JPH08153054A - File transfer system - Google Patents

Abstract

PURPOSE: To provide a means enhancing the efficiency of file transfer between server and client and to make this efficiency enhancing means to apply to file transfer between spots with a time difference. CONSTITUTION: A client 10 is provided with a final transfer date table 11 of the date receiving the transfer of a file 12 and a means sending back the file name and the final transfer date by pairing at the time of a file transfer request. The server 20 is provided with an update date table of the date updating a file 22 and a means comparing an update date and a final transfer date at the time of receiving the file transfer request and processing a transfer request. Besides, in order to slove the problem on the time difference, the client 10 is provided with a table holding the time difference between the client and the server 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file transfer method between computers via a network,
In particular, it relates to a method of efficiently transferring only files that need to be transferred.

[0002]

2. Description of the Related Art FIG.
It is a figure which shows the structure of the file transfer system disclosed by the publication. In FIG. 23, a file providing computer (hereinafter, referred to as a server) 110 that provides files is connected to a file provided computer (hereinafter, referred to as a client) 130 that receives a plurality of files via a network 120. ing. Also, the server 110
Is a file group 111 and updates about this file group,
The file management list 112 that manages the last update date and the like is provided, and the client 130 is provided with the file group 131 that was previously transferred and the last transfer date file 132 that was last transferred regarding this file group 131.

The operation of the file transfer system configured as described above will be described below with reference to the drawings. First, the client 130 requests the transfer of the file management list 112 of the server 110 from the server 110 prior to the file transfer request. Next, the client 130 receives the transferred file management list 112.
Referring to, a file transfer request is made to the server 110 for a file updated after the date registered in its own final transfer date file 132. In response to this file transfer request, the server 110 transfers the requested file to the client 130.

[0004]

In the conventional file transfer system configured as described above, the client 1
Since the server 30 first needs to have the file transfer list 112 transferred from the server before requesting the transfer of the necessary files, the cost of transferring the file management list 112 itself ( There was a problem that the transfer time) was long.

There is also a problem that the file management list 112 needs to be transferred even when transferring a file not registered in the file management list 112 or only one file.

Further, the server 112 and the client 13
If a time difference occurs because 0 is far away,
Generally, both of them operate in the time of their own system, so it becomes meaningless to check the files updated after the last transfer date by using the time, and the above method is used. There was a problem that it could not be used.

The present invention has been made in order to solve the above-mentioned problems, and it is necessary to transfer the file management list without transferring it by checking the date of the requested file on the server side. It is an object of the present invention to provide a file transfer method capable of efficiently transferring only secure files.

Further, even when the distance between the server and the client is long and a time difference occurs, the client operator can efficiently transfer only the necessary files without being aware of the problem of the time difference. The purpose is to

It is another object of the present invention to allow transfer requests for a plurality of files to be designated at a time so that a plurality of files can be transferred with a single transfer request.

Further, when file transfer is required, it is another object of the present invention to make the transfer more efficient.

[0011]

A file transfer system according to a first invention is a system in which a file supply device for supplying a file and a file supply device for receiving a file from the file supply device are combined,
The first table having the latest transfer date, which is the latest date of the file in the own device, and the first table when requesting the file transfer device to transfer the file, are searched for and obtained. And a transmission request means for transmitting a transfer request message in which the file name and the first data, which is the date based on the final transfer date, are transmitted, and the file update device updates the file in the device itself. A second table having a date, second data based on an update date obtained by searching the second table, and a first data
And a response transmitting means for transmitting a response message in which the requested file name and the processing result are paired with each other, and processes the file only when the second data has a newer date. It is intended to be transferred.

A file transfer system according to the second invention is
The last transfer date, which is the latest date of the transferred file, is used as the first data, and the update date is used as the second data.

The file transfer system according to the third invention is
The file supplied device is provided with a third table in which the time difference between its own device and the file supply device is registered, and the time difference obtained by searching the third table as the first data and the first table are searched. The calculated value of the final transfer date obtained is
The update date is used as the second data.

