JP2000216807A - Electronic mail delivering system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent tapping by a third party on a transmission path in the transmission/reception of an electronic mail. SOLUTION: Plural servers for transferring electronic mails 7 are distribute- arranged on a network. A transmission source 5 divides a group of messages to prepare plural electronic mails and sends respective electronic mails to a receiving destination 6 via respective servers 8 to 10 for transferring electronic mails to separate transmission routes. The destination 6 combines fragmentary messages brought by the plural electronic mails to restore the original message.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic mail delivery system, and more particularly, to preventing the contents of an electronic mail being transmitted and received by a third party from being read even if the eavesdropping is performed by a third party. Means to do.

[0002]

2. Description of the Related Art In recent years, one of services used on the Internet is an e-mail service. An e-mail service is a service for exchanging electronic messages with specific people on the Internet. When using this e-mail service, software generally called a mailer is used to create, transmit and receive e-mails. The e-mail to be created contains the e-mail address of the recipient, the title, the e-mail address of the sender, the body (message) of the e-mail, the attached file, and the like. This will be described with reference to the drawings.

FIG. 8 is a conceptual diagram showing a configuration example of an electronic mail. The e-mail shown in this example has a header 1 in which a destination mail address (To), a title (Subject), and a source mail address (From) are described.
And a body part 2 in which the body of the e-mail is described, and a blank line part 3 wrapping the header part 1 and the body part 2 to form an outer frame as one e-mail. If there is an attached file, it is often stored in the body.

[0004] In a conventional general electronic mail transmission / reception, first, a sender creates an electronic mail as shown in FIG. 8 using a mailer and sends it to a mail server. The mail server is a server that provides a function corresponding to an electronic mail box (mail box) of a person who uses an electronic mail on a network, and executes a process of transmitting and receiving an electronic mail. The sending mail server that receives the e-mail sent from the sender's terminal sends the e-mail to the receiving mail server connected to the network based on the receiving e-mail address in the e-mail header. send an email. When the receiving mail server receives the e-mail, it holds the e-mail, and the recipient transmits the message by referring to the mail server.

[0005] In actual transmission and reception of electronic mail, packets are divided and transmitted as packets prescribed in a network, and each packet is guided to a target destination by a router on the network. For example, in the case of an e-mail using the Internet, a delivery route is determined by a router on the Internet based on the destination information in the header section 1, and the mail is finally delivered to the destination while repeating copying and deletion between the routers. It has a mechanism. In addition, there are strict rules for the data format of the email, and the mailer composes the email, communicates with the mail server, and the like based on the rule. That is, in the process of sending and receiving an e-mail, various data conversions are performed, and the receiving destination (refers to the terminal of the receiver and the mail server on the receiving side)
Performs the reverse of the procedure performed by the sender (which indicates the sender's terminal and the sending mail server).

[0006]

However, the above-mentioned conventional electronic mail delivery system has the following problems. In other words, in an electronic mail delivery system using a public network that can be freely accessed by an unspecified number of people, such as the Internet, the mail content is divided into packets as they are and sent.
If a person observes the packet on the transfer path, he / she can peek at the mail contents of another person. That is, there is a problem that contents that the third party does not want to be seen by a third party, such as a credit card number and confidential information, cannot be exchanged by e-mail. Although data encryption is commonly used to make up for this problem, it remains easy for eavesdroppers to capture the encrypted e-mail.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it has been made difficult for a third party who attempts to eavesdrop on to capture the full text of an electronic mail, thereby preventing the contents from being decoded. The purpose is to provide an electronic mail delivery system.

[0008]

According to a first aspect of the present invention, there is provided an electronic mail delivery system according to the present invention, wherein a plurality of electronic mail transfer servers are distributed on a communication network connected in a network. An e-mail delivery system for arranging and transmitting / receiving e-mails, wherein a group of messages is divided into a plurality of messages, each of the divided messages is converted into an e-mail, and each e-mail is sent to a separate e-mail transfer server And a destination for combining a plurality of incoming e-mails transferred by the e-mail transfer server and restoring the original message, and distributing the route in a distributed manner. The invention of claim 2 of the electronic mail delivery system according to the present invention is characterized in that, in the electronic mail delivery system according to claim 1, a message is scrambled by a transmission source and a message is descrambled by a reception destination. And

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments. FIG. 1 is a functional block diagram showing an embodiment of an electronic mail delivery system according to the present invention.

