JP2002027010A - Device and method for transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmitting method, with which a file in a large size can be transmitted without lowering line efficiency, and a transmitter using this method. SOLUTION: This device is provided with plural line control parts 15, 16 and 17 for controlling a line, a line table 13 holding time for one of communication corresponding to determined time-out time for each line, a storage means 13, for holding a file to be transmitted through the line, and a control means 11 for dividing and transmitting the file.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a transmission apparatus and a transmission method for transmitting data, and more particularly to a transmission apparatus and a transmission method for transmitting data using a plurality of lines.

[0002]

2. Description of the Related Art A conventional transmission apparatus detects a size of a file to be transmitted in advance, and calculates a transmission time until transmission of the file to be transmitted is completed based on a communication speed of a transmission line. The transmission device starts a timer after starting transmission of the file and detects whether the calculated transmission time has elapsed. If the transmission is not completed after the elapse of the transmission time, the line is disconnected as an error, and processing for retransmitting the file using another line has been performed.

[0003]

However, the conventional transmission apparatus has the following problems.

First, when there is a file of a large size, there is a problem that one line is occupied for a long time.

Second, a communication error (line quality, etc.) can be detected during communication and processing for disconnecting the line can be performed, but cannot be detected during communication (such as a failure of the line control unit itself). Occurs, the transmission processing is continued until the transmission time calculated in advance elapses. For this reason, if a problem that cannot be detected in communication occurs, there is a problem that it is not possible to resend until the communication time is reduced, especially for large files, even if an error occurs There is a problem that retransmission cannot be performed without error processing.

Third, when communication fails, it is difficult to search for the timing of the occurrence of the error after the error processing. Therefore, it is not possible to retransmit only the data of the untransmitted portion of the file, and the transmission fails. Since the entire file needs to be retransmitted, there is a problem that the efficiency of retransmission is low.

The present invention, in order to solve the above-mentioned conventional problems, provides a transmission method capable of transmitting a large file without lowering the line efficiency and a transmission apparatus using the same. The purpose is to:

[0008]

In order to achieve the above object, the present invention comprises a plurality of line controllers for controlling a line,
A line table that holds a timeout time that defines one communication time for each line, a storage unit that holds a file to be transmitted via the line, and a control unit that performs timeout communication of the line table. Prepare.

[0009] With this configuration, even when a file having a large size is transmitted, it is possible to prevent a single line from being occupied for a long time. In addition, since the timeout time is set in advance, even if an abnormality that cannot be detected in communication occurs on the line, the time of the file transmission delay can be reduced.

Further, according to the present invention, a plurality of line control units for controlling lines, a line table for holding a communication speed for each line and a timeout period for determining one communication time in association with each other, Storage means for holding a file to be transmitted; and control means for dividing the file into divided files having a maximum size that can be transmitted within the timeout period of the line and transmitting the divided file via the line.

With such a configuration, even when a large-sized file is transmitted, it is possible to prevent one line from being occupied for a long time. In addition, since a time-out period is set in advance, even if an abnormality that cannot be detected in communication occurs on the line, only the divided file that could not be transmitted need be retransmitted, so that the file transmission delay time can be reduced. Can be.

Further, the present invention provides a line table for holding a plurality of line controllers for controlling lines, a communication time for each line, a timeout time for determining one communication time, and a transmission time for performing communication. A storage unit for holding a file to be transmitted via the line, and dividing the file into a maximum-size divided file that can be transmitted within the transmission time on the line, and transmitting the divided file via the line. Control means.

With such a configuration, even when a file having a large size is transmitted, it is possible to prevent a single line from being occupied for a long time. In addition, since a time-out period is set in advance, even if an abnormality that cannot be detected in communication occurs on the line, only the divided file that could not be transmitted need be retransmitted, so that the file transmission delay time can be reduced. Can be.

In the present invention, the control means sequentially transmits the file using the communicable line.

According to such a configuration, the divided files are transmitted through a communicable line, so that even when a large file is transmitted, one line is not occupied for a long time. You.

In the present invention, the control means adds information indicating that the file is divided to the file name of the divided file.

