the new data number Rn exceeds the maximum data number Rh, the data loss notification Rm is set to a value indicating "missing" and output together with the difference. Received data restoration unit 3
When 7 receives the signal of the new data number Rn, the received data R
From the final data of Di to RDj, data for the new data number Rn is valid (however, if the data loss notification Rm is “missing”, all received data RDi to RDj are valid).
And outputs the valid reception data together with the data loss notification Rm to a main controller (not shown) on the receiving device side. FIG. 3 shows a data recovery operation flow of the receiving device 30. The case where the data loss notification Rm is "missing" means that the new data number Rn exceeds the maximum data number Rh, and the total number of received data RDi to RDj is equal to the maximum data number Rh. Also, serial number update notification Rk
Is "updated", the total number of received data RDi to RDj is equal to the new data number Rn. In this way, when the transmitting device 10 repeats the creation and transmission of the file to transfer all the input data SD1 to SDn, the receiving device 3
0 can be received as valid reception data RD1 to RDn, and if there is data loss, the position and number of the data loss can be known.

Next, the operation of this embodiment will be described with reference to FIG. 4 showing the sequence of data transfer between the transmitting device 10 and the receiving device 30.

At the time of initialization, the count value of the serial number counter 13 of the transmitter 10 is set to "1" and the count value of the cumulative data number counter 12 is set to "0", and the previous value of the storage unit 33 of the receiver 30 is set. The value of the serial number Rcl is set to "0" and the value of the previous cumulative data number Rel is set to "0".

At the time t in the data storage unit 11 of the transmitter 10.
A predetermined number of bits of data A to I are input for each 1 to t9. The data storage unit 11 can store five pieces of data, and when overflowing, the oldest data is deleted. Also, every time data is stored in the data storage unit 11, the count value of the cumulative data number counter 12 is incremented by "1". At time T1 after the input of the three data A to C, the file transmission control unit 14
Necessary information is read from the data storage unit 11, the serial number counter 13 and the accumulated data number counter 12, and the serial number SC is set to "1", the maximum data number Sh is set to "5", and the accumulated data number Se is set to the data A to C. The file 410 to which the management information section of "3" is added is organized. The line interface unit 15 is connected to the line interface unit 31 of the receiving device 30 through the communication network 20 and transfers the file 410 according to a predetermined protocol. When the line interface unit 31 on the receiving side normally receives the file 410, the confirmation signal (ACK) 411 is returned to the line interface unit 15 on the transmitting side. When the file reception control unit 32 of the receiving device 30 receives the file 410 through the line interface unit 31, the current serial number Rcp is “1”, the maximum data number Rh is “5”, and the current cumulative data number Rep is “3”. Output as. The serial number comparison unit 34 recognizes that the serial number has been updated because the previous serial number Rcl in the storage unit 33 is “0” for “1” of the current serial number Rcp, and the serial number update notification is issued. Set Rk to "updated". When the cumulative data number comparison unit 35 detects that the serial number update notification Rk is “updated”, it recognizes that all the data are new data, and sets the new data number Rn to “3” which is the same as the current cumulative data number Rep. Set to ". The maximum data number comparison unit 36 indicates that the new data number Rn of “3” is the maximum data number Rn.
Since it does not exceed "5" of h, it recognizes that there is no data loss and sets the data loss notification Rm to "no loss". The reception data restoration unit 37 is the file reception control unit 3.
New data number R from the final data C of the received data of 2
Three pieces of data designated by n, that is, all the data A to C are set as valid reception data and output together with the data loss notification Rm. On the other hand, when the line interface unit 15 of the transmission device 10 receives the ACK 411, it recognizes that the file transfer is normally completed, sets the transfer result notification Sq to “normal end”, and notifies the file transmission control unit 14.
When the file transmission control unit 14 recognizes that the file transfer is normally completed, the transmission completion notification Sg is used to erase all the accumulated data A to C in the data accumulation unit 11, and the serial number update instruction Sd is used to count the serial number counter 13. The value is advanced from "1" to "2", and the count value of the cumulative data number counter 12 is decremented by "3" by the cumulative data number subtraction instruction Sf. Therefore, when the data D is input at time t4, only the data D is accumulated in the data accumulating unit 11 and the accumulated data number Se becomes "1".

