JPH06252945A - Message transfer system - Google Patents

Abstract

PURPOSE:To provide a message transfer system which can extremely reduce the inquiring time to the transfer information storing part of a directory service device and also can scatter the processing load of an MTA(message transfer agent) with higher efficiency so as to give no influence to the communications processing of a network. CONSTITUTION:An MTA 7 includes an input queue part 1 which stores temporarily the messages receives from a UA(user agent), an address deciding part 2 which decides the addresses of messages, an MTA name acquiring part 3, a message transfer part 4, a pending queue part 5 which stores temporarily the messages that could not be transferred due to the faults, etc., and a mailbox part 6 which stores the received messages. Then the MTA 7 is connected to a network 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a user agent that sends and retrieves a message, a message transfer agent that has a mailbox that stores the message and that transfers the message, and a message transfer agent. The present invention relates to a message transfer system having a directory service device having information designating a transfer destination of a message and performing transfer processing of a message sent from a user agent.

[0002]

2. Description of the Related Art Conventionally, in a message transfer system, a message sent from a user agent (hereinafter referred to as "UA") is received by a message transfer agent (hereinafter referred to as "MTA") near the UA. Then, the MTA that has received the message stores it in the input queue that temporarily stores the message.
Next, the message stored in this input queue is extracted, and the directory service device is inquired of the transfer destination of the message based on the destination of the message. Then, based on the result of the inquiry to the directory service device, (1) if the message transfer destination has a mailbox in the MTA, the message is copied to the destination mailbox of the message.

(2) When the message transfer destination has a mailbox in an MTA different from the MTA, the transfer queue transfers the message to the MTA having the destination mailbox.

(3) The message destination is "distribution list"
If so, the directory service device is again inquired, and the distribution list is expanded in order to obtain a plurality of transfer destinations belonging to the distribution list. Then, according to the acquired plurality of transfer destinations, if the transfer destination has a mailbox in the MTA, copy it to the transfer destination mailbox, and if the transfer destination has a mailbox in another MTA, MT that has a forwarding mailbox
The transfer queue transfers the message to A.

As described above, the message transmitted from the UA is received by the MTA near the UA, and the MTA inquires the directory service device about the transfer destination of the message based on the destination of the message. The message sent from the UA is transferred to the transfer destination of the message by performing the processes (1) to (3) described above according to the inquiry result.

If the message cannot be transferred due to a network failure or the like, the message is once delivered to the pending queue for storing the message, and after a predetermined time has passed, the pending queue sends the message to the transfer queue. , Forward the message again.

The "distribution list" is to send a message having the same content to a plurality of predefined destinations. Depending on the distribution list, the plurality of destinations may be multi-layered.

[0008] By the way, in Japanese Patent Laid-Open No. 195749/1990, when a sender instructs a plurality of recipients to send mail of the same content, an area for managing the number of destinations is provided to allow a plurality of recipients. By operating the system by associating one mail text file with the terminal,
Even if a large number of broadcast mails are sent, it is not necessary to create a mail text file with the same contents under each recipient's terminal, and the broadcast mail management device of the mail system that can use the file efficiently Have been described.

However, in the above-mentioned management device, although the mail text file is used efficiently, the mailboxes of a plurality of recipient terminals, which are also destinations, are searched for one by one and instructed.

[0010]

As described above, the UA
Messages sent from the MTA near the UA
To receive. And the message destination is "distribution list"
In this case, the MTA that has received the message inquires the directory service device of the transfer destination based on the destination of the message in order to find a plurality of transfer destinations belonging to this distribution list. Therefore, when there are many transfer destinations belonging to the distribution list, or when the transfer destinations belonging to the distribution list are remote locations connected to the network, it is easy to inquire the transfer destinations of the directory service device. However, it is very time-consuming, affects the communication processing between the directory service device and the MTA, and is not efficient.