With this configuration, it is possible to determine whether or not the transmission file has been divided in the transmission device that has received the transmission file, and to perform processing in accordance with the presence or absence of division of the received transmission file. .

Further, the present invention further comprises a receiving means for receiving the divided file, and a combining means for combining the divided files.

With such a configuration, a transmission file composed of divided files can be received and combined into one file.

Further, the present invention provides a step of setting a transmission time in advance for each line, a step of dividing the file into a file size that can be transmitted within the transmission time to generate a divided file, and a step of transmitting the divided file. And a step of performing.

According to such a configuration, even when a large file is transmitted, it is possible to prevent one line from being occupied for a long time. In addition, since the timeout time is set in advance, even if an abnormality that cannot be detected in communication occurs on the line, the time of the file transmission delay can be reduced.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to specific examples shown in the accompanying drawings.

FIG. 1 is a system configuration diagram of a transmission system including a transmission device according to the present invention. 1 is connected to the host computer 1 on the transmission side, and transmits transmission data from the host computer 1 via the first line 5, the second line 6, and the third line 7 to the reception side. Transmit to device 3. The receiving-side transmission device 3 is connected to the receiving-side host computer 4 and transmits the transmission-side transmitting device 2 transmitted via the first line 5, the second line 6, and the third line 7.
And transfers the data to the host computer 4 on the receiving side. In FIG. 1, the transmission devices 2 and 3 and the host computers 1 and 4 are illustrated as one receiving side and the other as a transmitting side. However, transmission data may be transmitted using one as a transmitting side and the other as a receiving side. it can.

FIG. 2 is a hardware block diagram of a transmission device according to the present invention. The main controller 11 is a part that controls the entire transmission device, and executes the data transmission processing of the present invention. The host interface unit 12 is connected to the host computer 1 or 2 in FIG. 1 and exchanges transmission data from the host computer and reception data to the host computer. The RAM unit 13 is a unit that stores transmission data and reception data. This RAM
The section 13 is further provided with an area for storing a line table R (FIG. 3) and a transmission job (JOB) table (FIG. 8) described later. The ROM section 14 is a section for storing the processing program of the present invention executed by the main control section 11. The first line control unit 15 corresponds to the first line 5 in FIG. 1, and the second line control unit 16 corresponds to the second line 6 in FIG.
The third line control unit 17 is connected to the third line 7 in FIG. 1 and transmits transmission data via the corresponding line and receives data received from the corresponding line.

FIG. 3 shows lines (first line 5, second line 5 in FIG. 1) used in the transmission system including the transmission device according to the present invention.
It is a schematic diagram of a line table of a line 6 and a third line 7). In FIG. 3, the line speed (Kbit / s) of each line, 1
Timeout time (minutes), which is the upper limit of the communication time of communication, transmission time (minutes) indicating the actual transmission time, and transmission indicating the amount of data transmitted within the transmission time at the line speed of each line The data amount (KB) is shown. The line table of the present invention stores a line speed, a timeout time, and a transmission time. In FIG.
For clarity of description, the transmission data amount of each line is described for reference, but this transmission data amount is obtained by multiplying the line speed by the transmission time.

FIG. 4 shows a transmission flowchart of the transmission apparatus according to the present invention. Transmission processing is started in step 4010 of FIG. In step 4015, the file to be transmitted is registered as a file to be transmitted. Step 4
In 020, it is determined whether or not there is a transmission target file. If there is, the process proceeds to step 4040, and if not, the process proceeds to step 4030.

If it is determined in step 4020 that there is a file to be transmitted, and the flow advances to step 4040, the first file in FIG.
It is determined whether there is a line that can be transmitted among the line 5, the second line 6, and the third line 7.
Go to 50. If there is no line that can be transmitted, the process enters a standby state.
Go to 50.

In step 4050, it is determined whether or not the transmission target file needs to be divided and transmitted. This determination is performed as follows. First, the transmission data amount of the transmittable line is obtained by multiplying the line speed in the line table of FIG. 3 by the transmission time. Next, the transmission data amount of the line having the largest transmission data amount among the lines that can be transmitted next is compared with the size of the transmission target file. If the transmission data amount of the line with the maximum transmission data amount is equal to or larger than the size of the transmission target file, it is determined that file division is not necessary. If the transmission data amount of the line with the maximum transmission data amount is smaller than the size of the transmission target file, it is determined that the file needs to be divided.