The file transfer system according to the fourth invention is
The file supply device is provided with a fourth table in which the time difference between the device itself and the file supply device is registered, and the last transfer date, which is the latest date of the transferred file, is used as the first data, and the second data is used. As the above, the date obtained by calculating the time difference obtained by searching the fourth table and the update date obtained by searching the second table is used.

A file transfer system according to the fifth invention is
In a system that combines a file supply device that supplies a file and a file supply device that receives the file from this file supply device, the file in the device itself and the latest date when this file was transferred to the file supply device A first table having a final transfer date that is, and a first table when requesting a file from a file supply device.
Requesting means for obtaining the difference between the last transfer date and the current time of the device itself as a first difference, and transmitting the transfer request message by pairing the first difference and the file name. And a second table having the latest update date for updating the file in the own device, and a difference between the update date obtained by searching the second table and the current time of the own device. Is obtained as a second difference, and this is compared with the first difference to be processed, and an answer sending means for sending an answer message in which the requested file name and its processing result are paired is provided. The file is transferred only when the difference of 1 is larger.

A file transfer system according to the sixth invention is
The transmission request means creates a transfer request message including a plurality of pairs of a file name and its first data,
The reply sending means is configured to process this transfer request message and send a reply message consisting of a plurality of pairs of file names and their processing results.

The file transfer system according to the seventh invention is
The file is processed as a virtual file configured as a group of one or more files.

A file transfer system according to the eighth invention is
The reply sending means is provided with a means for adding a header to the reply message and transmitting the file following the header.

[0019]

In the file transfer system according to the first aspect of the invention, when the file-supplied device makes a file transfer request, the transmission request means searches the first table to obtain the final transfer date of the file. , A message in which the first data relating to the date obtained based on this final transfer date is paired with the file name is transmitted as a file transfer request. In the file supply device that receives this, the response requesting means compares the second data based on the update date obtained by searching the second table of the own device with the received first date. , Transfer the file only when the second data is newer.

In the file transfer method according to the second aspect of the invention, the transmission request means of the file-supplied device transmits the final transfer date obtained by searching the first table as a pair with the file name. In the file supply device, the answer transmission means compares the update date obtained by searching the second table with the last transfer date received, and transfers the file only when the update date is newer.

In the file transfer method according to the third aspect of the invention, the transmission request means of the file-supplied device searches the third table for the final transfer date obtained by searching the first table and supplies the file obtained by searching the third table. A value obtained by calculating the time difference with the device is transmitted as the first data. In the file supplied device,
The answer sending means compares the update date obtained by searching the second table with the received first data, and transfers the file only when the update date is newer.

In the file transfer method according to the fourth aspect of the present invention, the transmission request means of the file-supplied device transmits the final transfer date obtained by searching the first table as the first data. The file supply device compares the calculated time difference with the supplied device obtained by searching the fourth table and the update date obtained by searching the second table with the received first data. And transfer the file only when the update date is newer.

In the file transfer system according to the fifth aspect of the invention, the transmission request means of the file-supplied device searches for the difference between the final transfer date obtained by searching the first table and the current time of the device itself. Is calculated as a difference and is transmitted as a pair with the file name. In the file-supplied device, the difference between the update date obtained by searching the second table by the answer sending means and the current time of the device itself is obtained as a second difference, and this difference is compared with the first difference, Send the file only when the first difference is greater.

In the file transfer system according to the sixth aspect of the present invention, the transmission request means of the file-supplied device generates a plurality of pairs of file names and their first data and transmits them as a transmission request message. In the file-supplied device, the message received by the reply transmission means is processed, and a plurality of pairs of each file and the processing result are generated and responded.

In the file transfer system according to the seventh aspect of the present invention, one or more files are grouped together in both the file-supplied device and the file supply device, the group is treated as a virtual file, and the file transfer is performed as a virtual file. Do in units.

