JP2001156831A - Electronic mail system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electronic mail system which stores broadcast electronic mails of the same contents in a storage device without wasting the storage capacity of the storage device of a mail server. SOLUTION: A common data file area 17, where the text of an electronic mail transmitted through a network is stored in a file having an identifier which identifies the text of the electronic mail and is read out from the electronic mail, and an individual data file area 18 where the identifier is stored in multiple receiver files corresponding to terminals 1, 2, and 3 of multiple receivers which are to receive the next of the electronic mail are provided. An electronic mail read means 19 retrieve the identifier from the individual data file area and reads out the electronic mail text in the file having this retrieved identifier from files in the common data file area 17 to transmit it to terminals of multiple receivers, and thus the storage capacity of the storage device is prevented from being wasted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an e-mail system for efficiently operating a mail server for sending, receiving, storing and managing e-mails of the same content transmitted in a network environment, that is, e-mails to be broadcast. It is.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a configuration diagram of a conventional electronic mail system described in Japanese Patent Publication No. 50; In FIG. 18, 101 is a mail server, 10
2 is a communication network, 103 to 105 are user terminal devices, 10
Reference numerals 6 to 108 denote storage areas for mail destinations, transmission side information, and mail attributes provided corresponding to the terminal devices 103 to 105, respectively, and reference numeral 109 denotes a mail body storage area.

[0003] In this electronic mail system, for example, when a user of the terminal device 103 transmits a mail having the same contents to the users of the terminal devices 104 and 105 using a broadcast service, the terminal device 103 transmits the mail to the user. A mail and a command including mail attributes indicating transmission side information, progress mail, express mail, and the like are input, and in response to the command, the mail server 101 stores the body of the input mail in the mail body storage area 109, Next, the destination of the mail, the sender information, and the attribute of the mail are stored in the storage area 10 corresponding to each of the terminal devices 104 and 105 as the destinations.
7 and 108.

Further, mail server 101 stores the correspondence between the information previously stored in storage areas 107 and 108 and the respective mail texts. When the user of the terminal device 104 inputs a predetermined read command, the storage area 1
The destination of the mail, the sender information, the attribute of the mail, and the body part of the mail stored in the storage area 109 corresponding to the information are transmitted to the terminal device 104. Similarly, when the user of the terminal device 105 inputs a predetermined read command, the destination of the mail stored in the storage area 108, the information on the sender side, the attribute of the mail, and the mail stored in the storage area 9 corresponding to the information. The text of the sent mail is transmitted to the terminal device 5.

[0005]

As described above, in the conventional electronic mail system, for example, a part of the broadcast destination address of the broadcast mail indicates a receiver on another computer on the network, and the receiver address For example, the broadcast mail was transferred to the mail server, or the user who received the broadcast mail on another host resent the mail to the user on the mail server. If the broadcast mail is not received at once by the mail server, the mail containing the same body received with a time delay will be judged to be a different mail. Since there is no means for assuming the same, there is a problem in that a plurality of body parts are stored and the storage capacity of the storage device of the mail server is wasted. In addition, there is a problem that the same processing is repeated a plurality of times, so that processing time is wasted.

[0006] In addition, even after all of a plurality of recipients of the same broadcast mail have read the mail, the body part of the broadcast mail is not deleted while being stored on the mail server. There is a problem that the used capacity of the apparatus increases monotonously. Furthermore, since the text storage area is single, if the partition of the storage device in which the text storage area is arranged becomes full, it is impossible to receive mail any more.

[0007] The present invention has been made to solve the above-described problems, and is intended for use even when a recipient address shown in a broadcast destination list of a broadcast mail comes via another computer. Also, even when the broadcast mail is transferred from another mail server, the same broadcast mail does not waste the storage capacity of the storage device of the mail server, and all the recipients of the broadcast mail read the mail. Then, the text is deleted, and the object is to obtain an e-mail system that does not hinder the storage of the text on the mail server even if the size of the text part becomes enormous.