As described above, the message transmitted from the UA is received by the MTA near the UA,
It is stored once in the input queue in the TA. Then, the transfer processing is performed in the order stored in the input queue. Therefore, the transfer process of the next message is not performed until the transfer process of the previously stored message is completed. Therefore, when the destination of the message is a "distribution list", it takes time to find a plurality of transfer destinations belonging to the distribution list, the transfer process of the next message is not performed, and the MTA that is performing the transfer process of the message is as if it were. However, there was a problem that the situation where the function of the was stopped occurred.

[0012] Therefore, the present invention eliminates such a problem, significantly reduces the time of inquiry to the directory service device in the MTA that receives the message, and more efficiently distributes the processing load of the MTA. , A message transfer system that does not affect the communication processing of the network.

[0013]

SUMMARY OF THE INVENTION The present invention is directed to a user agent for sending and retrieving a message, a message transfer agent having a mailbox for storing the message and for transferring the message, and the message transfer. In a message transfer system having a directory service device having information designating a message transfer destination in an agent and performing a transfer process of a message sent from a user agent, the directory service device receives the message transfer agent. A message from the message transfer agent to another message transfer agent,
The message transfer agent further comprises storage means for storing transfer information for the sub-distribution list instructed to be expanded by another transferred message transfer agent, and the message transfer agent determines whether the destination of the received message is the sub-distribution list. Determining means for determining whether or not the transfer information for the secondary distribution list is acquired from the storage means when the determination means determines that the transfer information is a secondary distribution list, and the transfer information acquired by the acquiring means. And a transfer means for transferring to another message transfer agent designated in advance based on the above.

[0014]

According to the present invention, when the message sent from the UA is the sub-distribution list, the MTA receiving the message does not expand the sub-distribution list to acquire a plurality of transfer destinations belonging to the sub-distribution list. Transfer information for the sub-distribution list is acquired from the directory service device based on the message destination. Then, another MTA that is the transfer information acquired from the directory service device in the transfer unit.
Forward the message to. Then, the other MTA to which the message has been transferred expands the sub distribution list to obtain a plurality of transfer destinations belonging to the sub distribution list by the directory service device in the same manner as the distribution list, and according to the acquired plurality of transfer destinations. , If the transfer destination has a mailbox in the MTA, copy it to the transfer destination mailbox, and if the transfer destination has a mailbox in another MTA, have the transfer destination mailbox. M
The transfer unit transfers the message to the TA.

As described above, the directory service device is provided with the transfer information for the sub-distribution list, and the MTA that receives the message from the UA does not expand the sub-distribution list and acquires the transfer information for the sub-distribution list from the directory service device. And other MT that is the acquired transfer information.
A message is transferred to A, another MTA to which the message is transferred expands the secondary distribution list, and the message is transferred to the mailbox. It is possible to significantly reduce the time required for communication, to more efficiently distribute the processing load of the MTA, and to prevent the communication processing of the network from being affected.

..

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a message transfer system which is an embodiment of the present invention.

In FIG. 1, an MTA (message transfer agent) 7 has an input queue unit 1 for temporarily storing a message transmitted from a UA (user agent),
Address determination unit 2 that determines the destination of the message, MT that acquires the other MTA name that is the transfer information from the directory service device when the destination of the message is the "sub-distribution list"
The A acquisition unit 3, the transfer unit 4 for transferring the message to another MTA, the pending queue unit 5 for temporarily storing the message when the message cannot be transferred due to a network failure, and the received message are stored. The mailbox unit 6 is included, and the MTA 7 is connected to the network 8.

Further, the directory service device 9 includes
A transfer information storage unit 10 that stores transfer information for a message destination is included, and the directory service device 9
Are connected to the network 8.

Although not shown, a plurality of UAs, MTAs, and directory service devices are connected to the network 8.

Next, the operation of the MTA in the message transfer system according to the embodiment of the present invention will be described with reference to the flowchart.

FIG. 2 is a flow chart showing the operation of the MTA in the message transfer system according to the embodiment of the present invention.

