JP2001005751A - Electronic mail system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the data amount of an electronic mail by transferring not an attached file itself but the address of the attached file. SOLUTION: A GW computer 5 divides an electronic mail transmitted from a 1st computer 1 into a message text and an attached file, the attached file is stored in the computer 5, and an HTML file being a list of attached files is further prepared and stored. The computer 5 reprepares an electronic mail obtained by adding the list of the attached files to the message text and transmits the electronic mail to a 2nd mail computer 4 via a 1st mail computer 3, and the electronic mail is stored in the computer 4. A computer 2 fetches electronic mails to the computer 2 itself from the computer 4 and also downloads an original attached file from the computer 5 by utilizing the list of the attached files when needed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic mail, and more particularly to a technique for reducing the load of electronic mail by transferring the URL of an attached file without transferring the attached file itself by electronic mail.

[0002]

2. Description of the Related Art FIG. 14 shows an example of a conventional electronic mail system. Sender's computer 10, sender's mail computer 30, receiver's computer 20, receiver's mail computer 4
0 are connected by the network 6. Sender's computer 1
The message 111 and the attached file 112 are transmitted by the outgoing mail control unit 11 by e-mail to the mail computer 3 on the transmitting side.
0, is transmitted to the mail computer 40 on the receiving side via the transmission server control unit 31 of the mail computer 30 on the transmitting side, and is stored in the mailbox 42 (arrow S5).
1). The emails stored in the mailbox 42 are
The received mail control unit 21 of the recipient computer 20 retrieves the message and restores it to the message 211 and the attached file 212 (arrow S52).

[0003]

However, in the above e-mail system, since the attached file is always transferred together, the line (Internet, LAN, telephone line, etc.) is proportional to the data amount of the attached file. There was a problem of applying a high load to the system. Further, since the attached file is temporarily stored in the mail server, there is a problem that the hard disk of the mail server is consumed in a large amount.

SUMMARY OF THE INVENTION In view of the above problems, the present invention reduces the data amount of an e-mail by transferring only the URL indicating the location of the attached file by an e-mail without transferring the substance of the attached file by an e-mail. And to reduce the amount of hard disk consumption of the mail server.

[0005]

FIG. 1 is a diagram showing the principle of the present invention for achieving the above object. The first computer 1, the second computer 2, the first mail computer 3, the second mail computer 4, and the first GW computer 5 are connected by a network 6, and electronic devices transmitted from the first computer 1 The mail is separated into a message text and an attached file by the first GW computer 5, the attached file is stored in the first GW computer 5, and the attached file list is displayed in HTML (HyperTe).
xt Markup Language) file is created and stored. The first GW computer 5 re-creates the e-mail with the attached message list added to the message text, sends the e-mail to the second e-mail computer 4 via the first e-mail computer 3, and sends the e-mail to the second e-mail computer 4. The e-mail is stored. The second computer 2 is a second mail computer 4
Retrieves an e-mail addressed to the user (arrow S1). Further, the second computer 2 displays and downloads the original attached file from the first GW computer 5 when necessary using the attached file list of the e-mail (arrow S).
2). In FIG. 1, the first computer 1 and the first GW
Although the computer 5 and the first mail computer 3 are different computers, the first computer 1 and the first GW computer 5 are the same computer, or the first GW computer 5 and the first mail computer 3 May be the same computer.

[0006]

FIG. 2 is a diagram showing a configuration example of an electronic mail system. The sender's computer 10 includes an outgoing mail control unit 11. Recipient's computer 20
Is composed of a received mail control unit 21 and a browser control unit 22. The mail computer 30 on the transmitting side includes a transmission server control unit 33. Email computer 40 on the receiving side
Comprises a receiving server control unit 41 and a mailbox 42. The GW computer 50 on the transmission side includes a mail disassembly control unit 51, a resource management control unit 52, and a mail retransmission control unit 5.
3, a download control unit 54, a WWW control unit 55, an exception list 56, and an application list 57. The sender's computer 10, the recipient's computer 20, the sender's mail computer 30, the receiver's mail computer 40, and the sender's GW computer 50 are connected by a network 6.