If it is determined in step 4050 that file division is necessary, the flow advances to step 4060 to transmit a divided file. If it is determined in step 4050 that file division is not necessary, the flow advances to step 4070 to transmit the transmission target file through one line.

The transmission processing of the divided file in step 4060 is performed according to the divided file transmission flow of FIG. 10 described later. The file transmission processing of step 4070 is performed according to the file transmission flow of FIG. 9 described later.

When step 4060 or step 4070 is completed, the process proceeds to step 4020. Step 4 below
Steps 4020-4040-4050-4060 (40) until it is determined in 020 that there is no transmission target file.
70) The loop of -4020 is repeated.

If it is determined in step 4020 that there is no file to be transmitted, the flow advances to step 4030 to end the transmission processing.

Next, the file transmission processing in step 4070 of FIG. 4 will be described with reference to FIGS. 9 and 11.

As shown in FIG. 11, it is assumed that the size of the original file is 61400 Kbytes, and the line having the maximum amount of transmission data that can be transmitted in step 4050 of FIG. 4 is the first line 5 (line No. 1). . Therefore, in step 4050 of FIG. 4, it is determined that file division is not necessary, and the process proceeds to step 4070.
The processing procedure jumps to 10 and proceeds.

When the process is started in step 9010 of FIG. 9, file transmission is started in step 9020.
In the example of FIG. 11, the entire transmission target file is transmitted via the first line 5.

In step 9030, the first line 5 in FIG.
The process waits for the elapse of 10 minutes, which is the timeout time of (line No. 1). In Step 9040, it is determined whether or not the transmission file has been successfully transmitted. If it is determined that the transmission file has not been successfully transmitted, Step 9020 is performed.
To step 9040 until it is successfully transmitted.
The loop of -9020-9030-9040 is repeated.

If it is determined in step 9040 that the file was successfully transmitted, the flow advances to step 9050 to delete the transmitted file from the registration of the file to be transmitted. Step 9
In step 060, the process returns when step 4070 in FIG. 4 ends.

When the process in step 4070 of FIG. 4 is completed, the flow advances to step 4020. In the base 4020,
The presence or absence of the transmission target file is determined, and in the example of FIG.
Since the entire transmission file has been deleted from the registration of the transmission target file in step 9050 in FIG.
Proceeding to 30, the file transmission process ends. In this way, if the original file is similar to the example in FIG.
Times of file transmission (hereinafter "1 cycle file transmission")
That. ) Sends the entire file.

Next, the divided file transmission processing in step 4060 of FIG. 4 will be described with reference to FIGS.

As shown in FIG. 6, the size of the original file is 108544 KBytes, and the lines that can be transmitted are all of the first line 5, the second line 6 and the third line 7, and the step 4050 in FIG. Is assumed to be the first line 5 (line No1) with the maximum amount of transmission data that can be transmitted. Therefore, in step 4050 of FIG. 4, it is determined that file division is necessary, and the process proceeds to step 4060.

In step 4060 of FIG. 4, the processing procedure jumps to step 10010 of FIG. When the process is started in step 10010 of FIG.
At 0020, file division is performed. As shown in FIG. 6, the size of the original file (108544 KByte)
Is the total transmission data amount of the transmittable line (10854
4KByte), the original file is divided into divided files having a data amount corresponding to a line that can be transmitted.

At this time, each of the divided files is given a division number according to the nomenclature shown in FIG. In the example of FIG. 12, the division number “1” is added to the division file transmitted through the first line 5 (line No. 1), and the second line 6 (line N
The division file “2” is assigned to the division file transmitted via o2), and the division number “end” is assigned to the division file transmitted via the third line 7 (line No. 3). Each divided file thus generated is stored in the RAM shown in FIG.
Stored in the unit 13.

In step 10030, all of the divided files are registered as transmission target files. In the example of FIG. 6, the divided files having the division numbers “1”, “2”, and “end” are registered as transmission target files. Step 1
In 0035, the registration of the divided original file as the transmission target file is deleted.

