JP4414872B2 - Message communication system - Google Patents

Description

  The present invention relates to a message communication system that communicates message data such as electronic mail via a wireless line, and more particularly to a message communication system that improves communication efficiency in a wireless line.

For example, message data such as e-mail is transmitted and received, and a wireless line is also used.
FIG. 9 shows an example of an electronic mail communication system.
In the e-mail communication system of this example, e-mail data created by a MUA (Mail User Agent) 21 is transmitted by a MTA (Message Transfer Agent) 22. The e-mail data is received by the MTA 23 and viewed by the destination MUA 24, and is received by the MTA 25 via the wireless devices 31 and 32 and viewed by the destination MUA 26.
Here, in the wireless communication between the wireless devices 31 and 32, the SMTP (Simple Mail Transport Protocol) protocol is executed. As described above, in general, when sending and receiving e-mails by wireless communication, a method in which a wireless line is regarded as a wired LAN (Local Area Network) and the SMTP protocol is directly passed is used.

FIG. 10 shows an example of processing of the SMTP protocol, and shows an example of a procedure in which various types of information are communicated between the transmission side and the reception side.
As shown in FIG. 10, in the SMTP protocol, one e-mail is divided into a plurality of lines, and each time one line of data is transmitted from the SMTP server on the transmission side to the SMTP server on the reception side, A response is sent from the SMTP server to the sending SMTP server. In this example, during one e-mail transmission, information is exchanged between the sending-side SMTP server and the receiving-side SMTP server about 11 times in addition to sending the mail text.
For this reason, there is a problem that the communication time required for wireless communication becomes long. For example, when the wireless line is high-speed and not inferior to a wired LAN, there is no problem even with the above-mentioned method, but especially when using a low-speed wireless line, Such a large number of exchanges (about 11 in the above case) is very wasteful.

Further, when one e-mail is transmitted to a plurality of destinations, the mail text may be duplicated by the number of destinations in the process of delivering the e-mail between the SMTP servers. If the destination address belongs to the same domain, and that domain is a partner to send via a wireless line, several e-mails with the same mail text but different only in the destination will be sent.
For this reason, there is a problem that the communication time required for wireless communication becomes long.

  As an example of the prior art, the message wireless communication apparatus accepts a transmission data limit value from a user, divides message data to be transmitted based on the limit value into a plurality of message data, and these divided message data Is transmitted wirelessly (see, for example, Patent Document 1).

JP 2002-140247 A

As described above, in an electronic mail communication system, transmission efficiency (communication efficiency) in a wireless line has deteriorated. Specifically, for example, in an electronic mail communication system, there is a problem in that transmission efficiency deteriorates because the SMTP protocol is directly passed through a wireless line. In addition, for example, in an electronic mail communication system, there is a problem in that transmission efficiency deteriorates because an electronic mail with the same mail text but different destinations is sent to the same domain by the number of destinations via a wireless line. there were.
The present invention has been made to solve such a conventional problem, and a message capable of improving communication efficiency in a wireless line when communicating message data such as an electronic mail via the wireless line. An object is to provide a communication system.

In order to achieve the above object, the message communication system according to the present invention communicates message data using wireless communication as follows.
That is, on the transmitting side, the transmitting means transmits the message data by SMTP, the packet generating means adds destination information to the transmitted message data to generate a packet, and the wireless transmitting means generates the generated packet. Is transmitted wirelessly. On the receiving side, the wireless receiving means receives the wirelessly transmitted packet, the reproducing means deletes the destination information from the received packet to reproduce the message data, and the receiving means reproduces the reproduced message. Are received by SMTP.
Accordingly, since message data transmitted by SMTP is packetized and transmitted instead of SMTP in wireless communication, communication efficiency in the wireless line can be improved when communicating message data via the wireless line. it can.

Here, in the message communication system, a wireless line (wireless communication) is used for a part or all of a route for transmitting message data.
As the message data, for example, various kinds of data such as e-mail may be used.
The sending means includes means for creating message data by being operated by a person (user), for example, and means for sending out the created message data by SMTP.
The receiving means includes, for example, means for receiving message data by SMTP, and means for outputting the received message data to a person (user) by screen display.

The packet is configured by adding destination information including information on a transmission source and a transmission destination as a header to message data, for example. In this case, various information may be included in the header, and all or part of the message data may be used as message data.
The destination information added to the packet is used only in wireless communication, for example, added on the wireless communication transmission side, and deleted on the wireless communication reception side.
In packet wireless communication, for example, a packet may be divided into a plurality of blocks, and transmission or retransmission may be performed for each block.