The e-mail transmitted by the sender's computer 10 is transmitted by the mail transmission control unit 11 to the GW computer 50 on the transmission side (arrow S10). If the e-mail address of the recipient is not registered in the exception list 56, the mail disassembly control unit 51 of the GW computer 50 on the transmission side analyzes the received e-mail, and if the attached file is specified, the e-mail Extracts the attached file part and performs resource management control unit 52
Call. If the recipient's e-mail address is registered in the exception list 56 or the attached file is not specified, the e-mail is sent to the e-mail computer 30.
(Arrow S11). Note that, depending on the received e-mail, the mail retransmission control unit 53 converts the protocol and transmits the converted e-mail (arrow S12).

[0008] The resource management control section 52 stores and manages the attached file extracted from the electronic mail. At the same time, it creates and manages an HTML file indicating the list and location of the attached files, and passes the URL of the HTML file to the mail retransmission control unit 53. The mail retransmission control unit 53 re-creates the electronic mail in which the attached file portion of the electronic mail received from the sender's computer 10 has been changed to the URL, and transmits the electronic mail to the mail computer 30 on the transmission side (arrow S12).

The sending server control unit 31 of the sending mail computer 30 sends the received e-mail to the receiving mail computer 40, and the receiving server control unit 41 of the receiving mail computer 40 sends the received e-mail. Is stored in the mailbox 42 (arrow S13).

The received mail control unit 2 of the recipient computer 20
1 is a mailbox 42 of the mail computer 40 on the receiving side.
Fetches an e-mail addressed to the user (arrow S14).

The recipient's computer 20 activates the browser control unit 22 by clicking the URL of the attached file received by e-mail (if the browser control unit 22 has already been activated, it uses the activated one). Do),
A list of attached files is displayed on the browser, and by selecting an attached file to be referred from the attached file list, the browser control unit 22 causes the WWW control unit 55, the download control unit 54, and the resource management control of the GW computer 50 on the transmission side to perform. The contents of the attached file are displayed on the browser via the unit 52. The attached file can also be taken into the recipient's computer 20 as a file using the function of the browser (arrow S15).

[0012] The mail transmission control unit 11 transmits the SMTP (Si
Mple Mail Transfer Protocol
ol) or HTTP (HyperText Tran)
sfer Protocol) and the G on the transmitting side.
It has a function of transmitting an e-mail to the W computer 50.

The mail disassembly control unit 51 includes an exception list 56
It has a function of analyzing the received e-mail by referring to the application list 57 and extracting the attached file from the e-mail. In addition, it has a function of calling the resource management control unit 52 and the mail retransmission control 53 according to the presence or absence of an attached file and the e-mail protocol. Email decomposition control unit 51
Uses file transfer and file sharing to transfer the attached file to the resource management control unit 52.

The mail retransmission control unit 53 recreates an electronic mail in which the attached file portion of the electronic mail received from the sender's computer 10 has been changed to a URL. Also, in a broadcast mail with multiple specified email addresses,
Recreate the email for each email address. Also, HTT
The electronic mail received by P has a function of changing it to SMTP and transmitting it to the mail computer 30 on the transmission side.

The transmission server control unit 31 sends the e-mail to S
It has a function of transmitting to the mail computer 40 on the receiving side using MTP. The receiving server control unit 41 has a function of storing the received e-mail in the mailbox 42.

The received mail control unit 21 sends a POP (Pos)
t Office Protocol), and has a function of receiving an electronic mail addressed to the user from the mailbox 42 of the mail computer 40 on the receiving side.

The resource management unit 52 stores and manages the attached file extracted from the electronic mail. At the same time, a list of attached files and an HTML file indicating the location are created and managed, and the attached files are periodically checked, and those whose storage days have elapsed are deleted, and the transmission-side GW computer 5 is checked.
It also has a function of effectively using the 0 disk.

The download control unit 54 has a function of authenticating the validity of the downloader and instructing the resource management control 52 to access the attached file. In addition,
The download control unit 54 includes a GW computer 50 on the transmission side,
Alternatively, it may operate on the recipient's computer 20. For example,
By using Java or the like, the download control unit 54 of the GW computer 50 on the transmission side can be downloaded to the computer 20 of the receiver and operated.