In step 10040, the transmitted divided file is registered as a transmitted divided file. In the example of FIG. 6, the divided files having the division numbers “1”, “2”, and “end” are registered as transmission division files.

In step 10050, it is determined whether there is a file registered as a transmission division file, and if there is a transmission division file, the flow proceeds to step 10060, and
If there is no transmission division file, the flow advances to step 10090.

When it is determined in step 10050 that there is a transmission division file, and the flow advances to step 10060, the transmission division file is transmitted. In the example of FIG. 6, the division number “1”,
The divided files “2” and “end” are transmitted from the first line control unit 15, the second line control unit 16, and the third line control unit 17 in FIG. 2, respectively.

In step 10070, the process waits until the timeout time has elapsed for all the lines used for transmission, and proceeds to step 10080 when the timeout time has elapsed.

During the waiting state until the timeout time in step 10070 elapses, the transmission job table shown in FIG. 8 is provided in the area of the RAM unit 13 in FIG. ing. The line status column in FIG. 8 indicates whether or not each line is transmitting.
The column of transmission elapsed time indicates the time elapsed since the transmission of each line was started, and the column of transmission file indicates the file name of the divided file being transmitted on each line. The file size column indicates the file size of the divided file transmitted on each line. Step 10070
Then, the timeout time of each line in FIG. 3 is compared with the transmission elapsed time of each line in FIG. 8, and when the transmission elapsed time becomes longer than the timeout time in all the lines, the process exits the standby state and proceeds to step 10080. .

In step 10080, it is checked whether or not the divided file has been successfully transmitted, and the successfully transmitted divided file is deleted from the registration of the transmitted divided file. When step 10080 is completed, step 1005
The process proceeds to 0, and it is determined whether there is a transmission division file. Until it is determined in step 10050 that there is no transmission division file, steps 10050-10060-1007 are performed.
The loop of 0-10080-10050 is repeated.
In the example of FIG. 6, the division numbers “1”, “2”, and “end”
This loop is repeated until all the divided files are successfully transmitted.

If it is determined in step 10050 that there is no transmission division file, the flow advances to step 10090 to delete the transmitted division file from the registration of the transmission target file. In the example of FIG. 6, the division numbers “1”, “2”, and “e”
The “nd” divided file is deleted from the registration of the transmission target file, and the registered file disappears.

In step 10100, step 4 in FIG.
060 is completed, and the process returns to step 4 in FIG.
From 060, the process proceeds to step 4020. Step 4020
Then, since there is no registered file, step 4
Proceeding to 030, the transmission process ends.

Next, the divided file transmission processing in step 4060 in FIG. 4 will be described with reference to FIGS. 10 and 12.

As shown in FIG. 12, the size of the original file is 169984 KBytes, and in step 4040 of FIG.
All of the line 6 and the third line 7, and
It is assumed that the line having the maximum transmittable data amount at 050 is the first line 5 (line No1). Therefore, in step 4050 of FIG. 4, it is determined that file division is necessary, and the process proceeds to step 4060.

In step 4060 of FIG. 4, the processing procedure jumps to step 10010 of FIG. When the process is started in step 10010 of FIG.
At 0020, file division is performed. As shown in FIG. 12, the size of the original file (169998 bytes)
Is the total transmission data amount of the transmittable line (10854
If the size of the original file is larger than 4 KB, the original file is divided into a divided file having a data amount corresponding to a transmittable line and a file having the remaining data amount. At this time, a division number is assigned to each of the divided files according to the nomenclature shown in FIG. In the example of FIG. 12, the first line 5 (line No. 1)
File (61440 KB) transmitted via
In e), the division number "1" is stored in the second line 6 (line No. 2).
File (46080Kbyte) transmitted via
In e), the division number “2” is stored in the third line 7 (line No. 3).
File (1024KB) transmitted via
Has a division number “3” in the remaining files (61440)
Is assigned a division number “end”. Each divided file generated in this way is stored in the RAM unit 13 in FIG.