In the file transfer system according to the eighth aspect of the present invention, the reply transmission means of the file supply device provides a header for the reply data of the file transmission request, and when it is necessary to transmit the file, this file is followed by the header. Send the file itself.

[0027]

【Example】

Example 1. FIG. 1 is a block diagram showing an embodiment of a file transfer system according to the present invention. In the figure, 10 is a client that receives the supply of a file from the server 20 on the file supply side, and the plurality of clients 10 and the plurality of servers 20 are connected by a network. Further, the server 20 includes a file group 22 and an update date table 21 in which the dates when each file in the file group is updated are files. The client 10 includes the file group 12 and each file in the file group 12 lastly. A final transfer date table 11 in which the transferred dates are stored in a file is provided.

FIG. 2 and FIG. 3 are views showing the format of the message used at the time of file transfer in this embodiment. FIG. 2 is the format of the message when the client 10 requests the server 20 for file transfer. The name and the date the file was last transferred are set. FIG. 3 shows the format of a message when the server 20 responds to the file transfer request from the client 10, and the file name and the processing result are set.

FIGS. 4 and 5 are diagrams showing an example of the file update date table 21a and the file final transfer date table 11a in this embodiment. FIG. 4 shows the update when the server 20 updates the file group 22. The update date table 21a, which is a file to be stored, has a file name and date and time. Also,
FIG. 5 is a final transfer date table 11a which is a file in which the client 10 updates the file transferred from the server 20, and has a file name and the date and time when the file was last transferred.

FIGS. 6 and 7 are flowcharts for explaining the operation of the server 20 and the client 10 in this embodiment, respectively. FIG. 6 is a diagram for explaining the operation of the client 10 and FIG. 7 is a diagram for explaining the operation of the server 20. .

The operation of this embodiment will be described below with reference to the drawings. First, the client 10 transmits a file transfer request to the server 20 when a file is needed (step S601). At this time, the client 10 searches the final transfer date table 11a for the name of the file that needs to be transferred and the final transfer date, creates a message in the format shown in FIG. When the server 20 receives the message as a file transfer request (step S701), the server 20 searches the update date table 21 to determine whether the requested file exists in its own system (step S702). If the requested file does not exist in the server 20 as a result of the search, a message that sets the processing result of the format shown in FIG. 3 to "no file" is created and a response to the file transfer request is sent to the client 10 (step S704). ).

If the requested file exists in its own system, the server 20 searches the update date table 21 for the update date of this file (step S7).
03). The update date obtained by searching is compared with the final transfer date shown in the message at the time of file transfer request, and it is judged whether the update date is newer than the final transfer date (step S705), and the update date is newer. In this case, a message with the processing result of the format shown in FIG. 4 as "transfer" is created and sent to the client 10 as a response to the file transfer request (step S706).
If the update date is not later than the last transfer date, a message that makes the processing result of the format shown in FIG. 4 "unnecessary" is created and sent to the client 10 as a response to the file transfer request (step S70).
8). After that, when the processing result is transfer, the corresponding file is transmitted (step S707).

On the other hand, the client 10 receives the response to the file transfer request (step S602) and checks the portion of the processing result (step S603). If the processing result is "transfer", the process proceeds to the file receiving process (step S604). After receiving the file,
The final transfer date of the final transfer date table 11a is updated (step S605). If there are further files to be transferred, the above operation is repeated.

As described above, according to this embodiment, since it is not necessary to transfer the file directory prior to the file transfer as described in the conventional example, the file transfer can be efficiently carried out.

In the above embodiment, the year, month, day, hour, and minute are used as the date, but the year, month, year, month, day,
You can also use year / month / day, year / month / day / hour / minute / second. Furthermore, the example in which the file update date table 21a is created in the system (server 20) is shown, but if the operating system of the system implementing the present invention has a function of managing the file update date, May be used. This also applies to the following examples.