The WWW control unit 55 controls the WWW server side, and the browser control unit 22 controls the WWW client side. The WWW control unit 55 and the browser control unit 22 exchange data using WWW HTTP.

In the exception list 56, the user defines the e-mail address of the recipient who receives in the conventional e-mail format regardless of the data amount of the attached file.

In the application list 57, an electronic mail having a data amount less than the data amount defined here is transmitted in a conventional electronic mail format. The data amount is defined by the user for each recipient's domain name.

In FIG. 2, the sender's computer 10,
The GW computer 50 on the transmitting side and the mail computer 30 on the transmitting side are different computers, but the computer 10 of the sender and the GW computer 50 on the transmitting side are the same computer, or the G on the transmitting side.
The W computer 50 and the mail computer 30 on the transmission side may be the same computer. Further, the mail disassembly control unit 51, the resource management 52, the mail retransmission control unit 53, the download control unit 54, and the WWW control unit 55 may operate on separate computers and communicate with each other through the network 6. Further, the exception list 56 and the application list 57 may be the same list.

FIG. 3 is a diagram showing an example of information managed by the resource management control unit. Home path 531, caller identifier 532, 533, caller identification 534, attached file 53
5, 536 and recipient identifiers 537, 538. The home path 531 is determined by the definition of the user.

The sender identifiers 532 and 533 are for managing mail senders, and are managed using, for example, the sender's mail address. Caller identifier 532, 5
33 is deleted when all the files under it disappear. For example, in the case of the sender identifier 533, the sender identifier 5
34, attached files 535, 536, recipient identifier 53
When all 7, 538 are deleted, the caller identifier 53
3 is also deleted.

The outgoing identifier 534 manages outgoing mail, and uses, for example, the outgoing date and time of the mail.
As a result, the data whose storage days have passed can be deleted. The number of storage days is determined by the definition of the user. The transmission identifier 534 is deleted when there are no more files under it. For example, in the case of the transmission identifier 534,
Attachments 535, 536, recipient identifiers 537, 5
When all 38 have been deleted, the outgoing identifier 534 is also deleted.

The attached files 535 and 536 are created with the name of the attached file of the mail. Attached file 535,
536 is deleted when all of the receiver identifiers 537 and 538 disappear or the storage days have elapsed.

The recipient identifiers 537 and 538 are used to manage the recipients of the mail, and use, for example, the recipient's mail address. However, in the broadcast mail, the recipient's email address is visible to a third party, and the recipient's email address is encrypted and used so that the attached file cannot be downloaded by impersonating the third party.
The receiver identifiers 537 and 538 are deleted when the deletion instruction from the mail receiver or the number of storage days has elapsed. When the download is controlled only by HTML, the receiver identifier 53
7,538 files with attached files 535,536
Is recorded.

FIG. 4 is a diagram showing an example of an exception list and an application list. The exception list 56 is composed of a group of e-mail addresses of recipients, and e-mails to e-mail addresses registered here are transmitted in a conventional e-mail format regardless of the amount of data. This allows a recipient in an environment where a browser is not used to receive the e-mail.

The application list 57 is composed of the recipient's domain name and the limit data amount. When the e-mail to the receiver belonging to the domain name exceeds the limit data amount, the attached file is separated and the e-mail is sent. Send. On the other hand, when the wing does not exceed the limit data amount, the wing is transmitted in a conventional e-mail format. For example, xxx. or. If the e-mail to the recipient belonging to the jp domain exceeds 300 Kbytes, the e-mail is transmitted with the attached file separated. Similarly, xxx. co. If the e-mail to the recipient belonging to the jp domain exceeds 1000 Kbytes, the e-mail is transmitted with the attached file separated. Further, if the email to recipients not belonging to any of the above domains exceeds 500 Kbytes,
The e-mail is sent with the attached file separated.

FIG. 5 is a diagram showing an example of an attached file list. By clicking on the URL received by e-mail, it is displayed on the browser 60. Browser 60
It comprises an address display area 61 and an attached file list display area 62. In the address display area 61, the URL of the receiver identifier or the URL (http
p: // a / b / c / d / e. htm: 8080) is displayed. In the attached file list display area 62, read buttons 62a and 62d for reading attached files, delete buttons 62b and 62e, and attached file names 62c and 62f are displayed.
Is displayed.