The e-mail delivery system shown in this example is:
In a network formed by connecting a plurality of routers 4 in a net-like manner, a transmission source 5, a reception destination 6, and e-mail transfer servers (transfer servers) 7 to 10 are connected via respective routers. I have. At this time, the sender 5 and the receiver 6
Transfer servers 7 to 10 for a plurality of routes connecting
It is preferable to configure the system so that each is distributed. Here, the sender 5 and the receiver 6 refer to an area of a sender or a receiver including a terminal to a mail server, respectively.

The electronic mail delivery system shown in this figure functions as follows. That is, when sending an e-mail from the transmission source 5 to the reception destination 6, the transmission source 5 divides the whole message to be transmitted to the reception destination 6 into several parts,
E-mail each of the divided messages to create multiple e-mails. Then, for each e-mail, a destination of a different transfer server is added and transmitted so as to be stacked on the destination of the destination 6 which is the final target. Since the plurality of divided e-mails reach the destination 6 via different transfer servers, these e-mails are sent by different routes.

Next, an e-mail transmission procedure at the transmission source 5 will be described with reference to a flowchart. FIG. 2 is a flowchart showing an example of an e-mail transmission procedure at the transmission source of the e-mail delivery system according to the present invention. First, a sender composes a message using a mailer. (ST1) The created message is scrambled.
(ST2) The scrambled message is divided. (ST
3) In this example, the image is divided into A, B, and C. Each of the divided messages is converted into an electronic mail to create an electronic mail. (ST4) A separate transfer server destination is added to each of the electronic mails. (ST5) The e-mail to which the destination of the transfer server is added is transmitted. (ST6) When the work up to this point is performed, the transmission process of the transmission source ends, and a standby state (hereinafter, referred to as an idle state) is established. (ST
7)

Next, an actual image based on the above-described transmission procedure will be described with reference to the drawings. FIG. 3 is a diagram showing an example of an electronic mail transmission image at the transmission source of the electronic mail delivery system according to the present invention. In the example shown in this figure, a case where short words are scrambled is illustrated for the sake of simplicity. That is, first, it created "Hello." Scrambles the message the sentence "Nniko. Eight" and it is divided into three parts after. For convenience of explanation, the divided messages are separately shown as A to C, and A is divided into "n", B is "ko", and C is divided into "ha". Each of the three divided messages is added to a header designating the address of the destination 6 which is the final destination, and is converted into an electronic mail. Next, a header specifying the destination of the transfer server to be passed on the way to the destination 6 is added. A is added with a header specifying the destination of the transfer server 7, B is added with a header specifying the destination of the transfer server 8, and C is added with a header specifying the destination of the transfer servers 10 and 9. I have. Note that C
Is a case where two transfer servers to be passed are specified, and in this case, two headers are added.

The manner in which the above-described electronic mail header is added will be described with reference to FIG. FIG. 4 is a diagram showing an example of an image when a header is added to a divided e-mail at the transmission source of the e-mail delivery system according to the present invention. The example shown in this figure will be described with reference to the divided message A shown in FIG. When a header is added to an e-mail 13 composed of a header 11 in which the address of the destination 6 which is the final purpose is specified, and a body 12 storing the divided message “nni”, the e-mail 13 is added to the body 14. Then, a header 15 in which the address of the transfer server 7 is specified is added to the
Is created. In other words, the header of the e-mail is superimposed as if the envelope were placed inside the envelope.

The electronic mail transmitted from the transmission source 5 to the network in this manner is sent to the transfer server specified for each destination. Next, the transfer procedure of the transfer server will be described using a flowchart. FIG. 5 is a flowchart showing an example of an e-mail transfer procedure in the e-mail transfer server of the e-mail delivery system according to the present invention. First, an e-mail arrives at the e-mail transfer server in the idle state (ST8) and is received. (ST
9) The e-mail transfer server deletes the destination information addressed to itself from the received e-mail. (ST10) That is,
The header is deleted by a procedure reverse to the addition of the header shown in FIG. Then, the e-mail transfer server transmits the e-mail based on the next destination specified in the header of the e-mail from which the header addressed to itself has been deleted (ST1).
1) Return to the idle state. (ST12)