Example 2. 8 to 11 are views for explaining another embodiment of the present invention. 8 and 9 are diagrams showing a format of a message used at the time of file transfer in this embodiment, and FIG. 8 shows a format of a message when a file transfer is requested from the client 10 to the server 20, the file name and its Multiple pairs with the date when the file was last transferred are set. FIG. 9 is a diagram showing a format of a message when the server 20 responds to a file transfer request from the client 10, and there are a plurality of pairs of a file name and a processing result (a plurality of pairs indicated by a message from the client 10). (Corresponding to the number of pairs) is set.

FIGS. 10 and 11 are flowcharts for explaining the operation of the server 20 and the client 10 in this embodiment. FIG. 10 shows the operation of the client 10 and FIG.
FIG. 1 is a diagram illustrating the operation of the server 20.

The operation of this embodiment will be described below with reference to the drawings. Note that FIG. 1, which is the same as that of the first embodiment, is used as the configuration diagram showing the file transfer method in this embodiment. Also, as the format of file history management of the server 20 and the client 10, the same FIG. 4 and FIG. 5 as in the first embodiment are used.

When a plurality of files are required, the client 10 sends a file transfer request to the server 20 (step S1401). At this time, the client 10 searches the final transfer date table 11a, obtains the required number of pairs of the file name of the transfer request and the final transfer date, and obtains the required number of pairs.
Create a message in the format
(Step S1401). The server 20 receives this file transfer request (step S1501).
Then, the update date table 21a is searched to see if each requested file exists in the system (step S1502).
As a result of the search, for a file that does not exist among the files requested by the server 20, a message indicating that the processing result in the format as shown in FIG. 9 is "no file" is created, and the client responds to the file transfer request. 10 (step S1503).

On the other hand, for an existing file of the requested files, the update date of this file is obtained by searching the update date table 21a (step S1504).
The update date obtained by the search is compared with the final transfer date indicated in the message at the time of requesting the file transfer, and it is determined whether the update date is newer than the final transfer date (step S1505). For a file newer than the transfer date, a message with the processing result of the format shown in FIG. 9 as "transfer" is created and transmitted as a response to the file transfer request from the client 10 (step S1507). Also, for files whose update date is not later than the last transfer date,
A message that makes the processing result of the format shown in FIG. 9 "unnecessary" is created and transferred to the client 10 as a response to the file transfer request (step S150).
6). After that, it is checked by the received message whether or not the file for which the file transfer is requested remains (step S1508). If it remains, the process is repeated from step S1502. When the above processing is completed for all requested files, the reply to the file transfer request is transmitted to the client (step S15).
09). Next, for a file whose processing result is transfer, the file is transmitted (step S1510).

The client 10 receives the reply to the file transfer request (step S1402) and checks the portion of the processing result (step S1403). If the processing result is "transfer", the process proceeds to the file receiving process (step S1404). When the file has been received, the final transfer date of the final transfer date table 11a is updated (step S1405). Then, the process proceeds to file transfer response analysis processing. When the processing result is not "transfer", the process moves to the file transfer reply analysis process when the reply to the transfer request is received. In the file transfer answer analysis process, it is checked whether there is a new file process result (step S
1406). If it is the end of the file transfer reply, the process is completed. If there is a new file processing result, the process is repeated from step S1403.

As described above, according to this embodiment, transfer requests for a plurality of files can be designated at one time, so that the efficiency of file transfer is improved. In this embodiment, the format of the file transfer request is shown in FIG.
Although FIG. 9 is used as the file transfer response format, a header section may be provided at the beginning and the number of files, the total length, etc. may be set there.