In the message communication system according to the present invention, the following processing is performed as a configuration example.
In other words, the packet generation unit generates one packet including information on a plurality of destinations from data of a plurality of messages having different destinations only. When the received packet includes information on a plurality of destinations, the reproducing unit reproduces data of a plurality of messages having only different destinations from the packet.
Accordingly, data of a plurality of messages having different destinations are not wirelessly communicated separately, but are wirelessly communicated in a form in which they are collected. Therefore, when communicating message data via a wireless line, Communication efficiency on the line can be improved.

Here, various numbers of two or more may be used as the number of data of a plurality of messages to be wirelessly communicated together.
Also, the information of the plurality of destinations is included in, for example, a header added to the packet on the wireless communication transmission side, and is deleted on the wireless communication reception side.
On the wireless communication transmitting side, data of a plurality of messages that differ only in destination are collectively transmitted, and on the wireless communication receiving side, the data of the original plurality of messages is reproduced from the received packet.

As described above, according to the message communication system according to the present invention, on the transmission side, for example, message data created by a terminal device or the like is transmitted by SMTP, and destination information is added to the data of the transmitted message. The packet is generated and transmitted by wireless, and the receiving side receives the wirelessly transmitted packet, deletes the destination information from the packet, reproduces the message data, and reproduces the packet. Since the message data is received by, for example, a terminal device via SMTP, the communication efficiency in the wireless line can be improved when the message data is communicated via the wireless line.
Further, according to the message communication system according to the present invention, on the transmitting side, one packet including information on the plurality of destinations is generated from the data of a plurality of messages that are different only in the destination, and wirelessly transmitted. On the receiving side, When the received packet includes information on a plurality of destinations, since the data of a plurality of messages that differ only in the destination is reproduced from the packet, when communicating the data of the messages via a wireless line, Communication efficiency in a wireless line can be improved.

An embodiment according to the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration example of an electronic mail communication system which is a message communication system according to an embodiment of the present invention.
The e-mail communication system of this example includes, as processing units on the transmission side in this example, MUA (first MUA) 1, MTA (first MTA) 2, MTA (second MTA) 3, A processing unit that includes a transmission box (first transmission box) 4, a reception box (first reception box) 5, and a wireless device (first wireless device) 6, and serves as a reception side in this example. Wireless device (second wireless device) 11, transmission box (second transmission box) 12, reception box (second reception box) 13, MTA (third MTA) 14, and MTA ( 4th MTA) 15 and MUA (2nd MUA) 16 are provided.
Here, in this example, the processing unit on the transmission side and the processing unit on the reception side will be described separately, but each of these processing units has both a function on the transmission side and a function on the reception side. That is, it has a function of transmitting / receiving e-mail data.

The first MUA 1 and the second MUA 16 have a function of reading and writing e-mail, and are provided, for example, in a terminal device such as a stationary or portable computer or a mobile terminal device. In the terminal device provided with the MUAs 1 and 6, for example, a person (user) inputs various information by operating a key of the terminal device or information such as an e-mail displayed on the screen of the terminal device. You can browse.
In this example, the sender's domain address is bbb. com, and the address of the first MUA1 is 222 @ bbb. com and the domain address on the receiving side is ccc. com, and the address of the second MUA 16 is 333 @ ccc. com.

The first MTA 2 and the fourth MTA 15 have a function of transmitting / receiving e-mail data, and are provided in a terminal device such as a computer, for example.
In this example, as the first MTA 2 and the fourth MTA 15, for example, functions similar to those of a conventional SMTP server are used.
Note that the first MUA 1 and the first MTA 2 may be provided in the same device or may be provided in different devices. Similarly, the second MUA 16 and the fourth MTA 15 may be provided in the same device, or may be provided in different devices.

The second MTA 3 and the third MTA 14 have a function of transmitting / receiving e-mail data and a function of controlling the wireless devices of the wireless devices 6 and 11 (wireless device control function). It is provided in the terminal device.
In this example, as the second MTA 3 and the third MTA 14, for example, a function in which a radio control function is added to the same function as that of a conventional SMTP server is used.
The 1st transmission box 4 and the 2nd transmission box 12 are comprised, for example from memory, and memorize | store the data of the email used as transmission object.
The first receiving box 5 and the second receiving box 13 are constituted by a memory, for example, and store received e-mail data.
The first wireless device 6 and the second wireless device 11 include a wireless device and an antenna, and have a function of communicating data via a wireless line.