Next, at time T2, the transmitter 10
Serial number Sc is "2", maximum data number Sh is "5"
Data D to F are stored in the management information section where the cumulative data number Se is "3".
The file 420 added to the above is organized and sent to the receiving device 30. If the ACK 421 for this file 420 is not returned to the transmission device 10 due to some failure, the transmission device 10 recognizes that the file transfer has failed and does not perform any processing for it and waits for the next transmission opportunity. ACK4
There are two possible reasons why 21 is not returned to the transmitting device 10, and the processing of the receiving device 30 is different. (B) When the receiving device 30 successfully receives the file 420 but fails to return the ACK 421.

In this case, the receiving device 30 determines that the serial number Rcp of this time is "2" and the serial number Rcl of the previous time is Rcl.
Is different from "1", all the received data D to F are valid. (B) The receiving device 30 fails to receive the file 420,
When ACK421 is not returned.

In this case, the receiving device 30 does not perform any processing and maintains the previous processing state.

In the transmitting device 10, when the transfer of the file 420 fails, the accumulated data D to F in the data accumulating unit 11 are not erased, the data G to I are accumulated, and the next transmission opportunity (time T3 or T4) arrives. Then the serial number S
With c being the same as the previous time (“2”), a new file is reorganized and transmitted to the receiving device 30. When the file 430 is transmitted at time T3, since the data D to H are stored in the data storage unit 11 and the cumulative data number Se is “5”, which does not exceed the maximum data number Sh “5” yet. There is no data loss. When the file 440 is transmitted at time T4, the data E to I are stored in the data storage unit 11 and the data D is deleted, and the cumulative data number Se is “6”.
Indicates that an overflow has occurred because the maximum data number Sh exceeds “5”.

On the other hand, when the receiving device 30 receives the file 430 or the file 440, whether the previous reception of the file 420 was successful (in the case of (a) above),
The process of determining the effective range of the received data differs depending on whether or not it has failed (case (b) above). That is, the serial number Rcp of this time is "2", while the serial number Rcl of the previous time is "2" and the same in the case of (a),
The new data number Rn is a value obtained by subtracting the previous cumulative data number Rel from the current cumulative data number Rep. In the case of (b), the previous serial number Rcl is different by "1",
The new data count Rn is the current cumulative data count Rep itself. Therefore, for file 430, (a)
In the case of, the new data number Rn is “2”, and the last two data G and H of the received data are valid received data,
In the case of (b), the new data number Rn is "5", and all the data D to H of the received data are valid received data.
For the file 440, in the case of (a), the new data number Rn is “3”, and the last three data G to I of the received data are valid received data, and in the case of (b), the new data. Since the number Rn is "6", which is larger than the maximum data number Rh by "1", all the data E to I of the received data are valid received data, and the data loss notification R
A value indicating that one piece of data (data D) is missing is set in m.

As described above, the receiving device 30 can restore all data transmitted from the transmitting device 10 including duplication without duplication, and the transmitting device 10
Even if the data to be transmitted is lost on the side, it can be detected.

[0020]

As described above, according to the data transfer method of the present invention, the transmitting device adds a plurality of data temporarily stored in the data storage unit in the order of occurrence to the cumulative data number and the serial number. Collected in one file and sent to the receiving device via the communication line, the data storage unit is erased and the serial number is incremented only when the confirmation information from the receiving device is received. The serial number and cumulative data number are stored and compared with the serial number and cumulative data number of the file received this time, and the new data number after the last received data is calculated to determine the valid data of this received data. Because
When the file transfer from the sending device to the receiving device fails and the transfer is performed again, it is possible to add the newly generated data up to that point to the contents of the file that failed to transfer, and send it for a certain period of time. When data can be sent only at intervals or when there are few opportunities for transmission, all data can be transferred at the next opportunity, improving communication efficiency and reducing the effect on other communications on the communication line. it can.