Example 3. 12 and 13 are views for explaining still another embodiment according to the present invention. In FIG. 12, 21b is an update date table 2 in the first embodiment.
In the update date table 21b in this embodiment, which corresponds to 1a, one or more files used in the same job or the like are defined as virtual files (file groups),
With this virtual file as a unit, the update date is updated when any file belonging to this virtual file is updated. Further, in FIG. 13, 11b
Corresponds to the final transfer date table 11a in the first embodiment, and similarly to the update date table 21b, one or more files used in the same business are defined as virtual files, and the client 10 uses this virtual file. Is issued as a unit to the server 20. Therefore, the final transfer date of the final transfer date table 11b is updated for each virtual file.

Incidentally, as the configuration diagram showing the file transfer system in this embodiment, the same FIG. 1 as in the first embodiment is used. 2 and 3 are used as a format used for message exchange between the server 20 and the client 10. Further, as the operations of the server 20 and the client 10, the flowcharts of FIGS. 6 and 7 used in the first embodiment are used.

The operation in this embodiment configured as described above is the same as that in the first embodiment except that the unit of transfer in the first embodiment is handled as a virtual file. Since it is the same as the operation, the description is omitted.

In this embodiment, since the transfer unit is the virtual file unit, it is possible to transfer a plurality of files with one transfer request, and the system throughput is improved. In addition, although this embodiment has been described based on the first embodiment, the configuration of the second embodiment may be applied, and the throughput is further improved.

Example 4. 14 to 16 are views for explaining still another embodiment of the present invention.
Is the server 20 that has received the transfer request from the client 10.
FIG. 15 and FIG.
6 is a flowchart for explaining the operation of the server 20 and the client 10, respectively.

The operation of this embodiment will be described below with reference to the drawings. Note that FIG. 1, which is the same as that of the first embodiment, is used as the configuration diagram showing the file transfer method in this embodiment. The message format used when the client 10 makes a transfer request to the server 20 uses the format shown in FIG. Furthermore, the file update date table 21a and the final transfer date table 11a also use FIGS. 4 and 5 used in the first embodiment, respectively.

When a file is required, the client 10 sends a file transfer request to the server 20 (step S1901). At this time, the client 10
Shows the name of the file that needs to be transferred and the last transfer date.
The message created in this format is transmitted to the server 20. The final transfer date is obtained from the date of the corresponding file name from the final transfer date table 11a. The server 20 receives this file transfer request (step S2001).
Then, the update date table 21a is searched to check whether or not the requested file exists in the own system (step S
2002). When the file does not exist in the system itself, the server 20 sets a hexadecimal number “80” to the first byte of the response message to the client 10 as shown in FIG. "No file" is sent to the client 10 as an answer to the file transfer (step S2004).

If the file exists in the system, the server searches the update date table 21a for the update date of the file (step S2003).
The update date obtained by the search is compared with the final transfer date included in the message at the time of the file transfer request, and it is determined whether the update date is newer than the final transfer date (step S2005), and the update date is newer. Figure 14
As shown in (b), the hexadecimal number "00" is set in the first byte of the response data to the client 10, and the contents of the file are set after the first byte and transmitted to the client 10 (step S200).
7).

When the update date is not later than the last transfer date, the hexadecimal "80" is set in the first 1 byte as shown in the format of FIG.
A response to the file transfer is transmitted to the client 10 with the portion of the processing result as "not required" (step S200)
6).

When hexadecimal "00" is set in the first byte as shown in FIG. 14B, step 2
When the file to be transmitted in 007 is too large to be transmitted at one time, the transmission of the corresponding file is continued (step S2008).

On the other hand, the client 10 receives the response to the file transfer request (step S1902) and checks the first byte of the received data (step S1).
903). If the first byte is "00" in hexadecimal, the rest of the data is judged to be the contents of the file and written to the file, and the file reception process is continued (step S
1904). After receiving the file, the final transfer date of the final transfer date table 11a is updated (step S190).
6).

If the first 1 byte is hexadecimal "80", the cause of the first 1 byte being "80" is judged from the processing result part following this first byte "80" (step S1905). The process ends. If there is a file to be further transferred, the above process is repeated.