In step 10030, all of the divided files are registered as transmission target files. In the example of FIG. 12, the division numbers “1”, “2”, “3”, and “end”
Are registered as transmission target files.
In step 10035, the registration of the divided original file as the transmission target file is deleted.

In step 10040, the transmitted divided file is registered as a transmitted divided file. In the example of FIG. 12, the divided files having the division numbers “1”, “2”, and “3” are registered as transmission division files.

In step 10050, it is determined whether there is a file registered as a transmission division file, and if there is a transmission division file, the flow advances to step 10060, and
If there is no transmission division file, the flow advances to step 10090.

When it is determined in step 10050 that there is a transmission division file, and the flow advances to step 10060, the transmission division file is transmitted. In the example of FIG. 12, the divided files of the division numbers “1”, “2”, and “3” are respectively the first line control unit 15, the second line control unit 16, and the third line control unit 16 of FIG.
It is transmitted from the line control unit 17.

In step 10070, the process waits until the timeout time elapses for each line used for transmission.
Proceed to 0080.

In step 10080, it is checked whether or not the divided file has been successfully transmitted, and the successfully transmitted divided file is deleted from the registration of the transmitted divided file. When step 10080 is completed, step 1005
The process proceeds to 0, and it is determined whether there is a transmission division file. Until it is determined in step 10050 that there is no transmission division file, steps 10050-10060-1007 are performed.
The loop of 0-10080-10050 is repeated.
In the example of FIG. 12, this loop is repeated until all the divided files of the division numbers “1”, “2”, and “3” are successfully transmitted.

If all the transmission division files have been transmitted successfully, it is determined in step 10050 that there is no transmission division file, and the flow advances to step 10090. Step 10
At 090, the transmitted divided file is deleted from the registration of the transmission target file. In the example of FIG. 12, a state in which the divided files with the division numbers “1”, “2”, and “3” are deleted from the registration of the transmission target file, and only the division file with the division number “end” is registered in the transmission target file Becomes

In step 10100, the process returns when step 4060 in FIG. 4 ends. Returning to the point in time when step 4060 in FIG.
Go to 020. At this point, one cycle of transmission has been completed.

In step 4020 of FIG. 4, it is determined whether there is a file to be transmitted. In the example of FIG. 12, since the divided file with the division number “end” is registered in the transmission target file, steps 4020 to 4040
Proceed to. At this point, the file transmission process in the second cycle starts.

In step 4040, when there is a line that can be transmitted, the process proceeds to step 4050.

At step 4050, it is determined whether file division is necessary. In the example of FIG. 12, the division number "e
nd "is 61440 KByte
Therefore, when the first line 5 can be transmitted, the transmission is performed by the first line 5, so that file division is not necessary, and the process proceeds to step 4070. FIG. 12 shows a division number “end”
Is illustrated as being transmitted by the first line 5 without being divided, but the first line 5 cannot be transmitted, and either or both of the second line 6 and the third line 7 are not transmitted. If transmission is possible, the process proceeds from step 4050 to step 4060, where the divided file (file size 61400 KBe) with the division number "end" is further divided into the division files with the division number "4" and the division number "end". In this case, if the divided file with the division number “4” is transmitted through the second line 6, the size of the division file with the division number “4” is 46080 KByte.
e, the size of the divided file with the division number “end” is 15
It becomes 360 KB. If the divided file of the division number “4” is transmitted by the third line 7, the size of the division file of the division number “4” is 1024 KBy.
te, the size of the division file with division number "end" is 6
0416 KB.

At step 4050, it is determined that division is not necessary (when the first line 5 can be transmitted), and
After the divided file (file size 61400 KBe) of the division number “end” is transmitted in step 070, the division file of the division number “end” is deleted from the registration of the transmission target file in step 9050 of FIG. 9, and step 4070 of FIG. To step 4020. Step 402
In the case of 0, since there is no transmission target file, step 4030
And the transmission process ends.