A of the URL in the address display area 61 corresponds to the IP address of the GW computer 50 on the transmitting side, b corresponds to the home path 531, c corresponds to the caller identifier 533, and d corresponds to the caller identifier 534. Corresponding to e. htm is
An HTML file for operating the receiver identifiers 537, 538 or the download control unit 54. 80
Reference numeral 80 denotes a port number for the WWW control unit 55 of the transmitting GW computer 50 to operate as a WWW server.
This port number is determined by the definition of the user.

FIG. 6 is a diagram showing an example of an electronic mail system using a firewall. Assuming that the sender's mail computer 30 also functions as a firewall and a mail server, the sender's mail computer 30 transfers the attached file 112 of the received e-mail to the WWW server computer 70 via the router 80 by file transfer. Each is stored in the attached file 113 (arrow S21). The mail computer 30 on the transmission side adds the URL of the attached file 113 stored in the WWW server computer 70 to the received e-mail message 111 and transmits it to the Internet 61 (arrow S22). The attached file 113 stored in the WWW server computer 70 is transmitted from the Internet 61 to the WWW.
Is downloaded via the router 80 (arrow S23).

FIG. 7 is a flowchart showing the processing of the electronic mail system when using electronic mail software. Upon receiving the mail sender notification from the sender computer 10, the transmitting GW computer 50 transmits the mail sender notification to the transmitting mail computer 30 as it is (arrow S3).
1). When receiving the response of the mail sender notification (OK in the figure) from the mail computer 30 on the transmission side, the GW computer 50 on the transmission side transmits the response of the mail sender notification to the sender computer 10 as it is. Upon receiving the mail recipient notification from the sender's computer 10, the GW computer 50 on the transmitting side records the recipient included in the mail recipient notification and sends a response (OK in the figure) of the mail recipient notification to the sender. The data is transmitted to the computer 10 (arrow S32).

Upon receiving the mail data notification from the sender's computer 10, the GW computer 50 on the transmitting side decomposes the mail data and creates a mail in which the attached file portion is rewritten into a URL. Next, a mail recipient notification is transmitted to the mail computer 30 on the transmission side (arrow S33). Response to mail recipient notification from mail computer 30 on the sending side (OK in the figure)
Is received, the transmitting GW computer 50 transmits a mail data notification (the previously created mail) to the transmitting computer 10 (arrow S34). When a response (OK in the figure) of the mail data notification is received from the mail computer 30 on the transmitting side,
The GW computer 50 on the transmission side transmits the response of the mail data notification to the computer 10 of the sender as it is. Here, the GW computer 50 on the transmission side repeats the processing of the mail data notification from the mail recipient notification by the number of recipients notified by the mail recipient notification from the sender's computer 10. Then, a response of the mail data notification is returned to the sender's computer 10.

FIG. 8 is a flowchart showing processing of the electronic mail system when using a browser. When the text and the attached file to be transmitted from the mail are uploaded from the sender's computer 10, the GW computer 50 on the transmitting side is uploaded.
Records the mail sender and the mail recipient, creates a mail sender notification, and sends it to the mail computer 30 on the transmitting side (arrow S41). When receiving the response (OK in the figure) of the mail sender notification from the mail computer 30 on the transmitting side, the GW computer 50 on the transmitting side creates a mail recipient notification and transmits it to the mail computer 30 on the transmitting side (arrow S42). ).

When a response (OK in the figure) of the mail recipient notification is received from the mail computer 30 on the transmitting side, the G on the transmitting side is received.
The W computer 50 creates a mail in which the attached file portion is rewritten to the URL, and sends a mail data notification (the previously created mail) to the sending computer 10 (arrow S43).
When a response (OK in the figure) of the mail data notification is received from the mail computer 30 on the transmission side, the GW computer 50 on the transmission side receives the response.
Sends a completion notification to the sender's computer 10. here,
The GW computer 50 on the transmission side repeats the process from the mail recipient notification to the mail data notification by the number of recipients, and returns a completion notification to the sender's computer 10 when all the processes are completed.

