JPH11150556A - Gateway for mail and method for gateway service for mail - Google Patents

Abstract

PROBLEM TO BE SOLVED: To communicate an electronic mail between an ISDN channel and the internet even when the user of the ISDN channel acquires no mail address for the internet. SOLUTION: The gateway 40 connects with an ISDN channel 30 and the internet 60 to relay data between the ISDN channel 30 and the internet 60 is provided with a protocol control means that controls a communication protocol of the ISDN channel 30 or the internet 60. The protocol control means consists of two means, one of which converts the protocol of the mail information upon receipt of mail information from the ISDN channel 30 and discriminates a mail address in the mail information as a destination, and sends the information to the internet 60. The other means converts the protocol of the mail information upon receipt of the mail information from the Internet 60, discriminates a telephone number in the mail information as a destination and sends the information to the ISDN channel 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit for converting a protocol in sending and receiving a mail message, and more particularly, to a control of sending and receiving mail of a gateway which performs a relay operation between an ISDN line and a mail server in the Internet.

[0002]

2. Description of the Related Art Conventionally, as a general electronic mail exchange, there is a mail delivery protocol based on a TCP / IP protocol used on the Internet. The protocol for delivery of this mail is
Internet standard SMTP (Simple Mai)
l Transfer Protocol (abbreviation of simple mail transfer protocol) is most commonly used, and a destination is specified by using a mail address in a domain format, and mail is transmitted and received.

As a method for exchanging data between the ISDN and the LAN, for example, Japanese Patent Application Laid-Open No.
No. 45 discloses this. According to this method, a communication device corresponding to a relay device receives data transmitted via ISDN, converts an incoming subaddress of ISDN into an e-mail address of a communication terminal connected to the LAN according to an address correspondence table, and transmits the data to a destination. Send.

[0004]

However, in the above-mentioned standard method, mail transmission and reception can be used only by a user who has acquired an Internet mail address. However, there is a problem that even if a user who does not use the ISDN terminal can send and receive mail between the Internet.

In the method disclosed in Japanese Patent Laid-Open No. 6-164645, the relay device must prepare an address correspondence table corresponding to the destination address for each destination subaddress. For this, it is necessary to investigate the address of the transmission destination at the time of constructing the system, and to set the relationship corresponding to the address of the point-to-point communication destination and the sub-address.
For this reason, the system construction takes a lot of man-hours, the sending side needs to know the correspondence, the problem that a larger system requires a larger amount of data, Further, the terminal connected to the LAN side does not know the existence of the subaddress, so the ISDN
There was a problem that it was not possible to send to the terminal connected to.

[0006] An object of the present invention is to provide an ISDN even if the user does not have an Internet mail address.
It is possible to send from a network to a mail server connected to the Internet, and to send an e-mail received from any mail server on the Internet to a destination user who has not obtained a mail address via the ISDN network. is there.

[0007]

In order to achieve the above object, a mail gateway according to the present invention is connected to an ISDN line and the Internet, and relays data between the ISDN line and the Internet. A protocol control means for controlling a communication protocol of the ISDN line or the Internet, wherein the protocol control means converts a protocol of the first mail information when the first mail information is received from the ISDN line. First transmission means for determining a mail address in the first mail information as a destination and transmitting the mail information to the Internet; and when receiving the second mail information from the Internet, converting the second mail information into a protocol. Then, the telephone number in the second mail information is determined as the destination, and the IS It is characterized by a second transmission means for transmitting the N line.

[0008] Further, the first mail information is data set in a field in a call setting message, and the first mail information is received by the call setting message.

Further, in the second transmitting means, the second transmitting means
Is set in the user / user information field on the call setup message and transmitted to the ISDN line.

Further, the second transmitting means sets the telephone number as a destination in a called number field on a call setting message.

Further, the first mail information is characterized by including a telephone number of a caller, a telephone number of the gateway, a mail address of a transmission destination, and a mail text.