When division is required in step 4050 of FIG. 4 and the second line 6 and the third line 7 can be transmitted,
In step 10020 of 0, the divided file with the division number “end” (file size 61400 KB) is divided into the divided file with the division number “4” (file size 46080 KB) and the divided file with the division number “end” (file size 15360 KB). In step 10030, the division number “4” (file size 46
080 KByte) divided file and division number “en
d "divided file (file size 15360 KBy
te) is registered as a transmission target file, and step 1
The original division number “e” which is the file divided in 0035
nd "divided file (file size 61400 KB
The registration as the transmission target file of “ye)” is deleted, and the division file of the division number “4” and the division file of the division number “end” are transmitted by the processing of FIG. 10, and in step 10090 of FIG. 4 is deleted from the registration of the transmission target file, and the divided file with the division number “end” is deleted from the registration of the transmission target file.
From 060, the process proceeds to step 4020. Step 4030
Then, since there is no transmission target file, the process proceeds to step 4030, and the transmission process ends.

If division is required in step 4050 in FIG. 4 and only the second line 6 can be transmitted, in step 10020 in FIG. 10, the division file (file size 61400 KBe) having the division number “end” is added to the division number “ 4 "
The file is divided into a divided file having a file size of 1024 KBytes and a divided file having a division number “end” (file size 60416 KBytes).
0 and the division number “4” (file size 1024 KB)
The divided file of e) and the divided file (file size 60416 KByte) of the division number “end” are registered as transmission target files, and the divided file of the original division number “end” (file size 61400 KBe) which is the file divided in step 10035 ) Is deleted from the registration of the transmission target file, and only the division file of the division number “4” is transmitted by the processing of FIG.
In step 10090 of FIG. 10, the division file with the division number “4” is deleted from the registration of the transmission target file, and the division file with the division number “end” (file size 6041)
6 KB) is registered in the transmission target file. Subsequently, the process proceeds from step 4060 in FIG. 4 to step 4020, where the presence or absence of the transmission target file is determined, and there is a divided file (file size 60416 KBytes) of the division number “end”.
Proceeding to 40, the transmission process in the third cycle is started. Hereinafter, steps 4020-4040-40 until it is determined in step 4020 of FIG. 4 that there is no file to be transmitted.
50-4060 (4070) -4020 are repeated.

FIG. 8 shows a transmission job (JOB) table used when transmitting a file by the transmission apparatus according to the present invention. This transmission job table indicates the transmission status of each line, the line status indicates whether or not transmission is in progress, the transmission elapsed time indicates the elapsed time since the start of transmission, and the transmission file indicates The file name indicates the file name transmitted on the line, and the file size indicates the size of the file in which the file name is indicated. In step 9030 of FIG. 9 and step 10070 of FIG. 10, it is determined whether the timeout time has elapsed by comparing the transmission elapsed time of FIG. 8 with the timeout time of FIG.

Next, the processing procedure of file reception by the transmission device according to the present invention will be described. FIG. 5 shows a flowchart of the file reception processing procedure. In step 5020 of FIG. 5, the file reception process is started.
At 020, it is determined whether or not there is a received file whose transmission has been started. In step 5020, the process is in a standby state while there is no received file transmitted, and when a received file is received, the process proceeds to step 5030.

In step 5030, a file is received. In step 5040, it is determined whether the received file has been successfully received. If the signal has been successfully received, the process proceeds to step 5050. If the signal has not been successfully received, the process proceeds to step 5030, and the loop of steps 5040-5030-5040 is repeated until the signal is successfully received.

When the process proceeds from step 5040 to step 5050, it is determined whether or not the received file is a divided file. In this determination, if the division number shown in FIG. 7 is not added to the file name of the reception file, it is determined that the reception file is not a division file, and if the division number is added, the reception file is a division file. Is determined.

If it is determined in step 5030 that the file is not a divided file, the process proceeds to step 5090. If it is determined that the file is a divided file, the process proceeds to step 5060.

At step 5060, it is determined whether or not all of the divided files have been successfully received. If the received files have been successfully received, the process proceeds to step 5080.

If it is determined in step 5060 that there is a divided file that has not been properly received, step 5
070, the file is received, and then step 50
Proceed to 60. After that, until all divided files are successfully received. The loop of steps 5060-5070-5060 is repeated.

In step 5080, a process of combining the received divided files is performed. In step 5090, the received file is transmitted from the transmission device 3 on the reception side to the host computer 4 on the reception side in FIG.