FIG. 9 is a flowchart showing the processing of the sender in the electronic mail system when using electronic mail software. In the description of this flowchart, the number following S indicates a step number. [S901] Wait for an instruction from the sender's computer or user, and upon receiving the instruction, proceed to step S902. [S902] If it is a termination instruction from the user, the processing is terminated. Otherwise, the process proceeds to step S903. [S903] If it is a recipient notification (e-mail protocol data) from the sender's computer, the flow advances to step S907. Otherwise, the process proceeds to step S904. [S904] If it is a mail data notification (e-mail protocol data) from the sender's computer, step S908.
Proceed to. Otherwise, the process proceeds to step S905.

[S905] The transmitting GW computer transmits the data (e-mail protocol data) received from the transmitting computer as it is to the transmitting mail computer.
Wait for a response from the sending mail computer. [S906] The data (protocol data of the e-mail) received from the mail computer on the transmitting side is transmitted as it is to the computer of the sender, and the process proceeds to step S901. [S907] Record the recipient name included in the recipient notification (e-mail protocol data) received from the sender's computer, and send the recipient OK (e-mail protocol data) to the sender's computer. The process proceeds to S901. [S908] If the e-mail address of the recipient is registered in the exception list, the process proceeds to step S912. Otherwise, the process proceeds to step S909.

[S909] If the mail data notification (e-mail protocol data) received from the sender's computer includes an attached file, the flow advances to step S910. Otherwise, the process proceeds to step S912. [S910] If the e-mail address of the recipient is registered in the domain name of the application list and the data amount of the attached file exceeds the limited data amount, step S911.
Proceed to. Otherwise, the process proceeds to step S912. [S911] Save the attached file in the mail data,
Re-create the email with the URL of the attached file. [S912] When the process is completed for all the stored recipient names, the process proceeds to step S917. Otherwise, the process proceeds to step S713.

[S913] A recipient notification (e-mail protocol data) is transmitted to the transmitting mail computer based on the stored recipient name, and a response from the transmitting mail computer is waited for. [S914] If it is an OK notification (email protocol data) from the mail computer on the transmission side, the process proceeds to step S915. Otherwise, the process proceeds to step S918. [S915] A mail data notification (e-mail protocol data) is sent to the sending mail computer, and a response from the sending mail computer is waited for. [S916] If it is an OK notification (e-mail protocol data) from the mail computer on the transmission side, the process proceeds to step S912. Otherwise, the process proceeds to step S918.

[S917] Data O is sent to the sender's computer.
K (e-mail protocol data) is transmitted, and the process proceeds to step S901. [S918] Data (e-mail protocol data) received from the sender's mail computer to the sender's computer
Is transmitted as it is, and the process proceeds to step S901.

FIG. 10 is a flowchart showing the process of the sender in the electronic mail system when using a browser. In the description of this flowchart, the number following S indicates a step number. [S1001] Wait for an instruction from the sender's computer or user, and upon receiving the instruction, step S1002
Proceed to. [S1002] If the user gives a termination instruction, the processing is terminated. Otherwise, the process proceeds to step S1003. [S1003] If the mail data is uploaded from the sender's computer, the process proceeds to step S1005. Otherwise, the process proceeds to step S1004. [S1004] WWW protocol data is exchanged between the sender's computer and the GW computer on the transmitting side, and the flow advances to step S1001.

[S1005] The GW computer on the transmission side transmits a sender notification (e-mail protocol data) to the computer of the sender, and waits for a response from the mail computer on the transmission side. [S1006] If it is an OK notification (e-mail protocol data) from the mail computer on the transmission side, step S100
Proceed to 7. Otherwise, the process proceeds to step S1018. [S1007] The name of the recipient included in the data uploaded from the sender's computer is recorded, and step S1008 is performed.
Proceed to. [S1008] If the e-mail address of the recipient is registered in the exception list, the process proceeds to step S1012. Otherwise, the process proceeds to step S1009.

[S1009] If the attached file is included in the data uploaded from the sender's computer, the flow advances to step S1010. Otherwise, step S101
Proceed to 2. [S1010] If the e-mail address of the recipient is registered in the domain name of the application list and the data amount of the attached file exceeds the limited data amount, step S10
Proceed to 11. Otherwise, the process proceeds to step S1012. [S1011] The attached file uploaded from the sender's computer is saved, and a mail is created with the attached file URL. [S1012] When the process is completed for all the stored recipient names, the process proceeds to step S1017. Otherwise, the process proceeds to step S1013.