For convenience of explanation, it is assumed that a message is sent from the UA in advance, the MTA near the UA receives the message, and stores it in the input queue unit 1.

In FIG. 2, the destination discriminating unit 2 extracts the first message from the messages temporarily stored in the input queue unit 1 (step 100), and then step 1
The destination of the message fetched at 00 is read (step 101), and based on the read destination, the transfer information storage unit 10 of the directory service apparatus 9 is inquired about the transfer destination of the message (step 102). Then, in step 103, determination is made according to the transfer destination of the message inquired of the transfer information storage unit 10.

As a result of the inquiry, if the message transfer destination has the mailbox in the same MTA as the sender of the message, the process proceeds to step 104. If the message transfer destination has the mailbox in the MTA different from the sender of the message, the process proceeds to step 105. If the destination of the message is the “distribution list”, the process proceeds to step 107. Then, when the destination of the message is the “secondary distribution list”, the process proceeds to step 112.

In step 104, since the message transfer destination has a mailbox in the same MTA as the sender of the message, the message sent from the UA is copied to the transfer destination mailbox.

In step 105, since the message transfer destination has the mailbox in the MTA different from the sender of the message, the message is delivered to the transfer unit 4. Then, the transfer unit 4 transfers the message to the MTA having the mailbox as the transfer destination of the message (step 106).

In step 107, since the destination of the message is the "distribution list", the transfer information storage unit 10 is again inquired based on the destination of the message, and the transfer list of the distribution list is acquired in order to obtain a plurality of transfer destinations belonging to the distribution list. Development is performed (step 107). Then, the determination is made based on the plurality of expanded transfer destinations (step 108). If the expanded forwarding destination has a mailbox in the same MTA as the sender of the message, copy the message sent from the UA to the forwarding mailbox (step 1
09). On the other hand, when the expanded transfer destination has the mailbox in the MTA different from the sender of the message, the message is delivered to the transfer unit 4 (step 110), and the transfer unit 4 has the mailbox as the transfer destination of the message. Transfer message to MTA (step 11)
1).

In step 112, since the message destination is the "sub-distribution list", the transfer information storage unit 10 is again inquired based on the message destination to obtain another MTA name which is the transfer information of the sub-distribution list. (Step 112). Then, the message is delivered to the transfer unit 4 (step 113), and the transfer unit 4 transfers the message to the MTA corresponding to another MTA name which is the acquired transfer information (step 114).

Although not shown, in the MTA to which the message of the sub-distribution list has been transferred according to the transfer information, the MTA transfers the message again based on the destination of the message of the sub-distribution list as in the distribution list expansion processing. The information storage unit is queried, the sub-distribution list is expanded to obtain a plurality of transfer destinations belonging to the sub-distribution list, and when the expanded transfer destination has a mailbox in the MTA, a message is sent to the mailbox. The transfer destination stored and expanded is the MT
If you have a mailbox in an MTA different from A,
The message is delivered to the transfer unit, and in the transfer unit, the message is transferred to the MTA having the mailbox to which the message is transferred. Thus, when the message sent from the UA is the secondary distribution list, the UA that received the message. The MTA near the server does not expand the sub-distribution list, acquires transfer information for the sub-distribution list from the transfer information storage unit 10 of the directory service device 9 based on the destination of the message, and other transfer information is acquired according to the acquired transfer information. M
Transfer message to TA.

Then, in the MTA to which the message of the secondary distribution list has been transferred according to the acquired transfer information,
Like the distribution list, based on the message destination, the transfer information storage unit is queried again, and the sub-distribution list is expanded to obtain multiple transfer destinations belonging to the sub-distribution list.
You are forwarding the message to the destination mailbox.

Next, the storage configuration of the transfer information storage unit 10 of the directory service device 9 in the message transfer system according to the embodiment of the present invention will be described.

FIG. 3 is a diagram showing an example of a storage configuration of the transfer information storage unit 10 of the directory service device 9 in the message transfer system according to the embodiment of the present invention.