[0008]

According to a first aspect of the present invention, there is provided a first storage means in which an electronic mail text is stored in a plurality of files having an identifier for identifying an electronic mail text, and a plurality of files for receiving the electronic mail text. A second storage unit in which the identifier is stored in a plurality of recipient files corresponding to each of the recipients, and an identifier for identifying the body of the electronic mail from the electronic mail transmitted via the network, Analyzing means for analyzing whether or not the file having the identifier exists in the first storage means; and transmitting when the analysis means has determined that the file having the identifier exists in the first storage means. Storing the identifier in a recipient file of the second storage means corresponding to a recipient receiving the text of the electronic mail, and storing the identifier in the first storage means When it is analyzed that the file having the identifier does not exist therein, a file having the identifier is newly created in the first storage unit, and the text of the transmitted e-mail is stored in the file, Storage processing means for storing the identifier in a plurality of recipient files in the second storage means corresponding to a recipient receiving the transmitted e-mail text;
Of the plurality of recipient files stored in the storage means, an identifier for identifying the body of the e-mail to be transmitted is searched, and the body of the e-mail in the file having the searched identifier is stored in the first storage. Reading means for reading from the file of the means, and transmitting the read e-mail text to the terminals of the plurality of recipients via a network.

The second invention is characterized in that when the analysis means analyzes that the file having the identifier exists in the first storage means, the electronic mail text stored in the file in the first storage means is read. Storage processing means for storing in the second storage means a difference in the transmitted route from the text of the transmitted e-mail, and the transmitted processing stored in the recipient file of the second storage means Reading means for transmitting the difference in the route to the terminals of the plurality of recipients via a network together with the electronic mail text read from the file in the first storage means.

[0010] A third invention is a storage processing means for generating a list of a plurality of recipients for receiving the electronic mail text in a file of the first storage means, and a receiver which has received the electronic mail text, It is determined whether or not the recipient has been designated to be deleted from the list of recipients. If the designation has been made to delete the recipient, the recipient file in the second storage means corresponding to the recipient who received the e-mail text is stored in the recipient file. Reading means for deleting the identifier of the e-mail from the list of recipients, and deleting the file in which the list is generated when all of the list of the recipients are gone. It is provided with.

[0011] In a fourth aspect of the present invention, it is determined whether or not the storage period of the electronic mail body set by the receiver has expired, and when the storage period has elapsed, the electronic mail body of the second storage means is received. In addition to deleting the identifier in the recipient file corresponding to the recipient, deleting the recipient who received the e-mail from the list of recipients, and generating the list when the list of recipients is completely lost. And a reading means for deleting the file.

According to a fifth aspect of the present invention, there is provided a data type determining means for determining a data type of an electronic mail text, a data compressing means for compressing data of the electronic mail text in accordance with the data type, and a compressed electronic data. Data decompression means for decompressing the data of the mail text, wherein the storage processing means determines a compression method of the data of the text of the email based on the data type of the text of the email determined by the data type determination means. Then, a file having a file extension indicating the compression method and an identifier for identifying the body of the e-mail is created in the first storage means, and the e-mail body compressed by the data compression means is included in the created file. The reading means reads out the compressed e-mail text stored in the file of the first storage means, and reads the data. The e-mail text is compressed based on the file extension of the file of the first storage means in which is decompressed by the data decompression means.

According to a sixth aspect of the present invention, a compressed electronic mail text stored in a file of the first storage means is read out, and the compressed electronic mail text and an extension determined by the storage processing means are read. It is provided with reading means for transmitting to the terminals of the plurality of recipients via a network.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a configuration diagram of an electronic mail system showing a typical case to which the present invention is applied. In FIG. 1, reference numerals 1, 2, and 3 denote terminals of the e-mail user-a, user-b, and user-c, respectively. melco. c
o. mail servers A and 5 that manage jp domains are ho
n. melco. co. The mail servers B and 6 that manage the jp domain are terminals of the user user-d of the mail server B.

In today's distributed system environment, a plurality of mail servers have mail addresses, and mail is automatically transferred from each mail server to a user's desired mail server at the convenience of the user.

For example, in the environment of FIG.
ra isl. melco. co. jp domain users user-b and hon. melco. co. j
When broadcasting an e-mail to the user-c of the p-domain, the user-a sends the user-a to the destination of the e-mail.
b @ isl. melco. co. jp and user-
c @ hon. melco. co. jp is specified, and a mail is transmitted from the user-a.

At this time, the mail server A4 has the user-
b @ isl. melco. co. jp is considered to be received by the host, and the user-b of the host
User-c @ ho
n. melco. co. jp mail is hon. m
elco. co. Transfer to the mail server B5 that manages the jp domain. Here, the mail server B5 receives the mail once, but the user us on the mail server B5.
er-c is the user-c @
isl. melco. co. jp, the mail server B5 sends this mail to isl. melc
o. co. mail server A which manages jp domain
Transfer to 4.