[S1013] To the mail computer on the transmission side,
A notification of the recipient (e-mail protocol data) is transmitted based on the stored recipient name, and a response from the mail computer on the transmitting side is waited for. [S1014] If it is OK notification (e-mail protocol data) from the mail computer on the transmission side, step S101
Go to 5. Otherwise, the process proceeds to step S1018. [S1015] A mail data notification (e-mail protocol data) is sent to the sending mail computer, and a response from the sending mail computer is waited for. [S1016] If it is an OK notification (e-mail protocol data) from the mail computer on the transmission side, step S101.
Proceed to 2. Otherwise, the process proceeds to step S1018.

[S1017] The mail transmission success is transmitted to the sender's computer, and the flow advances to step S1001. [S1018] A mail transmission failure is transmitted to the sender's computer, and the flow advances to step S1001.

FIG. 11 is a flowchart showing the processing of the recipient in the electronic mail system. In the description of this flowchart, the number following S indicates a step number. [S1101] Wait for an instruction from the user, and upon receiving the instruction, proceed to step S1102. [S1102] If it is a termination instruction, the processing is terminated. Otherwise, the process proceeds to step S1103. [S1103] All mails of the recipient are extracted from the mailbox of the mail computer on the receiving side to the computer of the recipient.
[S1104] If there is no mail to be extracted, the process proceeds to step S1101. Otherwise, the process proceeds to step S1105.

[S1105] The retrieved mail is displayed. [S1106] When the URL of the extracted mail is selected, the process proceeds to step S1107. Otherwise, step S
Proceed to 1101. [S1107] If the browser has been started, step S
Proceed to 1109. Otherwise, the process proceeds to step S1108. [S1108] The browser is started. [S1109] Display the attached file list on the browser,
An operation (read, delete) is performed from the attached file list, and after the operation is completed, the process proceeds to step S1101.

FIG. 12 is a flowchart showing the WWW processing in the electronic mail system. In the description of this flowchart, the number following S indicates a step number. [S1201] Wait for an instruction from the browser, and upon receiving the instruction, go to step S1202. [S1202] If it is a termination instruction, the processing is terminated. Otherwise, the process proceeds to step S1203. [S1203] If the received instruction is a deletion, step S1
Proceed to 204. Otherwise, the process proceeds to step S1208. [S1204] If the deletion instruction is valid (the specified file exists), the flow advances to step S1205. Otherwise, the process proceeds to step S1211.

[S1205] The specified attached file is deleted from the GW computer on the transmitting side. When all the attachments of the recipient are deleted, the recipient identifier is also deleted. [S1206] If it is the last recipient (there is no other recipient identifier), the process proceeds to step S1207. Otherwise, the process proceeds to step S1201. [S1207] From the GW computer on the transmission side, the attached file and the transmission identifier set as the processing target are deleted, and step S12 is performed.
Go to 01. [S1208] If the received instruction is read, step S1 is executed.
Go to 209. Otherwise, the process proceeds to step S1211.

[S1209] If the read instruction is valid (the specified file exists), the flow advances to step S1210. Otherwise, the process proceeds to step S1211. [S1210] The contents of the specified attached file are transmitted to the browser, and the flow advances to step S1201. [S1211] An error message is sent to the browser,
Proceed to step S1201.

FIG. 13 is a block diagram of the electronic mail system. The computer includes a control unit 1301 including a CPU.
, Memory unit 1302, display unit 1303, input unit 1304, CD-ROM drive unit 1
305 and a disk unit 1306. These units are connected via a system bus A. The control unit 1301 executes a program storing the processing of the e-mail system. The memory unit 1302 includes a memory such as a RAM and a ROM, and stores programs to be executed by the control unit 1301, necessary data obtained in the course of processing, and the like. Display unit 1
Reference numeral 303 denotes a CRT, an LCD (liquid crystal display panel), or the like, and displays various screens. The input unit 1304 is
It consists of a keyboard, a mouse, etc.