As described above, in this embodiment, the server 1
When 0 responds to the client, the processing result and the file can be transmitted as one data, so the system throughput can be improved.

Example 5. FIG. 17 is a block diagram of a file transfer system showing still another embodiment of the present invention. FIG.
The configuration of No. 7 is different from the configuration of FIG. 1 shown in the first embodiment in that the client 10a is provided with the server information 13 having the time difference with each server 20 based on the client 10a and the address of the server 20. Yes, the points are different.

FIG. 18 is a diagram showing an example of the server information 13 described above. For example, the address of the server "SERVER001" is "0123456", which indicates that it is delayed by 5 hours from the client 10a. Further, FIG. 19 is a flow chart for explaining the operation of the client 10a in this embodiment. The operation of the server 20 is the same as the operation described in the first embodiment.

The operation of this embodiment having the above arrangement will be described below. The format of the message used between the server 20 and the client 10a in this embodiment is the same as that used in the first embodiment shown in FIGS.
To use. The update date table 21a and the final transfer date table 11a included in the server also use FIGS. 4 and 5 used in the first embodiment.

When a file is required, the client 10a sends a file transfer request to the server 20 (step S1005). Prior to transmission, information such as the address of the server to be connected and the time difference is obtained from the server information 13 (step S1001). The time difference value is checked from the obtained information (step S1002). If the time difference is not 0, the time difference is added to the final transfer date of the transfer request file to make it the final transfer date (step S100).
3). If the time difference is 0, the final transfer date of the transfer request file obtained from the final transfer date table 11a is used as it is (step S1004). Using the time thus obtained as the final transfer date, a message in the format shown in FIG. 2 is created and a transfer request is transmitted to the server 20 (step S1005). After that, the processing from the transmission of the file transfer request (steps S1006 to S1009) is the same as that of the first embodiment, and the description thereof is omitted.

As described above, in this embodiment, since the client 10a is made to have the time difference information with the server 20, it is possible to efficiently transfer files even between remote locations having a time difference.

In this embodiment, the client 10a executes the time difference addition process. However, the client 10a notifies the time difference with the server when the file transfer request is transmitted, and the server 20 adds the time difference when checking the update date. You may perform processing, such as. Further, the time difference stored in the server information 13 may be the time difference seen from the server 20 instead of the time difference seen from the client 10a.

Further, in this embodiment, the information regarding the time difference is provided as the server information 13 in the client 10a, but the server 2 is provided as the client information.
It may be set to 0. Further, this embodiment may be carried out in combination with any one of the above-mentioned first to fourth embodiments, and the throughput can be further improved.

Example 6. 20 to 22 are views for explaining still another embodiment of the present invention. FIG. 20 shows a message format when the client 10 makes a transfer request to the server 20, and FIGS. 21 and 22 respectively show this embodiment. 6 is a flowchart illustrating operations of the client 10 and the server 20 in the example. In the format shown in FIG. 20, the difference between the final transfer date and the date and time when the transfer request is made is set as "difference".
As the format used for the response from the server 20 to the client 10, FIG. 3 used in the first embodiment is used.

The operation of this embodiment, configured as described above, will be described below with reference to the drawings. Note that FIG. 1 used in the first embodiment is used as the configuration diagram of the file transfer method used in this embodiment. The update date table 21a and the final transfer date table 11a included in the server also use FIGS. 4 and 5 used in the first embodiment.

When the file is required, the client 10 sends a file transfer request to the server 20 (step S2203). At this time, the client 10
Obtains the current time (step S2201), and sends to the server 20 a message in which the difference between the current time obtained along with the name of the file that needs to be transferred and the last transfer date is created in the format of FIG. 20 (step S2202). . As the final transfer date, the date of the corresponding file name is obtained from the final transfer date table 11a.

When the server 20 receives this file transfer request (step S2301), the server 20 searches the update date table 21a to check whether the requested file exists in its own system (step S2302). If the requested file does not exist in the own system, the processing result portion of the format shown in FIG. 3 is transmitted to the client 10 as a response to the file transfer request with "no file" (step S2305).