In FIG. 3, the transfer information storage unit 10 includes
The recipient, this recipient type, the mailbox address,
Distribution list, multiple destinations belonging to sub-distribution list, MTA
The address and is stored.

The destination type is "user",
There are three types: "distribution list" and "sub-distribution list".

For example, in the case of the destination "A", it is stored as the transfer information that the type of the destination is "user" and the address of the mailbox is "mb1".

In the case of the destination "L", it is stored as the transfer information that the type of the destination is "distribution list" and the plurality of destinations belonging to the distribution list are "A, B, C". There is.

In the case of the destination "S", as the transfer information, the type of the destination is "sub-distribution list", and the plurality of destinations belonging to the sub-distribution list are "D, E, F, G" and MT.
It is stored that the address of A is "mt3".

Here, an example of the method of expanding the "distribution list" will be described using the destination "L".

The transfer information storage unit of the directory service device inquires about the transfer information for the destination "L" of the message from the MTA that received the message. As a result of the inquiry, the destination "L" is "distribution list".
Then, the plurality of destinations belonging to this distribution list are "A, B,
It can be seen that it is "C". Therefore, the distribution list is expanded in order to obtain the addresses of the mailboxes of the plurality of destinations "A, B, C" belonging to this distribution list.

First, the transfer information storage unit is queried for "A", which is one of the plurality of destinations belonging to this distribution list, and the mailbox address "mb1" is acquired. "B" which is one of the destinations is inquired to the transfer information storage unit, the address "mb2" of the mailbox is acquired, and "C" which is one of the plurality of destinations belonging to the distribution list is stored in the transfer information storage unit Inquiry, the mailbox address "mb3" has been acquired.

As described above, the destination type is "distribution list".
In this case, the MTA that has received the message needs to recursively make an inquiry to the transfer information storage unit of the directory service device to obtain the addresses of the respective mailboxes of the plurality of destinations belonging to the distribution list.

On the other hand, in the case of the "sub-distribution list", for example, the sub-distribution list of the destination "S", the plurality of destinations belonging to the sub-distribution list are "D, E, F, G", and MT
It can be seen that the address of A is "mt3". Therefore, the MTA that has received the message does not expand this sub-distribution list and sends this message to the MTA "mt3".
MTA "m
"t3" expands the sub-distribution list in the same manner as the distribution list, thereby significantly reducing the inquiry time of the transfer information storage unit of the directory service device in the MTA that receives the message sent from the UA. More efficiently, the processing load of the MTA can be distributed, and the communication processing of the network is not affected.

[0044]

As described above, according to the present invention, the time required for an inquiry from the MTA that receives a message sent from the UA to the directory service device is greatly reduced, and the processing load of the MTA is more efficient. Is distributed and does not affect the communication processing of the network.

[Brief description of drawings]

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

FIG. 2 is a flowchart showing the operation of the MTA that is an embodiment of the present invention.

FIG. 3 is a storage configuration diagram of a transfer information storage unit of a directory service device that is an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Input queue part 2 Destination discrimination part 3 MTA acquisition part 4 Transfer part 5 Painting queue part 6 Mailbox part 7 MTA 8 Network 9 Directory service device 10 Transfer information storage part

Claims (1)

[Claims] 1. A user agent that sends and retrieves a message, a message transfer agent that has a mailbox that stores the message and that performs a message transfer process, and a message transfer destination in the message transfer agent. In the message transfer system for transferring a message sent from a user agent, the directory service device having a message received by the message transfer agent. From the message transfer agent to another message transfer agent, the transfer information for the sub-distribution list instructed by the transferred other message transfer agent to be expanded is stored. The agent determines the destination of the received message whether or not the destination is the secondary distribution list, and when the determination unit determines that the destination is the secondary distribution list, the agent transfers the message to the secondary distribution list. A message transfer system comprising: an acquisition unit for acquiring information; and a transfer unit for transferring to another message transfer agent designated in advance based on the transfer information acquired by the acquisition unit.