The CD-ROM 1307 stores a program for executing processing of the electronic mail system.
The program is installed in the disk unit 1306 from the CR-ROM 1307 set in the CD-ROM drive unit 1305. Then, when the computer is started, the program read from the disk unit 1306 is stored in the memory unit 1302. In this state, the control unit 1301 (CPU)
According to the program stored in the memory unit 1302, processing related to the e-mail system is executed. Although a program describing processing relating to the e-mail system is provided on the CD-ROM 1307, the storage medium of the program is not limited to this.
It is also possible to use a storage medium such as a magnetic disk such as a floppy disk or a magnetic tape depending on the computer constituting the system.

[0054]

As described above, according to the present invention, in an electronic mail for transferring an attached file, only the URL of the attached file is transferred without transferring the substance of the attached file, thereby reducing the data amount of the transferred mail. The load on the line can be reduced, and the usage of the mail server and the hard disk of the mail recipient can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of an electronic mail system according to the present invention.

FIG. 2 is a diagram illustrating a configuration example of an electronic mail system.

FIG. 3 is a diagram illustrating an example of information managed by a resource management control unit.

FIG. 4 is a diagram illustrating an example of an exception list and an application list.

FIG. 5 is a diagram illustrating an example of an attached file list.

FIG. 6 is a diagram showing an example of an electronic mail system using a firewall.

FIG. 7 is a flowchart showing processing of the electronic mail system when using electronic mail software.

FIG. 8 is a flowchart showing processing of the electronic mail system when using a browser.

FIG. 9 is a flowchart showing processing of a sender in an electronic mail system when using electronic mail software.

FIG. 10 is a flowchart showing processing of a sender in an electronic mail system when using a browser.

FIG. 11 is a flowchart showing a process of a recipient in the electronic mail system.

FIG. 12 is a flowchart showing WWW processing in the electronic mail system.

FIG. 13 is a configuration diagram of an electronic mail system.

FIG. 14 is a diagram showing an example of a conventional electronic mail system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st computer 2 2nd computer 3 1st mail computer 4 2nd mail computer 5 1st GW computer 6 Network 10 Sender's computer 11 Outgoing mail control part 20 Recipient's computer 21 Received mail control part 22 Browser control unit 30 Sending mail computer 31 Sending server control unit 40 Receiving mail computer 41 Receiving server control unit 42 Mailbox 50 Sending GW computer 51 Mail division control unit 52 Resource management control unit 53 Mail retransmission control Unit 54 download control unit 55 WWW control unit 56 exception list 57 application list 61 Internet 70 WWW server computer 80 router

Claims (6)

[Claims] 1. An electronic mail system capable of transmitting an attached file, a mail disassembly control unit for extracting an attached file portion from the electronic mail, a resource management control unit for recording and managing the extracted attached file, URL (Uniform Resource Lo)
An e-mail system comprising: a mail retransmission control unit for re-creating an e-mail by using a WWW (World Wide Web); and a WWW control unit for downloading an attached file using the WWW (World Wide Web). . 2. Only at the URL notified by the received mail,
2. The electronic device according to claim 1, further comprising a resource management control unit and a download control unit that guard the third party from abusing the attached file by enabling the operation of the attached file. Mail system. 3. In a broadcast mail, a mail is re-created for each mail address, and the mail is transmitted to each mail address, so that the mail address is leaked to a third party and misused. 2. The electronic mail system according to claim 1, further comprising a mail disassembly control unit and a mail retransmission control unit for guarding. 4. The electronic device according to claim 1, further comprising a resource management control unit that can delete the attached file extracted from the electronic mail from a recipient of the electronic mail and automatically deletes the file after a lapse of a storage period. Mail system. 5. An application list for registering a data amount of an electronic mail, and controlling a conventional electronic mail without separating an attached file when the data amount is smaller than the registered data amount,
2. The e-mail system according to claim 1, further comprising an exception list for controlling the conventional e-mail without separating the attached file by registering the e-mail address of the recipient. 6. A method of extracting an attached file part of an e-mail, storing the extracted part in a file, and replacing the attached file part of the e-mail with the URL of the stored file, thereby reducing the data size of the e-mail, A machine-readable storage medium storing a function of displaying and downloading stored files on a WWW browser.