An example of the operation performed in the electronic mail communication system of this example will be shown.
The operation on the transmission side will be described.
E-mail data (e-mail file) addressed to the second MUA 16 (addressed to address 333@ccc.com) created by the first MUA 1 is first transferred from the first MUA 1 to the first MTA 2 using the SMTP protocol. Sent.
The first MTA 2 detects that the e-mail is to be delivered to the second MTA 3 from the destination address (333@ccc.com) of the received e-mail, and again transmits the e-mail data to the SMTP protocol. To the second MTA 3.
The second MTA 3 adds e-mail data received from the first MTA 2 to a file by adding, for example, destination address information or source address information as predetermined destination information to a file, and stores the file in the first transmission box. accumulate.
Here, FIG. 2 shows an example of the format of e-mail data. The e-mail data in this example is composed of the source address, destination address, e-mail title, one blank line before the e-mail text, the e-mail text, and the line containing only the period indicating the end of the e-mail. ing.

Further, the radio equipment control function of the second MTA 3 periodically checks (checks) whether or not an e-mail file exists in the first transmission box 4, and if an e-mail file exists. The electronic mail file is transmitted (transferred) to the wireless device of the first wireless device 6.
At this time, if there are a plurality of e-mail files in the first transmission box 4, the radio control function of the second MTA 3 performs the transmission source address (From :) in the e-mail file shown in FIG. Continuing information), e-mail title (information following Subject), and mail body content (information between one blank line and a line with only a period) are compared between different e-mails, all of which match. When there are two e-mail files, the destination address (information following To :) of one e-mail file is added as information of the destination address of the other e-mail file, and the one e-mail file is added. Delete from the first transmission box 4.
Here, these two e-mail files are e-mails having the same source address, e-mail title, and e-mail text, and different only in the destination address. Email files are combined into one email file. In this example, the configuration in which the process of combining two electronic mail files is repeated has been described, but the process of combining three or more electronic mail files may be performed.

Further, the radio control function of the second MTA 3 divides the e-mail file acquired as described above into smaller blocks, and converts them into a format in which a header is added to the head of each block.
FIG. 3 shows an example in which an email file having a plurality of destination addresses is divided into a plurality of blocks # 1 to #n and headers # 1 to #n are added to the heads of the blocks # 1 to #n. It is shown.
As the header of each block, a block number and a block error detection code are added.

By adding this error detection code, a transmission error in the radio space can be detected on the receiving side in units of blocks. In this example, the reception side notifies the transmission side of the block number of the block in which the transmission error is detected, and the transmission side transmits (retransmits) the notified erroneous block again. Such retransmission control is repeated until there are no erroneous blocks.
FIG. 4 shows an example of retransmission control processing. In this example, when the header and block information of # 1 to # 6 are transmitted from the transmission-side wireless device 6 to the reception-side wireless device 11, the reception-side wireless device 11 transmits to the transmission-side wireless device 6 #. The fact that an error has been detected is notified for 2 and # 5, and in response, the header and block information for # 2 and # 5 are retransmitted from the transmitting-side wireless device 6 to the receiving-side wireless device 11.

The operation on the receiving side will be described.
The e-mail data transmitted from the transmitting side via the wireless line is received by the receiving side, and the received e-mail data is sent to the destination information (information on the destination address and the destination address by the radio control function of the third MTA 14). The information of the transmission source address) is removed to form an e-mail file, which is stored in the second inbox 13.
At this time, when a plurality of transmission destination addresses are set in the destination information, the wireless device control function of the third MTA 14 has a plurality of electronic mail files in which the transmission source address, the mail title, and the mail body are the same. A duplicate of the received e-mail file is created so as to be created in the same number as that of the destination address, and this is stored in the second inbox 13.

The SMTP server function of the third MTA 14 periodically checks (checks) whether there is an e-mail file in the second inbox 13, and if the e-mail file exists, the SMTP server function uses the SMTP protocol. The mail file is delivered to the fourth MTA 15.
Since the received M-mail file is under the domain of its own domain (ccc.com), the fourth MTA 15 uses the received one or more e-mail files as their respective addresses. Store in a box.
The second MUA 16 obtains an e-mail file addressed to itself from its own mailbox using, for example, the POP3 protocol.

Next, with reference to FIGS. 5 to 8, an example of a procedure of processing performed in the electronic mail communication system of this example will be described.
FIG. 5 shows an example of a processing procedure performed by the SMTP protocol function of the MTA 3 on the transmission side.
First, it is determined whether there is a connection request to the SMTP server from the MUA1 and MTA2 side on the transmission side (step S1), and if there is a connection request, e-mail data is acquired by the SMTP protocol (step S1). S2). Then, the destination information is added to the acquired e-mail data and stored in the transmission box 4 (step S3).