The e-mail transferred by the transfer server eventually reaches the final destination 6. The receiving procedure of the receiving source will be described using a flowchart. FIG. 6 is a flowchart showing an example of an e-mail receiving procedure at the receiving end of the e-mail delivery system according to the present invention. i
The e-mails A, B, and C divided and transmitted to the destination 6 in the dle state (ST13) arrive at the destination 6 through different routes. (ST14) Recipient 6
Extracts messages split into each of the three emails and combines them. (ST15) Since scrambling has been applied at the transmission source, descrambling is performed. (ST16) The original message is restored, and the recipient can understand the message. (ST17)

In the "combine" process in step ST15, clues are required when actually combining, but the means may be as follows, for example. For example, if the sender 5 assigns a serial number of AAA to the full text of the created message and divides the serial number into three, each of the three electronic mails created as “AAA”
A-1 / 3 "," AAA-2 / 3 ", and" AAA-3 /
3 ”and send it. Recipient 6
Based on the fact that the sender address is the sender 5 and the identification number, the electronic mails may be classified, arranged in order, and combined.

Next, an actual image of the receiving procedure will be described with reference to the drawings. FIG. 7 is a diagram showing an example of an e-mail reception image at a reception destination of the e-mail delivery system according to the present invention. The destination 6 shown in this example functions as follows. That is, the divided messages are extracted from the electronic mails A, B, and C that arrive separately from each other.
More specifically, using the identification number as a clue, “nni” is sent from the e-mail of A, and “ko.” Is sent from the e-mail of B.
Is extracted from the e-mail of C, and these are arranged in order and combined. Then, by performing descrambling opposite to the scrambling performed at the transmission source 5, the entire original original message is restored.

In the above-described embodiment of the present invention, an example has been described in which scrambling is performed at the transmission source and descrambling is performed at the reception destination. However, the present invention is not limited to this example. For example, encryption and scrambling may be used together. According to this, the confidentiality of the divided message can be improved.

As described above, the electronic mail delivery system according to the present invention can capture only a fragmentary electronic mail even if a third party attempts eavesdropping at one point on the network. Email fragments are scrambled and cannot be understood. Furthermore, even if a third party attempts eavesdropping at a plurality of points on the network, since the network is configured in a net-like form, the number of routes becomes enormous, and it is known which of these routes was used for transmission. Because it is only the sender, it is very difficult to capture all the divided emails.

[0021]

As described above, the e-mail delivery system according to the present invention divides a group of messages and delivers them by different routes, which makes it difficult for a third party to decipher the eavesdropping, and makes the e-mail delivery difficult. It has a remarkable effect in increasing the confidentiality of the information.

[Brief description of the drawings]

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

FIG. 2 is a flowchart showing an example of an e-mail transmission procedure at a transmission source of the e-mail delivery system according to the present invention.

FIG. 3 is a diagram showing an e-mail transmission image at the transmission source of the e-mail delivery system according to the present invention.

FIG. 4 is a diagram showing an image when a header is added to a divided e-mail at the transmission source of the e-mail delivery system according to the present invention.

FIG. 5 is a flowchart showing an example of an e-mail transfer procedure in the e-mail transfer server of the e-mail delivery system according to the present invention.

FIG. 6 is a flowchart showing an example of an e-mail receiving procedure at a destination of the e-mail delivery system according to the present invention.

FIG. 7 is a view showing an image of an e-mail reception at a destination of the e-mail delivery system according to the present invention.

FIG. 8 is a diagram showing a configuration example of a general electronic mail;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Header part 2 ... Body part 3 ... Blank line part 4 ... Router 5 ... Sender 6 ... Reception destination 7-10 ... E-mail transfer server 11 ...・ Header 12 ・ ・ ・ Body 13 ・ ・ ・ Email 14 ・ ・ ・ Body 15 ・ ・ ・ Header 16 ・ ・ ・ Email

Claims (2)

[Claims] 1. An electronic mail delivery system for transmitting and receiving electronic mail by distributing a plurality of electronic mail transfer servers on a communication network connected in a network, wherein the message is divided into a plurality of pieces. And converting at least one of the plurality of e-mails into an e-mail
A source for sending one to another e-mail transfer server, a destination for combining a plurality of incoming e-mails transferred by the e-mail transfer server, and restoring the original message; An electronic mail delivery system characterized in that the electronic mail is distributed and delivered. 2. The electronic mail delivery system according to claim 1, wherein the message is scrambled at the transmission source and then divided into a plurality of parts, and the combined message is descrambled and restored at the destination.