Further, the mail gateway service method according to the present invention provides a gateway connected to an ISDN line and the Internet for relaying data between the ISDN line and the Internet, and connecting to the ISDN line and the first device. And an ISDN terminal adapter for relaying data between the ISDN line and the first device, wherein when mail information is transmitted from the first device to a second device connected to the Internet, ISD
When the mail information is received at the N terminal adapter, the mail information is set in the user / user information field of the call setting message, and the call setting message is transmitted to the telephone number of the gateway via the ISDN line. And the gateway receiving the call setup message transmitted in the first step converts the user / user information on the call setup message into a protocol of the Internet e-mail and converts the user / user information in the user / user information. And a second step of identifying a destination from the e-mail address set in the field and transmitting the destination to the Internet.

Further, the mail gateway service method of the present invention includes a gateway connected to an ISDN line and the Internet and relaying data between the ISDN line and the Internet.
When mail information according to the Internet e-mail protocol is received from the Internet, the mail information is converted into a protocol used on an ISDN line, and the mail information is set in a user / user information field of a call setup message. The destination telephone number is set in the called number field of the call setup message, and the ISDN
It is characterized by transmitting to a line.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the operation will be described below.

The ISDN service includes transmitting and receiving users.
Network interface (UNI: User-Network)
There is a bearer (transmission) service (first layer to third layer) defined between the interfaces. In the third layer (corresponding to the network layer of the OSI reference model), Q.2 of the ITU-T Recommendation User / user information (UUI: User User Information) in a SETUP message which is a call setup message specified in 931
The mail information is put in a field of 128 bytes or less (abbreviation of the communication) (hereinafter, a communication method using this method is abbreviated as UUI mail).

The UUI mail gateway connected to the ISDN line receives the UUI mail from the ISDN line side, converts the received mail information into an SMTP protocol, and sends it to the SMTP server side (mail server) via the Internet. . Furthermore, the mail information received from the SMTP server is protocol-converted into UUI mail,
Transmit to ISDN line. As a result, even if the operator having the ISDN terminal adapter does not have a mail address, if the telephone number of the UUI mail gateway and the mail address of the mail transmission destination are known, mail can be sent to any mail server. Can be.
In addition, an operator from the Internet can send an e-mail to an e-mail recipient who has not obtained an e-mail address if the mail address of the UUI mail gateway and the telephone number of the e-mail are known. The opponent becomes wider and resources can be used effectively.

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a system configuration diagram of a gateway service for UUI mail according to the present invention.

In FIG. 1, an ISDN terminal adapter 1, a personal computer 20 connected to the ISDN terminal adapter 1 and a serial cable 21, an ISDN line 3
0, UUI mail gateway 4 connected to Internet 60, ISDN line 30, and Internet 60
0, a mail server 80 operating according to the SMTP protocol connected to the Internet 60, and a personal computer 90 under the mail server 80. Although a personal computer is used as a user's device, other devices such as a communication device including a computer may be used.

FIG. 2 is an apparatus configuration diagram of the ISDN terminal adapter 1 of FIG.

In FIG. 2, an ISDN terminal adapter 1 includes a call control circuit 10 for controlling a communication protocol of an ISDN line, and an ISDN interface control circuit 1 connected to an ISDN line 30 for realizing message and data transfer.
4. Personal computer interface control circuit 1 for transmitting / receiving data to / from personal computer 20 via serial cable 21
2. The mail editing control circuit 13 analyzes the received data to convert it into a mail message, and registers the mail information received from the UUI mail gateway 40 in the memory 11, and holds the mail information from the UUI mail gateway. A memory 11 is provided.

FIG. 3 is a block diagram of the UUI mail gateway of the present invention shown in FIG.