FIG. 6 shows an example of a procedure of processing performed by the wireless device control function of the transmitting side MTA 3.
First, it is determined whether or not an e-mail file is stored in the transmission box 4 (step S11). If it is stored, it is determined whether or not a plurality of e-mail files are stored in the transmission box 4. (Step S12) If it is stored, it is determined whether or not the transmission source address, the mail title, and the mail text match for the plurality of electronic mail files (Step S13). For a plurality of e-mail files that match, the destination addresses of one e-mail file are added to the destination addresses of the other e-mail files and are combined into one (step S14).
After the above processing is completed, the e-mail file existing as a transmission target is divided into blocks, and a header is added to each block (step S15). Then, the data of each block is transmitted (step S16).
When information on the error block is received from the receiving side (step S17), it is determined whether there is an error block based on the content of the information (step S18). The block is retransmitted (step S19).

FIG. 7 shows an example of the procedure of processing performed by the radio control function of the MTA 14 on the receiving side.
When reception of a signal from the transmission side is detected (step S21), processing for establishing synchronization with the transmission side is performed (step S22). After the synchronization is established, a process for determining whether or not all the block data transmitted from the transmission side has been received (step S23). If all the block data has not been received, one block of data is received. Process for determining whether or not the reception block has been completed (step S24), and processing for determining whether or not there is an error in the reception block when reception of one block of data has been completed (step S25). If there is, the process of saving the error block number by storing it in the memory (step S26) is repeated until data of all blocks is received from the transmission side.

When all blocks of data have been received from the transmission side (step S23), it is determined whether or not there is an error block (step S27). If there is an error block, the error block number is read from the memory. The data is transmitted to the transmission side (step S28), and the same reception processing (steps S23 to S28) as described above is performed on the data retransmitted from the transmission side for the error block.
Further, when all blocks of data have been received from the transmission side and there are no error blocks from the beginning, or when they have been lost due to retransmission (step S27), the destination information of the e-mail file composed of the plurality of received blocks It is determined whether or not a plurality of destination addresses are stored (step S29). If a plurality of destination addresses are stored, the same number of e-mail files as the destination addresses are stored. A copy of the file is created (step S30).
If only one destination address is included in the destination information of the received e-mail file, the e-mail file is stored in the inbox 13, and the destination information of the received e-mail file includes a plurality of destination information. If the destination address is included, an e-mail file in which the destination address is collected is stored in the receiving box 13 (step S31).

FIG. 8 shows an example of a processing procedure performed by the SMTP protocol function of the MTA 14 on the receiving side.
It is determined whether there is an e-mail file in the reception box 13 (step S41). If there is, the e-mail file is delivered to the SMTP server by the SMTP protocol (step S42).

As described above, in the electronic mail communication system of this example, when an electronic mail is transmitted / received by wireless communication using the wireless communication system, the electronic mail is sent without performing the SMTP protocol processing on the wireless line. Transmission / reception is performed as one packet.
Further, in the electronic mail communication system of this example, when an electronic mail is transmitted and received using a wireless communication system, an electronic mail in which a plurality of destinations in the same domain are designated is divided for each destination. Sending and receiving with a plurality of destinations added to the mail text is performed without transmission.

Therefore, in the e-mail communication system of this example, it is possible to send an e-mail as a single packet on the wireless line using a protocol specific to this example. For example, the SMTP protocol is implemented on the wireless line. Compared to the case, the electronic mail can be sent faster and the transmission time can be shortened. Also, the transmission time can be shortened by sending a plurality of e-mails with different destination addresses in the same domain as one e-mail and a plurality of address information. In this example, retransmission control is performed when a transmission error occurs.
As described above, in the electronic mail communication system of this example, it is possible to reduce the communication time by performing wireless communication using a protocol capable of sending the mail text at one time, and the same mail text is used. The communication time can be reduced by sending only a plurality of destination information and a single mail text for a plurality of e-mails that are different only in the destination, so that a wireless communication system comprising the wireless devices 6 and 11 can be used. When sending and receiving e-mail, the e-mail can be efficiently delivered via a wireless line.

Here, a specific example of the effect obtained by the electronic mail communication system of this example is shown.
For example, if the wireless communication speed on the wireless line is 9600 bps and it takes 500 ms to establish synchronization on the receiving side, the SMTP protocol shown in FIG. 10 will send an e-mail of 1 kbyte. In contrast to the transmission time of 7548 ms, in the method of this example, when an e-mail having the same conditions as described above is transmitted, the transmission time is 1356 ms, and the transmission time can be about 1/5. In addition, when a plurality of e-mails having different destination addresses only in the same domain are sent as one e-mail and a plurality of address information, the e-mail can be sent with a transmission time of about (1 / the plurality). .