At this point, the mail server A4 receives the received u
The mail addressed to ser-c is stored in the user-c mailbox of the host. In such a situation,
In the conventional technology, even if the same mail is transmitted by user-a, the mail to user-b and user-c is not received at once, but is determined to be another mail, and is stored twice in the body storage area. The Rukoto.

Similarly, the user user-a sends the destination user
r-b @ isl. melco. co. jp and user-
d @ hon. melco. co. After broadcasting the mail to jp, the user user-d who received the mail sends the mail to user-c @ isl. melco. co. jp
In this case, the mails received by user-b and user-c are regarded as different mails on the mail server A4 even though the contents of the mails received by the user-b and user-c are the same. Will be.

FIG. 2 is a configuration diagram of the mail server according to the first embodiment. In FIG. 2, reference numeral 11 denotes a mail server;
Is a communication network, 13 is an e-mail receiving means, 14 is an e-mail transmitting means, 15 is a Message-ID analyzing means, 1
6 is a data storage processing means, 17 is a common data file area, 18 is an individual data file area, and 19 is an e-mail reading means. FIG. 3 is a flowchart showing the operation of the mail server 11 shown in FIG. The operation of the first embodiment will be described with reference to FIGS.

When the mail server 11 starts the processing (step S1), the mail server 11 determines whether the processing request received from the communication network 12 is an electronic mail receiving processing or a reading processing of a stored mail by a user. (Step S
2). Here, in the case of an e-mail reception process, the e-mail receiving means 13 receives the e-mail and determines whether the e-mail is addressed to the own domain (step S3). In the case of an electronic mail addressed to the own domain, the electronic mail is passed to the Message-ID analyzing means 15.

The Message-ID analyzing means 15 reads the value of the Message-ID field for uniquely identifying each individual e-mail from the header of the received e-mail, and stores a file having this value as a name in the common data file area. 17 is analyzed (step S4). Thereafter, the data of the e-mail is passed to the data storage processing means 16 together with the analysis result. The data storage processing means 16 performs a new process if the file does not exist (step S5), and performs an additional process if the file exists (step S6).

On the other hand, if it is determined in step S3 that the received mail is not an e-mail addressed to the own domain, this e-mail is transferred to the e-mail transmitting means 14, and is searched for a mail server in the transfer destination domain and transferred. (Step S7). If the result of step S2 is a process of reading an e-mail by the user, the e-mail reading means 19 performs a reading process (step S8).

FIG. 4 is a flowchart showing the operation of the new processing performed by the data storage processing means 16. When the new process is started (step S11), a file having a name of the previously analyzed Message-ID field in the common data file area 17 is newly generated (step S12), and the e-mail is stored in the new file. Of the individual data file area 1 (step S13).
8 in the file corresponding to each recipient in the message.
-Store (additionally) the ID (step S14) and end the process (step S15).

FIG. 5 is a flowchart showing the operation of the additional processing performed by the data storage processing means 16. When the adding process is started (step S21), the message of the new recipient in the individual data file area 18 is added to the message.
The ID is (added) stored (step S22), and the process is terminated (step S23).

FIG. 6 is a flowchart showing the operation of the reading process performed by the electronic mail reading means 19. When the reading process is started (step S31), the message from the user's file in the individual data file area 18 is deleted.
The e-ID is checked (step S32), an e-mail is read from the file having the name of the found Message-ID field in the common data file area 17 (step S33), and the read e-mail text is read. It is sent to the user (step S34), and the process is terminated (step S35).

As described above, according to the present embodiment, a broadcast type e-mail is stored as one data on the mail server 11 without storing a copy for each user at each destination. The storage capacity of the storage device in the mail server 11 can be prevented from being wasted, and the name of a file created in the common data file area 17 can be changed to a Message-ID field that can generally uniquely identify each electronic mail. , The same effect can be obtained for a broadcast mail received with a delay via another mail server.

Further, by separating the common data file area 17 and the individual data file area 18, the size of the user individual file area increases and decreases as the number of users increases and the number and size of the e-mail data itself are stored. It becomes possible to independently and flexibly manage the storage capacity of the device.