If the file exists in the server 20, the server obtains the current time (step S2303).
In addition, the update date of this file is shown in the update date table 11a.
The search is performed to obtain the difference from the current time (step S2
304). The obtained difference is compared with the difference that the message at the time of the file transfer request has, and it is judged whether the difference indicated by the message of the file transfer request is larger (step S2306). If the difference is larger, the processing result is "transferred"
The reply to the file transfer request is transmitted to the client 10 (step S2308).

If the difference indicated by the file transfer request message is not larger, the processing result is "unnecessary" and is sent to the client 10 as a response to the file transfer request (step S2307). If the processing result is "transfer", the file is transmitted (step S2309).

On the other hand, the client 10 receives the response to the file transfer request (step S2204) and checks the portion of the processing result (step S2205). If the processing result is "transfer", the process proceeds to the file receiving process (step S2206). When the file has been received, the final transfer date of the final transfer date table 11a is updated (step S2207). The process is completed here. If there is a file to be transferred, the above operation is repeated.

As described above, according to this embodiment, it is possible to efficiently perform file transfer between points having a time difference without having the server information as a table as in the fifth embodiment.

Although this embodiment has been described based on the first embodiment, it may be carried out in combination with any one of the second to fifth embodiments, and the throughput can be further improved.

[0072]

As described above, according to the present invention, the file supplied device is provided with a table having the final transfer date of the file, and the file supplying device is provided with the table having the final transfer date of the file. At the time of request, the date based on the last transfer date is transmitted and compared with the date based on the update date of the file in the file supply device, so that only the file that needs to be transferred can be efficiently transferred.

Further, since only the necessary files are transferred by comparing the final transfer date and the update date, the transfer time and the transfer data amount can be reduced, so that the line cost can be reduced.

Further, since the table to be provided with the time difference from the file supply device is provided in the file supply device to transmit the data with the time difference corrected when the file transmission request is made, it is necessary without considering the time difference. It is possible to send only a file.

Since the file supply device is provided with a table having a time difference from the file supply device, and the time difference is corrected by the file supply device which has received the file transmission request, the time difference is also taken into consideration. It is possible to send only the necessary files without having to.

Further, the file-supplied device transmits the difference between the last transfer date and the current time of the device itself at the time of requesting the file transfer, and the file supply device obtains the difference between the update date and time and the current time of the device and transmits it. Since it is compared with the difference that has been made, it is possible to send only the necessary files without considering the time difference.

Further, since it is possible to request transfer of a plurality of files in the file transfer request message, it is possible to transfer a plurality of files with one file transfer request, and the efficiency of the system is improved.

Further, since one or more files used in a specific job or the like are grouped together, a plurality of files can be transferred by one file transfer request. Efficiency is improved.

Since the header for distinguishing whether the file transfer reply is the reply or the data is provided, the transmission of the file transfer reply can be omitted when transferring the file, and the transfer can be performed more efficiently.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a file transfer system according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a format at the time of a file transfer request according to the first embodiment of the present invention.

FIG. 3 is a diagram showing an example of a format at the time of replying to a file transfer request according to the first embodiment of the present invention.

FIG. 4 is a diagram showing an example of an update date table according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an example of a file final transfer date table according to the first embodiment of the present invention.

FIG. 6 is a flowchart illustrating the operation of the server according to the first embodiment of the present invention.

FIG. 7 is a flowchart illustrating the operation of the client according to the first embodiment of the present invention.

FIG. 8 is a diagram showing an example of a format when a file transfer request is made in the second embodiment of the present invention.

FIG. 9 is a diagram showing an example of a format at the time of replying to a file transfer request according to the second embodiment of the present invention.

FIG. 10 is a flowchart illustrating an operation of the client according to the second exemplary embodiment of the present invention.

FIG. 11 is a flowchart illustrating an operation of the server according to the second embodiment of the present invention.