In FIG. 3, the UUI mail gateway 40 includes a call control circuit 50 for controlling a communication protocol of the ISDN line, an ISDN interface control circuit 52 for connecting to the ISDN line 30 and realizing message and data transfer, and an ISDN line 30. A protocol conversion control circuit 54 that analyzes the mail information received via the network, converts the mail information into the SMTP protocol, and stores the converted mail information in the memory 51;
The mail information stored in the memory 51 is transferred to the Internet 6
Dedicated line interface control circuit 53 for transferring to 0
It has.

In FIG. 2, a call control circuit 10 includes a memory 11, a personal computer interface control circuit 12, an ISDN
Interface control circuit 14, mail editing control circuit 13
And controls the communication protocol for the ISDN line 30 via the ISDN interface control circuit 14. The personal computer interface control circuit 12 has a function of receiving data from the personal computer 20 connected via the serial cable 21 and notifying the data to the mail editing control circuit 13 via the call control circuit 10. ISD
The N interface control circuit 14 controls an interface with the ISDN line 30, establishes line synchronization and link establishment, and controls transmission and reception of messages. The mail editing control circuit 13 is connected to the call control circuit 10, analyzes data received from the personal computer 20 through the personal computer interface control circuit 12, and analyzes the user / user information in the call setting message.
Put the mail information in the user information field and ISD
It passes to the N interface control circuit 14. Further, the mail editing control circuit 13 includes the ISDN interface control circuit 1
4 stores the mail information received from the UUI mail gateway through the memory 11. The memory 11 is connected to the call control circuit 10 and is a memory in which the mail editing control circuit 13 records mail information.

In FIG. 3, a call control circuit 50 includes a memory 51, an ISDN interface control circuit 52, a dedicated line interface control circuit 53, and a protocol conversion control circuit 5.
4 and controls the communication protocol of the ISDN line 30 via the ISDN interface control circuit 52. I
The SDN interface control circuit 52 is connected to the ISDN line 3
0 to control the synchronization of the line, the establishment of the link, and the transmission and reception of messages. The protocol conversion control circuit 54 is connected to the call control circuit 50,
It has a function of converting mail information received from the ISDN line via the DN interface control circuit 52 into the SMTP protocol, storing the converted mail information in the memory 51, and notifying the dedicated line interface control circuit 53.
The dedicated line interface control circuit 53 includes a call control circuit 50
And has a function of reading mail information notified from the protocol conversion control circuit 54 from the memory 51 and transmitting the information to the mail server 80 via the Internet 60. The memory 51 is connected to the call control circuit 50,
The protocol editing control circuit 54 is a memory for recording mail information via the call control circuit 50.

Next, an embodiment of the present invention will be described with reference to FIG.

When the personal computer 20 on the transmitting side adds mail information and transmits it to the UUI mail gateway 40,
The ISDN terminal adapter 1 receives the mail information from the personal computer 20, edits it into UUI mail, and transmits it to the ISDN line 30.

The UUI mail gateway 40 is an IS
UUI mail received from the DN line can be converted into an SMTP protocol command and transmitted to the SMTP server 80 via the Internet 60, and mail can be transmitted to any mail server via the Internet. Also, a mail server 80 in the Internet 60
The UUI mail gateway 40 receives the mail information arriving from the UUI mail, converts it into UUI mail, and
The e-mail can be transmitted to the terminal adapter 1, and the e-mail can be transmitted to the receiving user who has not acquired the e-mail address from the Internet.

Next, the operation of the embodiment of the present invention will be described with reference to FIGS. 1, 2, 3 and 4.

First, an operation for transmitting an electronic mail from the personal computer 20 on the ISDN side to the personal computer 90 connected to the Internet 60 will be described.

When sending electronic mail from the sending personal computer 20, mail information 70 is sent to the telephone number of the UUI mail gateway 40. This mail information 7
0 contains the telephone number of the caller, the telephone number of the UUI mail gateway 40, the mail address (address or IP address shown in domain format) of the transmission destination, and the mail text.