It should be noted that the uniqueness of the Message-ID is based on the e-mail standard "STANDARD FOR THE FOR FOR" which is currently widely used.
MAT OF ARPA INTERNET TEXT
MESSAGES "(RFC822). In the present embodiment, the common data file area 1
Email message in the file name created in Step 7.
Although the value itself of the e-ID field was used,
It is possible to use any file name where the value of the age-ID field is a key.

Embodiment 2 FIG. In the first embodiment, when a plurality of users receive a broadcast type e-mail on the same mail server, the e-mail to a part of the broadcast destination has a time delay via another mail server. One method for preventing the storage capacity of the storage device of the mail server from being wasted even when the mail server reaches the final delivery destination mail server is described. An embodiment will be described in which a recipient can recognize an electronic mail received via a route.

In the present embodiment, the configuration of the mail server is the same as that of FIG. 2 shown in the first embodiment, and the entire processing flow is the same as that of FIG. 3 shown in the first embodiment. The processing operations of new processing, additional processing, and read processing are different from those of the first embodiment. Note that in the following embodiments, the same parts as those in Embodiment 1 will be described using the same reference numerals.

FIG. 7 is a flowchart showing the operation of the new processing performed by the data storage processing means 16 in the present embodiment. The operation of this new process is as follows. When the new process is started (step S41), a file whose file name is the value of the Message-ID field is generated in the common data file area 17 (step S4).
2) The whole data including the header of the electronic mail is stored in this file (step S43). further,
The Message-ID field is stored in a file for each recipient in the individual data file area 18 (Step S44), and the process is terminated (Step S45).

FIG. 8 is a flowchart showing the operation of the additional processing performed by the data storage processing means 16 in the present embodiment. The operation of this additional processing is as follows. When the adding process is started (step S51), the message to the new recipient file in the individual data file area 18 is added to the message.
The e-ID field is stored (added) (step S5).
2) In addition, in the file of the new recipient in the individual data file area 18, the e-mail of the present reception with respect to the header of the data file identified by the value of the Message-ID field already existing in the common data file area 17. (Step S5).
3), the process ends (step S54).

FIG. 9 is a flowchart showing the operation of the reading process performed by the electronic mail reading means 19 in the present embodiment. The operation of the reading process is as follows. When the reading process is started (step S61), M is read from the file of the user in the individual data file area 18.
The message-ID is checked (step S62), and the message found in the common data file area 17 is searched.
-Read the e-mail from the file having the name of the value of the ID field (step S63). Next, from the individual file of the user in the individual data file area 18, the Me
The difference header corresponding to the message-ID is read (step S64), and both data obtained in steps S63 and S64 are sent to the user (step S6).
5), the process ends (step S66).

In the present embodiment, as described above, new processing, additional processing, and read processing are performed, so that the same text received via a different path from the previously received broadcast e-mail is transmitted. In the case of an e-mail that has an e-mail, since the difference information between the header of the e-mail received earlier and the header of the e-mail received later is clearly indicated to the user, the received e-mail passes through another mail server. The receiver can know additional or detailed information such as information received by the user on another mail server or retransmitted (Resent) from the user after being received by the user on another mail server.

Embodiment 3 Next, an embodiment will be described in which the e-mail is automatically deleted after all the recipients of the broadcast type e-mail on the same mail server have read the e-mail. In the present embodiment, the configuration diagram of the mail server is the same as FIG. 2 shown in the first embodiment, and the overall processing flow is the same as FIG. 3 shown in the first embodiment. The processing operations of the addition processing and the reading processing are different from those of the first embodiment.

FIG. 10 is a flowchart showing the operation of the new processing performed by the data storage processing means 16 in the present embodiment. The operation of this new process is as follows.
When the new process is started (step S71), the file name is Message-ID in the common data file area 17.
A file having a field value as a name is newly generated (step S72), a recipient list of the electronic mail is generated in the file (step S73), and the text of the electronic mail is stored (step S74). Next, the Mes is stored in the file for each recipient in the individual data file area 18.
Store the "sage-ID" field (step S7).
5), the process ends (step S76).

FIG. 11 is a flowchart showing the operation of the additional processing performed by the data storage processing means 16 in the present embodiment. The operation of this additional processing is as follows.
When the adding process is started (step S81), a new recipient is added to the recipient list in the file identified by the Message-ID field in the common data file area 17 (step S82), and the new recipient is added in the individual data file area 18. Message- in the new recipient's file
The ID is stored (step S83), and the difference information between the header of the electronic mail already stored in the common data area and the header of the electronic mail received this time is stored in the same file (step S84). The process ends (step S85).