Note that, on the transmission side of the e-mail communication system of this example, the transmission means is configured by the function of the first MUA1 and the function of the first MTA2, and the packet generation means is configured by the function of the second MTA3. The wireless transmission means is configured by the function of the second MTA 3 and the function of the first wireless device 6. The function of the first transmission box 4 and the first reception box 5 constitutes a means for storing data.
Further, on the receiving side of the e-mail communication system of this example, a wireless receiving means is configured by the function of the second wireless device 11, and a reproducing means is configured by the function of the third MTA 14, and the second means The receiving means is constituted by the function of the MUA 16 and the function of the fourth MTA 15. The function of the second transmission box 12 and the second reception box 13 constitutes a means for storing data.

Here, the configuration of the message communication system and each device according to the present invention is not necessarily limited to the above-described configuration, and various configurations may be used. The present invention can also be provided as, for example, a method or method for executing the processing according to the present invention, a program for realizing such a method or method, or a recording medium for recording the program. It is also possible to provide various devices and systems.
The application field of the present invention is not necessarily limited to the above-described fields, and the present invention can be applied to various fields.
In addition, as various processes performed in the message communication system and each device according to the present invention, the processor executes a control program stored in a ROM (Read Only Memory) in a hardware resource including a processor, a memory, and the like, for example. The configuration controlled by doing so may be used, and for example, each functional means for executing the processing may be configured as an independent hardware circuit.
The present invention can also be understood as a computer-readable recording medium such as a floppy (registered trademark) disk or a CD (Compact Disc) -ROM storing the control program, and the program (itself). The processing according to the present invention can be performed by inputting the program from the recording medium to the computer and causing the processor to execute the program.

It is a figure which shows the structural example of the electronic mail communication system which concerns on one Example of this invention. It is a figure which shows an example of the format of electronic mail data. It is a figure which shows an example of the block division | segmentation of an email file. It is a figure which shows an example of the process of retransmission control. It is a figure which shows an example of the procedure of the process performed by the SMTP protocol function of a transmission side. It is a figure which shows an example of the procedure of the process performed by the radio | wireless machine control function of a transmission side. It is a figure which shows an example of the procedure of the process performed by the radio | wireless machine control function of a receiving side. It is a figure which shows an example of the procedure of the process performed by the SMTP protocol function on the receiving side. It is a figure which shows the structural example of an electronic mail communication system. It is a figure which shows an example of a process of SMTP protocol.

Explanation of symbols

  1, 16, 21, 24, 26 ··· MUA, 2, 3, 14, 15, 22, 23, 25 ··· MTA, 4, 12, ··· Transmission box (transmission BOX), 5, 13, ··· Inbox ( (Receiving BOX), 6, 11, 31, 32 .. Wireless device,

Claims (2)

In a message communication system for communicating message data using wireless communication,
On the sender side,
A MUA that transmits message data including a destination address and other information via a wire;
When there are a plurality of stored messages, the storing means for storing the message transmitted from the MUA, the comparing means for comparing information other than the transmission destination address of each message, and the comparison result matches, The information of the destination address of the other message is added to the information of the destination address of one message, the deletion means for deleting the other message from the storage means, and the message stored in the storage means is transferred. MTA having a transfer means, receiving a message transmitted from the MUA, and transferring the message via the wire by the transfer means;
A radio that wirelessly transmits the message transferred from the MTA,
On the receiving side,
A radio for receiving the wirelessly transmitted message;
Storage means for storing a message received by the wireless device, and when the stored message has a plurality of transmission destination addresses, the storage means copies the message by the number of the transmission destination addresses. And MTA for storing the message received by the wireless device,
A MUA that obtains the stored message from the MTA;
A message communication system. In a message communication method for communicating message data using wireless communication,
On the sending side,
MUA sends message data consisting of the destination address and other information via wire,
MTA storage means stores the message transmitted from the MUA,
When the MTA comparison means has a plurality of the stored messages, it compares information other than the destination address of each message,
When the MTA deletion means matches the comparison result, it adds the destination address information of the other message to the destination address information of one message, deletes the other message from the storage means,
The MTA transfer means transfers the message stored in the storage means via a wire,
The wireless device wirelessly transmits the message transferred from the MTA,
On the receiving side,
The wireless device receives the wirelessly transmitted message,
MTA storage means stores the message received by the radio,
The MTA duplicating means, when the accumulated message has a plurality of destination addresses, duplicates the message by the number of the destination addresses and causes the accumulating means to accumulate,
A MUA obtains the accumulated message from the MTA;
A message communication method characterized by the above.

Images