The mail information 70 transmitted from the personal computer 20 is received by the personal computer interface control circuit 12 in the transmitting ISDN terminal 1 via the serial cable 21 connected to the ISDN terminal adapter 1. The mail editing control circuit 13 converts the mail information 7 into a UUI mail based on the mail information received from the personal computer.
0 is set in the user / user information field of the call setup message (hereinafter referred to as SETUP), and the call control circuit 1
0 transmits the SETUP 71 to the ISDN line 30 through the ISDN interface control circuit 14.

IS in UUI mail gateway 40
ISDN line 3 by the DN line interface control circuit 52
The SETUP 71 from 0 is received, and user / user information in the SETUP 71 is stored in the memory 51.
The protocol conversion control circuit 54 converts mail information in the user information stored in the memory 51 into an SMTP protocol command. In this case, the mail information includes the telephone number of the sender, the mail address (address in domain format or IP address) of the sender, and the mail text. The protocol conversion control circuit 54
Determines an IP address as a destination address according to a conversion table in the memory 51 in order to send mail information to the mail server 80 through the call control circuit 50.
Set to the destination address of the field (TCP / IP protocol). At this time, when the IP address is set as the mail address in the mail information, the IP address is set as the destination address of the IP header field without using the conversion table.

The call control circuit 50 transmits the SMTP command 72 to the Internet 60 of the mail server 80 through the dedicated line interface control circuit 53. That is,
By reaching the mail server 80, it reaches the personal computer 90 under the mail server. In this way, mail can be sent to any mail server via the Internet.

Next, an operation in the case where an electronic mail is input from the personal computer 90 (under the mail server 80) connected to the Internet 60 via the mail server 80 will be described.

SMT which is a command for the SMTP protocol arriving from the mail server 80 in the Internet
The P command 73 is received by the dedicated line interface control circuit 53 in the UUI mail gateway 40 via the Internet 60 connected to the UUI mail gateway 40. Protocol conversion control circuit 5
4 converts the SMTP command 73 into a UUI mail via the call control circuit 50 and stores it in the memory 51. In this case, the information of the UUI mail includes the address of the sender (address in domain format or IP address), the telephone number of the transmission destination, and the text of the mail. If the received SMTP command 73 is converted into UUI mail information and becomes 128 bytes or more, the UUI mail information is divided into 128 bytes or less and stored in the memory 51.

The call control circuit 50 retrieves the mail information stored in the memory 51, and retrieves the user information in the SETUP.
It is set in the user information field, and SE is set for an arbitrary telephone number through the ISDN interface control circuit 52.
The TUP 74 is transmitted to the ISDN line 30. Since the telephone number of the destination is directly set in the field of the called number in SETUP 74 at this time, it is sent to the ISDN terminal adapter 1 of the destination. If there is UUI mail information divided and stored because the data exceeds 128 bytes under the control of the protocol conversion circuit 54, the ISD
The SETUP 74 will transmit the number divided into the N lines 30.

The ISDN terminal adapter 1 is a SET
The UP 74 is received from the ISDN line 30 via the ISDN interface control circuit 14 and stored in the memory 11. The call control circuit 10 in the ISDN terminal adapter 1 responds to a mail read request 75 from the personal computer 20.
Can retrieve the stored mail information 76 from the memory 11 and transmit the mail information 76 via the serial cable 21 through the personal computer interface control circuit 12.

In the above description, the ISDN terminal adapter 1 is often installed near the personal computer or mounted in the personal computer.

Also, SM is used as an e-mail protocol.
Although the TP has been described as an example, it is needless to say that other electronic mail protocols are included in the present invention.

As described above, an e-mail can be transmitted to a destination user whose e-mail address has not been acquired.

Further, the mail gateway of the present invention comprises:
The subaddress and I of each user connected to the ISDN line
Instead of having a correspondence table with the P address, it is only necessary to have a correspondence table between the address in the domain format of the transmission destination and the IP address (in this case, only the server-side IP address and no individual user information is required). . Also in this case, the conversion table is not required if an IP address is set in the mail information in advance. Therefore, the mail gateway does not need a huge amount of information to know in advance the address information of the transmission / reception destination of each individual user.