FIG. 12 is a flowchart showing the operation of the reading process performed by the electronic mail reading means 19 in the present embodiment. The operation of the reading process is as follows. When the reading process is started (step S91), a Message-ID is checked from the file of the user in the individual data file area 18 (step S92), and the found Messagea in the common data file area 17 is checked.
An e-mail is read from a file having a name of the value of the “ge-ID” field (step S93).

Here, it is determined whether the user has designated deletion after reading when reading the electronic mail (step S94). If deletion has been designated, the usage in the individual data file area 18 is determined. The Message-ID in the individual file of the user is deleted (step S9).
5), the Message in the common data file area 17
The user is deleted from the recipient list in the file identified by the e-ID (step S96).

At this point, it is determined whether the recipient list is empty (step S97). If the recipient list is empty, the file containing the recipient list is deleted (step S98). If the deletion is not specified in step S94, the processing in steps S95 to S98 is not executed. If the recipient list is not empty in step S97, the processing in step S98 is not executed. Thereafter, the difference header is read from the file of the user in the individual data file area 18 (step S99), sent to the user together with the data read in step S93 (step S100), and the process is terminated (step S10).
1).

In the present embodiment, as described above, new processing, addition processing, and reading processing are performed, so that all recipients receiving the same broadcast e-mail on the same mail server specify deletion. Then, when the electronic mail is read, the file storing the electronic mail is deleted from the common data area, thereby preventing the read electronic mail from wasting capacity on the common data area. Becomes possible.

Embodiment 4 FIG. Next, an embodiment for managing a period during which a recipient stores an e-mail on a mail server will be described. In the present embodiment, the configuration diagram of the mail server is the same as that of FIG. 2 shown in the first embodiment, and the entire processing flow is the same as that of FIG. 3 shown in the first embodiment. The additional processing is the same as the processing described in the third embodiment, except for the processing operation of the reading processing.

FIG. 13 is a flowchart showing the operation of the reading process performed by the electronic mail reading means 19 in the present embodiment. The operation of the reading process is as follows. When the reading process is started (step S11)
1), a Message-ID is checked from the file of the user in the individual data file area 18 (step S11).
2) The e-mail is read from the file having the name of the Message-ID field found in the common data file area 17 (step S113).

Next, it is checked whether the period during which the e-mail is stored has passed the e-mail storage period preset for the user (step S11).
4) If not, it is further determined whether the user has designated deletion after reading when reading the e-mail (step S115).

Here, if deletion is designated, the Message-ID in the individual file of the user in the individual data file area 18 is deleted (step S11).
6), the Message in the common data file area 17
The user is deleted from the recipient list in the file identified by the e-ID (step S117). At this point, it is determined whether the recipient list is empty (step S118). If empty, the file containing the recipient list is deleted (step S119).

If the time limit has passed in step S114, the process in step S115 is skipped and step S115 is skipped.
The process proceeds to 116.

If the deletion is not specified in step S115, the process proceeds to step S120 without executing the processes in steps S116 to S119.
If the recipient list is not empty in step S118,
Step S120 is performed without executing the process of step S119.
Move to the processing of. Thereafter, the individual data file area 1
8, the difference header is read from the file of the user (step S120), sent to the user together with the data read in step S113 (step S121), and the process is terminated (step S122).

In the present embodiment, as described above, since the reading process is performed, even if the user of the e-mail forgets to specify the deletion, the e-mail server expires after a predetermined period. Since the e-mail stored in the mail server is automatically deleted, it is possible to prevent the storage capacity of the storage device of the mail server from being wasted due to the carelessness of the user.

Embodiment 5 Next, an embodiment for more efficiently operating the storage capacity of the storage device of the mail server will be described. FIG. 14 is a configuration diagram of the mail server according to the present embodiment. In FIG. 14, reference numeral 20 denotes a data type determining unit for determining the type of data stored in the e-mail, 21 denotes a data compressing unit that performs appropriate data compression in accordance with the data type, and 22 denotes a data type determining unit that matches the type of the compressed data. Data decompression means for performing appropriate data decompression.