In the embodiment described above, the transmission time of each line is fixed as shown in FIG. 3, but when the original file is divided and transmitted, all divided files can be transmitted in one cycle of transmission. Then, the transmission time of each line may be changed so that the total amount of transmission data of each line becomes equal to the data amount of the original file.

In this case, the transmitting side and the receiving side have a one-to-one correspondence.
Although the explanation was made using the line connected by, this line is TCP / IP
A LAN line having such a protocol may be used. LAN
When lines are used, the file is divided and the files are transferred to each line, as in the present embodiment. Also,
As a protocol for performing the transfer, a protocol capable of file transfer such as FTP, HTTP, and SMTP is used.

Further, in the case of a LAN line, not only a timeout period is set, but also an LA for transmitting a file.
The bandwidth on the N line may be narrowed. For example, by setting the line transmission speed to 20% (this can be arbitrarily set by the user), the LAN line becomes full for file transfer, and communication other than file transfer cannot be performed. Can be prevented. Further, since one large file is distributed and transmitted over a plurality of LAN lines, traffic on the LAN line can be distributed.

[0080]

According to the present invention, a timeout period is set in advance, and a file is divided and transmitted. Therefore, even when a large file is transmitted, one line is occupied for a long time. Is eliminated.

Further, since the timeout time is set in advance, even if an abnormality that cannot be detected in communication occurs on the line, the time of file transmission delay can be reduced.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a transmission system including a transmission device according to the present invention.

FIG. 2 is a hardware block diagram of a transmission device according to the present invention.

FIG. 3 is a schematic diagram of a line table.

FIG. 4 is a transmission flowchart of a transmission device according to the present invention.

FIG. 5 is a reception flowchart of the transmission device according to the present invention.

FIG. 6 is a configuration diagram of a divided file.

FIG. 7 is a configuration diagram of a divided file name.

FIG. 8 is a configuration diagram of a transmission job table.

FIG. 9 is a flowchart of a processing procedure for transmitting a file without dividing the file.

FIG. 10 is a flowchart of a processing procedure for dividing a file and transmitting the file.

FIG. 11 is a diagram showing a file configuration when a file is transmitted without dividing the file.

FIG. 12 is a diagram illustrating a file configuration in a case where a file is divided and file transmission is performed in two cycles

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sending host computer 2 Sending side transmitting device 3 Receiving side transmitting device 4 Receiving side host computer 5 1st line (line No1) 6 2nd line (line No2) 7 3rd line (line No3) 11 Main control unit 12 host Interface unit 13 RAM unit 14 ROM unit 15 First line control unit 16 Second line control unit 17 Third line control unit

Claims (7)

[Claims] 1. A line table for holding a plurality of line controllers for controlling a line, a time-out time corresponding to one line for each line, and a storage for holding a file to be transmitted via the line. And a control unit for performing communication for a timeout period of the line table. 2. A line table for holding a plurality of line controllers for controlling lines, a communication speed for each line and a time-out period for determining one communication time, and a file transmitted through the line. And transmission means for dividing the file into divided files of a size that can be transmitted within the timeout period of the line and transmitting the divided file via the line. apparatus. 3. A line table for controlling a plurality of line controllers for controlling lines, a line table for holding a communication time for each line, a timeout period for determining one communication time, and a transmission time for performing communication, and A storage unit for holding a file to be transmitted via the transmission line, and a control unit for dividing the file into divided files having the maximum size that can be transmitted within the transmission time on the line and transmitting the divided file via the line. A transmission device comprising: 4. The transmission apparatus according to claim 1, wherein the control unit transmits the file sequentially using the communicable line. 5. The transmission apparatus according to claim 2, wherein the control unit adds information indicating that the file is divided to the file name of the divided file. 6. The transmission apparatus according to claim 2, further comprising: a receiving unit that receives the divided file; and a combining unit that combines the divided files. 7. A transmission method for transmitting a file, comprising:
Setting a transmission time in advance for each line, dividing the file into a file size that can be transmitted within the transmission time to generate a divided file, and transmitting the divided file. Characteristic transmission method.