FIG. 12 is a diagram showing an example of an update date table according to the third embodiment of the present invention.

FIG. 13 is a diagram showing an example of a final transfer date table according to the third embodiment of the present invention.

FIG. 14 is a diagram showing an example of a format at the time of replying to a file transfer request in Embodiment 4 of the present invention.

FIG. 15 is a flowchart illustrating an operation of the client according to the fourth exemplary embodiment of the present invention.

FIG. 16 is a flowchart illustrating an operation of the server according to the fourth embodiment of the present invention.

FIG. 17 is a diagram showing a configuration of a file transfer system according to a fifth embodiment of the present invention.

FIG. 18 is a diagram showing an example of server information according to the fifth embodiment of the present invention.

FIG. 19 is a flowchart illustrating an operation of the client according to the fifth embodiment of the present invention.

FIG. 20 is a diagram showing an example of a format when a file transfer request is made in the sixth embodiment of the present invention.

FIG. 21 is a flow chart illustrating operation of the client according to the sixth embodiment of the present invention.

FIG. 22 is a flow chart illustrating operation of the server according to the sixth embodiment of the present invention.

FIG. 23 is a diagram showing a configuration of a conventional file transfer system.

[Explanation of symbols]

10 clients, 11 final transfer date table, 12 files, 13 server information, 20 servers, 21 update date table, 22 files, 30 network.

Claims (8)

[Claims] 1. A system in which a file supply device that supplies a file and a file supply device that receives a file from the file supply device are combined, wherein the file supply device has the latest date of the file in the device itself. A first table having a last transfer date that is
A transmission request for transmitting a transfer request message in which a file name obtained by searching the first table when requesting the file transfer from the file supply device and first data based on the final transfer date are paired. Means, wherein the file supply device has a second table having a latest update date for updating a file in the own device; and the second table.
And processing the second data, which is the date based on the update date obtained by searching the table of FIG. 1, and the first data, and a reply message in which the requested file name and the processing result are paired. A file transfer method comprising: a response sending unit for sending, and a file is transferred only when the second data has a newer date. 2. The file transfer system according to claim 1, wherein the first data is a final transfer date, and the second data is an update date. 3. The file-supplied device has a third table in which the time difference between the self-device and the file supply device is registered, and the first data is obtained by searching from the third table. The file transfer method according to claim 1, wherein the file transfer method is a value obtained by calculating a time difference and the final transfer date, and the second data is an update date. 4. The file supply device has a fourth table in which a time difference between the device itself and the file supply device is registered, the first data is a final transfer date, and the second data is stored. The file transfer method according to claim 1, wherein is a date obtained by calculating the time difference obtained by searching the fourth table and the update date. 5. In a system in which a file supply device that supplies a file and a file supply device that receives a file from this file supply device are combined, the file supply device is A first table having a latest transfer date, which is the latest date transferred, the last transfer date obtained by searching the first table when requesting a file from the file supply device, and the current status of the device itself. First difference from time
And a transmission request means for transmitting a transfer request message in which the first difference and a file name are paired,
The file supply device includes a second table having a latest update date when the file in the device itself is updated;
Of the table, the difference between the update date and the current time of the device itself is obtained as a second difference, the first difference is compared and processed, and the requested file name and its processing result are obtained. And a response transmitting means for transmitting a response message including a pair, and the file is transmitted only when the first difference is larger. 6. The transmission requesting means creates a transfer request message including a plurality of pairs of a file name and its first data, and the reply transmitting means processes the transfer request message, The file transfer method according to any one of claims 1 to 5, wherein a reply message including a pair of a file name and a processing result thereof is transmitted. 7. The file transfer method according to claim 1, wherein the file is a virtual file configured as a group of one or more files. 8. The response transmitting means comprises means for adding a header to a response message and transmitting a file to be transferred subsequently to the header, according to any one of claims 1 to 5. File transfer method described.