FIG. 15 is a flowchart showing the operation of the new process performed by the data storage processing means 16 in the present embodiment, and FIG. 16 is a flowchart showing the operation of the read process performed by the electronic mail reading means 19 in the present embodiment. It is. In the present embodiment, the operations of the new process and the read process are different from those of the first embodiment.

Next, the operation of the new process according to the present embodiment will be described with reference to FIGS. When the data storage processing unit 16 starts a new process (step S13)
1) The data type determination unit 20 determines the type of the text data of the electronic mail, and determines a compression method appropriate for compression of this type and a file extension corresponding to the compression method (step S132).

Next, a file is generated in the common data file area 17 with the file name having the value of the Message-ID field and the extension determined previously (step S13).
3), a recipient list of the e-mail is generated in this file (step S134), and the data compression means 21 compresses the body data by a compression method corresponding to the extension (step S135). The header of the e-mail and the compressed body data are stored (step S1).
36). Subsequently, a Message-ID field is stored in each recipient file in the individual data file area 18 (step S137), and the operation is terminated (step S138).

Next, the operation of the reading process in this embodiment will be described with reference to FIGS. When starting the reading process (step S141), the e-mail reading means 19 checks the Message-ID from the file of the user in the individual data file area 18 (step S142), and is searched for in the common data file area 17. The e-mail is read from the file having the name of the Message-ID field as the name (step S14).
3). Here, the data decompression means 22 decompresses the compressed text data using a decompression method corresponding to the extension of the file (step S144).

Thereafter, it is checked whether the user has designated the deletion of the already-read mail (step S145). If the deletion has been designated, the deletion of the mail in the individual file of the user in the individual data file area 18 is performed. The Message-ID field is deleted (step S146), and the user is deleted from the list of recipients in the file having the Message-ID in the file name of the common data file area 17 (step S147). At this point, it is checked whether the recipient list is empty (step S148), and if it is empty, the file is deleted (step S149).

If it is determined in step S145 that the deletion has not been designated, steps S146 to S149 are performed.
Is not executed. If the recipient list is not empty in step S148, step S149 is not executed. Thereafter, the difference header of the individual data file area 18 is read (step S150), the header of the read e-mail, the decompressed text and the difference header are sent to the user (step S151), and the reading process is completed (step S150).
152).

As described above, according to the present embodiment, according to the type of data included in the broadcast e-mail,
Since the body data is compressed using the compression method having the highest compression efficiency, it is possible to further reduce the waste of the storage capacity of the storage device of the mail server. Also, since this compression method can be easily determined from the file extension even at the time of reading, the decompression means can be applied efficiently even at the time of reading. Furthermore, since no compression is performed on the header portion, the processing time in the difference header extraction processing does not change, and the overall processing time can be reduced as much as possible while performing compression.

In this embodiment, it is assumed that the text data is composed of a single data type. However, if the text data is composed of a plurality of data types, an appropriate compression method is applied to each data type. Can be easily handled by sequentially adding an extension corresponding to the file name after the file name.

Embodiment 6 FIG. In the fifth embodiment, the method of compressing the e-mail stored in the common data file area 17 by an appropriate means has been described. However, an embodiment for further reducing the communication amount between the user terminal and the mail server will be described. Show. In the present embodiment, the processing operation of the reading process is different from that of the fifth embodiment.

FIG. 17 is a flowchart showing the operation of the reading process performed by the electronic mail reading means 19 in the present embodiment. The operation of the reading process is as follows. When the reading process is started (step S
161), a Message-ID is checked from the file of the user in the individual data file area 18 (Step S)
142), reads out the compressed mail from the file having the name of the Message-ID field found in the common data file area 17 (step S16).
3). Here, it is checked whether the user has designated deletion (step S164). If deletion has been designated, the Message-ID field in the user's individual file is deleted (step S165), and the Message-I is deleted.
D, and deletes the user from the recipient list of the file in the common data file area 17 (step S1).
66), it is checked whether or not the recipient list is empty (step S167).

If the recipient list is empty, the Mes
Common data file area 1 identified by sage-ID
7 (step S168), a difference header is read from the user's file in the individual data file area 18 (step S169), and the read difference header and the compression format (identifier) of the compressed e-mail are read. )
To the user terminal in text mode (step S
170), the read compressed e-mail is transmitted to the user terminal in the binary mode (step S171), and the reading process is terminated (step S172).