[0043]

As described above, the first effect of the present invention is that the operator sends a mail to an arbitrary mail server at a low price (for example, 0.4 yen at the current price). Then, the mail can be transmitted to a mail server in the Internet. The reason is that the mail information is set in the user information in the SETUP, and therefore, only 0.4 yen is charged for one SETUP.

A second effect is that a mail can be transmitted from the Internet to a destination user who has not obtained a mail address. The reason is that the UUI mail gateway can transmit mail information received from any mail server to any other party via the ISDN line.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of an embodiment of the present invention.

FIG. 2 is a device configuration diagram showing an example of an internal configuration of the device of the ISDN terminal adapter of FIG. 1;

FIG. 3 is a device configuration diagram showing an example of an internal configuration of a device of the UUI mail gateway of FIG. 1;

FIG. 4 is a sequence diagram of an ISDN terminal adapter and a UUI mail gateway showing an embodiment of the present invention.

[Explanation of symbols]

 1 ISDN Terminal Adapter 20, 90 Personal Computer 21 Serial Cable 30 ISDN Line 40 UUI Mail Gateway 60 Internet 10, 50 Call Control Circuit 11, 51 Memory 12 PC Interface Control Circuit 13 Mail Editing Control Circuit 14, 52 ISDN Interface Control Circuit 53 Dedicated Line interface control circuit 54 protocol conversion control circuit 70 mail information 71,74 SETUP 72,73 SMTP command 75 mail read request 76 mail information 80 mail server

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04M 3/00

Claims (7)

[Claims] A gateway connected to an ISDN line and the Internet for relaying data between the ISDN line and the Internet, comprising: a protocol control means for controlling a communication protocol of the ISDN line or the Internet; In the control means, when the first mail information from the ISDN line is received, a protocol conversion of the first mail information is performed, a mail address in the first mail information is determined as a destination, and the first mail information is transmitted to the Internet. (1) transmitting the second mail information from the Internet and receiving the second mail information from the Internet, converting the protocol of the second mail information, determining the telephone number in the second mail information as a destination, and connecting to the ISDN line; Mail gateway having second transmitting means for transmitting. . 2. The mail gateway according to claim 1, wherein the first mail information is data set in a field in a call setup message, and receives the call setup message. 3. The system according to claim 1, wherein said second transmitting means sets second mail information in a user / user information field on a call setup message and transmits the second mail information to said ISDN line. Mail gateway for. 4. The mail gateway according to claim 1, wherein the second transmitting means sets the telephone number as a destination in a field of a called number on a call setting message. 5. The first mail information according to claim 1, wherein the first mail information includes a telephone number of a caller, a telephone number of the gateway, a mail address of a transmission destination, and a mail text. Mail gateway. 6. A gateway connected to an ISDN line and the Internet for relaying data between the ISDN line and the Internet, a gateway connected to the ISDN line and a first device, and the ISDN line and the first device. An ISDN terminal adapter for relaying data between the first device and the second device connected to the Internet when mail information is transmitted from the first device to the second device.
When the mail information is received at the N terminal adapter, the mail information is set in the user / user information field of the call setting message, and the call setting message is transmitted to the telephone number of the gateway via the ISDN line. And the gateway receiving the call setup message transmitted in the first step converts the user / user information on the call setup message into a protocol of the Internet e-mail and converts the user / user information in the user / user information. A second step of identifying a destination from the e-mail address set in the field and transmitting the destination to the Internet. 7. A gateway connected to an ISDN line and the Internet for relaying data between the ISDN line and the Internet, wherein the gateway comprises:
When mail information according to the Internet e-mail protocol is received from the Internet, the mail information is converted into a protocol used on an ISDN line, and the mail information is set in a user / user information field of a call setup message. The destination telephone number is set in the called number field of the call setup message, and the ISDN
A mail gateway service method, wherein the mail gateway service is transmitted to a line.