In addition, in the unlikely event that the transmitter adds the maximum number of data that can be stored in the data storage means to the file and the receiver detects the difference in the number of new data exceeding the maximum number of data as the number of missing data. Even if the data storage means overflows on the transmitter side and the data disappears, the position and number of the disappeared data can be detected on the receiver side, especially when the previous file was normally received on the receiver side. Despite this, when the data cannot be confirmed by the transmitter and is retransmitted and the overflowed data is already transferred, no loss will occur in the effective received data, so the reliability of data transfer and failure detection capability will not be impaired. Moreover, it is possible to reduce the capacity of the memory that constitutes the data storage means.

[Brief description of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a diagram showing a configuration example of a file used in the present invention.

FIG. 3 is a diagram showing a data restoration operation flow of the receiving apparatus of the embodiment of FIG.

4 is a diagram showing a sequence of data transfer in the embodiment of FIG.

[Explanation of symbols]

 10 Transmitting Device 11 Data Storage Unit 12 Cumulative Data Number Counter 13 Serial Number Counter 14 File Transmission Control Unit 15 Line Interface Unit 20 Communication Network 30 Receiving Device 31 Line Interface Unit 32 File Reception Control Unit 33 Storage Unit 34 Serial Number Comparison Unit 35 Cumulative Data count comparison unit 36 Maximum data count comparison unit 37 Received data restoration unit

Claims (2)

[Claims] 1. A data transfer system in which a plurality of data generated and accumulated at a transmitting device side are collected into one file and are collectively transferred to a receiving device side through a communication line, wherein a plurality of data input to the transmitting device. Data is temporarily stored in the order of input, and a data storage unit that counts the number of stored data as a cumulative number of data; a serial number counting unit that counts a serial number for identifying the contents of the file; File organization means for adding the cumulative number of data and the serial number to the data accumulated in the means to organize the file, and a file organization means connected to the receiving device via the communication line and organized by the file organization means. If the confirmation information indicating the normal reception of the file from the receiving device is received, File transmitting means for erasing transmitted data in the data accumulating means and incrementing the count value of the serial number counting means, wherein the receiving device is connected to the transmitting device via the communication line, and A file receiving unit that receives a file and returns the confirmation information to the transmitting device when the file is normally received, and a file received by the file receiving unit is decomposed into the serial number, the cumulative number of data, and the data, respectively. A file disassembling means to be obtained, a storage means for storing the serial number and the cumulative data number as the previous serial number and the previous cumulative data number each time the file is received, and the current serial number obtained by the file decomposing means. The number and the previous serial number in the storage means are compared to detect if they match. If the serial numbers match, the difference between the current cumulative data number obtained by the file disassembling means and the previous cumulative data number in the storage means is calculated if the serial numbers match. A new data number calculation means for setting the cumulative data number this time as the new data number, and a received data restoration for outputting the data from the final data to the new data number of the data obtained by the file decomposition means as valid data. A data transfer system comprising: 2. The transmitting device, when data exceeds the maximum number of data that can be stored in the data storing means, erases the oldest data while incrementing the count value of the cumulative data. New data is accumulated, the maximum data number is added when the file is organized by the file organization means, and the receiving device obtains the maximum data number from the received file and compares it with the new data number. Is greater than the maximum number of data, the means for outputting a data loss notification indicating the difference between the two as the number of missing data, the received data restoration means is the number of new data and the maximum number of data, whichever is smaller. 2. The data transfer method according to claim 1, wherein the data is output as valid data.