If it is determined in step S164 that the deletion has not been designated, steps S165 to S16 are performed.
8 is not performed, and the process proceeds to step S169. If the recipient list is not empty in step S167, the process proceeds to step S169 without executing the process in step S168. The receiving terminal of the user decompresses the received compressed e-mail using the compression format received together with the difference header.

In the present embodiment, since the reading process is performed as described above, the data transfer from the mail server to the user's receiving terminal is performed as compressed data, so that the communication amount is reduced. Produces the effect of Although the present embodiment includes a method of deleting an electronic mail using a recipient list, it is needless to say that this function may not be included.

[0064]

Since the present invention is configured as described above, it has the following effects.

In the first invention, an identifier for identifying the text of the electronic mail is read from the electronic mail transmitted via the network, and the text of the transmitted electronic mail is stored in a file having the read identifier. First storage means, and second storage means for storing the identifier in a plurality of recipient files corresponding to each of a plurality of recipients receiving the e-mail text, wherein the reading means comprises An identifier for identifying the body of the e-mail to be transmitted from the storage unit is searched, the body of the e-mail in the file having the searched identifier is read from the file in the first storage unit, and the plurality of receptions are performed via a network. It is necessary to save the same e-mail text received by multiple recipients to a file for each recipient by sending it to the recipient's terminal Since there is no storage capacity, waste of storage capacity of the storage device can be prevented.

In the second invention, the difference in the transmitted route between the text of the e-mail stored in the file of the first storage means and the text of the transmitted e-mail is stored in the first storage. By transmitting to the terminals of a plurality of recipients via the network together with the text of the e-mail read from the file of the means, the received text of the e-mail is directly sent to the recipient of the mail server or transferred. The receiver can know whether the message has come.

In the third invention, a list of a plurality of recipients who receive the text of the e-mail is generated in the file of the first storage means, and the recipient who has received the text of the e-mail receives this list from the list of recipients. By deleting the recipient who received the email from the list of recipients, and deleting the file from which this list was generated when the list of recipients is exhausted. In addition, waste of the storage capacity of the storage device can be prevented.

In the fourth invention, it is checked whether the storage period of the electronic mail text has expired. If the storage period has expired, the recipient who received the electronic mail is deleted from the list of recipients, When the list is exhausted, the file from which the list was generated is deleted, so that the e-mail body stored after a certain period is automatically deleted, preventing wasting storage capacity of the storage device. it can.

In the fifth invention, the data type of the electronic mail text is determined, the data of the electronic mail text is compressed in accordance with the data type, and the compressed electronic mail text is stored in the first storage means. Stored in the file created inside,
When reading the electronic mail text, read the data of the compressed electronic mail text from the file in the first storage means;
By decompressing the compressed data, the data of the compressed e-mail text can be decompressed and returned to the original e-mail text, so that the storage capacity of the storage device can be prevented from being wasted.

In the sixth invention, the compressed electronic mail text read from the file in the first storage means and the extension determined by the storage processing means are transmitted to the terminals of the plurality of recipients via a network. By doing so, the amount of communication can be reduced.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of a mail server according to the first embodiment.

FIG. 3 is a flowchart showing an operation of the mail server in the first embodiment.

FIG. 4 is a flowchart showing an operation of a new process performed by the data storage processing unit in the first embodiment.

FIG. 5 is a flowchart showing an operation of an additional process performed by the data storage processing unit in the first embodiment.

FIG. 6 is a flowchart showing an operation of a reading process performed by the electronic mail reading means in the first embodiment.

FIG. 7 is a flowchart showing an operation of a new process performed by a data storage processing unit in the second embodiment.

FIG. 8 is a flowchart showing an operation of an additional process performed by a data storage processing unit in the second embodiment.

FIG. 9 is a flowchart showing an operation of a reading process performed by an electronic mail reading unit in the second embodiment.

FIG. 10 is a flowchart showing an operation of a new process performed by a data storage processing unit in the third embodiment.

FIG. 11 is a flowchart illustrating an operation of an additional process performed by a data storage processing unit according to the third embodiment.

FIG. 12 is a flowchart showing an operation of a reading process performed by an electronic mail reading unit in the third embodiment.

FIG. 13 is a flowchart showing an operation of a reading process performed by an electronic mail reading unit in the fourth embodiment.

FIG. 14 is a configuration diagram of a mail server according to the fifth embodiment.

FIG. 15 is a flowchart showing an operation of a new process performed by a data storage processing unit in the fifth embodiment.

FIG. 16 is a flowchart showing an operation of a reading process performed by the electronic mail reading means in the fifth embodiment.

FIG. 17 is a flowchart showing an operation of a reading process performed by an electronic mail reading unit according to the sixth embodiment.

FIG. 18 is a configuration diagram of a conventional electronic mail system.

[Explanation of symbols]

1 user-a terminal, 2 user-b terminal, 3 u
Ser-c terminal, 4 mail server A, 5 mail server B, 6 user-d terminal, 11 mail server, 12
Communication network, 13 electronic mail receiving means, 14 electronic mail transmitting means, 15 Message-ID analyzing means, 1
6 data storage processing means, 17 common data file area, 18 individual data file area, 19 e-mail reading means.

Claims (6)

[Claims] A first file storing an electronic mail body in a plurality of files having an identifier for identifying the electronic mail body;
Storage means for storing the identifier in a plurality of recipient files respectively corresponding to a plurality of recipients receiving the body of the e-mail; and e-mail transmitted via the network. Analysis means for reading an identifier for identifying the body of the e-mail and analyzing whether or not a file having the identifier exists in the first storage means; and storing the identifier in the first storage means by the analysis means When it is analyzed that a file having the following exists, the identifier is stored in the recipient file of the second storage means corresponding to the recipient who receives the text of the transmitted e-mail, and the first When it is analyzed that the file having the identifier does not exist in the storage means, a file having the identifier is newly created in the first storage means. The text of the transmitted e-mail is stored in this file, and the identifier is stored in a plurality of recipient files in the second storage means corresponding to the recipient who receives the transmitted e-mail text. A storage processing unit, and an identifier stored in the plurality of recipient files in the second storage unit, for searching for an identifier for identifying the body of the e-mail to be transmitted; Reading means for reading a mail text from the file in the first storage means and transmitting the read electronic mail text to the terminals of the plurality of recipients via a network. system. 2. The electronic mail stored in the file of the first storage means when the analysis means analyzes that the file having the identifier exists in the first storage means. The difference between the transmitted route of the text and the transmitted text of the e-mail is stored in the second storage means, and the reading means is stored in the recipient file of the second storage means. 2. The electronic device according to claim 1, wherein the transmitted route difference is transmitted to terminals of the plurality of recipients via a network together with an electronic mail text read from a file in the first storage means. Mail system. 3. The storage processing means generates, in a file of the first storage means, a list of a plurality of recipients who receive an e-mail text, and the reading means generates a list of recipients who received the e-mail text. Determines whether the recipient has been designated to be deleted from the list of recipients. If the designation has been made, the reception corresponding to the recipient who received the e-mail text in the second storage means is determined. Deletes the identifier in the recipient file, deletes the recipient who received the email from the list of recipients, and deletes the file from which the list was generated when the list of recipients is exhausted The e-mail system according to claim 1, wherein: 4. The reading means checks whether the storage period of the e-mail text set by the recipient has expired, and when the storage period has expired, receives the e-mail text in the second storage means. Delete the identifier in the recipient file corresponding to the recipient, and delete the recipient who received the e-mail from the list of recipients,
4. The electronic mail system according to claim 3, wherein when all of the list of the recipients is lost, the file in which the list is generated is deleted. 5. A data type judging means for judging a data type of an electronic mail text, a data compressing means for compressing data of an electronic mail text in accordance with the data type, and a compressed data of the electronic mail text. Data decompression means for decompressing the data, the storage processing means determines a method of compressing the data of the e-mail text based on the data type of the e-mail text determined by the data type determination means, A file having a file extension indicating a method and an identifier for identifying an e-mail text is created in the first storage means, and the data of the e-mail text compressed by the data compression means is stored in the created file. The reading means reads the compressed e-mail text stored in the file of the first storage means, and reads the read compressed e-mail text. E-mail system according to claim 4, characterized in that decompressed by the data decompression section based on the e-mail text into a file extension of the file of the first storage means. 6. The reading means reads out a compressed electronic mail text stored in a file of the first storage means, and reads the compressed electronic mail text and an extension determined by the storage processing means. The e-mail system according to claim 5, wherein the e-mail is transmitted to terminals of the plurality of recipients via a network.