JPH1168743A - Packet communication system and packet exchange network - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packet communication system by which the load to distribute the same message from one data terminal equipment DTE to pluralities of DTEs is relieved and traffic is distributed. SOLUTION: A communication module 21 sets a logic path upon the receipt of a call from, e.g. a real DTE 11 and then stores a received message to a distribution queue. Every time a current time is informed from a time management module 20 at an interval of one minute, the module 21 discriminates whether or not the distribution time comes and sets a logic path to all real DTEs being destinations and distributes the message when the distribution time comes around and the message is stored in the distribution queue.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a packet communication system using a virtual data terminal equipment (DTE) and a packet switching network.

[0002]

2. Description of the Related Art Heretofore, this type of packet communication system has been used to match a difference in protocol between a plurality of packet-type real terminals connected to a network.
A conventional packet communication system using virtual DTE is described in, for example, Japanese Patent Application Laid-Open No. 5-183577. The packet communication system based on the virtual DTE described in this publication,
As shown in FIG. 7, a virtual DTE 30 corresponding to the real DTE 10 in a one-to-one correspondence is provided in the network 8.
Between real DTE 10 and virtual DET 30 and real DTE 11
The protocol differences between the network 8 and the virtual DTE 31 to summarize the protocol differences.
Between the virtual DTE 30 and the virtual DTE 31 in the
The minimization of a change between actual DTEs actually communicating with each other is realized.

[0003]

However, the above-mentioned conventional packet communication system using virtual DTE has the following problems. The first problem is that one DT
In the case where E transmits the same message to a plurality of DTEs, it is necessary to connect as many logical paths as the number of DTEs to be transmitted and transmit the same. The reason is that the network connects logical paths set up between DTEs and DTEs on a one-to-one basis, so when the same message is delivered to multiple DTEs,
This is because it is necessary to set logical paths for the number of distribution source DTEs and to transmit a message through each logical path.

[0004] The second problem is that the network transmits data without holding the DTE-DTE communication without suspending it, except in an unusual state such as congestion, that is, when a message (DT packet) from the DTE is received. Since the message is transmitted to the DTE of the communication partner in real time, the transmission timing of the message cannot be controlled on the network side. Therefore, if the DTE does not have a function such as a designated time message delivery method using a timer, traffic concentrates during DTE operation regardless of the real-time nature or priority of the message.

Accordingly, an object of the present invention is to provide a packet communication system and a packet switching network which can reduce the load when distributing the same message from one DTE to a plurality of DTEs and can realize traffic distribution. And

[0006]

In order to achieve this object, a packet communication system according to the present invention comprises a plurality of data terminal devices in the form of packets and a packet switching network for connecting two or more data terminal devices. A packet communication system in a packet communication system, comprising: storing a message from a data terminal device of a message delivery source in a virtual data terminal device provided in the packet switching network; When transmitting a message to a data terminal device, a logical path is set between each data terminal device, and then,
A message is delivered to each data terminal device.

[0007] According to this method, a message from a data terminal device of a message delivery source is delivered to all data terminal devices of a delivery destination by a virtual data terminal device provided in a packet switching network. The load when the distribution source data terminal device transmits the same message to a plurality of data terminal devices is reduced.

[0008] In addition, by registering the destination data terminal device in the virtual data terminal device, the message is reliably delivered to the registered data terminal device. In addition, by setting the delivery time in the virtual data terminal device, the message can be delivered from the set delivery time, so that the message can be delivered in a time zone where the traffic volume is small, and the packet switching network can be effectively utilized.

When a message is delivered to a plurality of data terminal devices to which a message is to be delivered, if there is a data terminal device that cannot deliver the message, the data terminal device is skipped and the next data terminal device is skipped. And deliver messages to them. As a result, the message can be delivered to a data terminal device other than the data terminal device having a failure such as a transmission line failure or a terminal stop, so that the failure due to the failure can be minimized.

[0010] A packet switching network according to the present invention is a packet switching network for controlling the exchange of messages between a plurality of data terminal devices, and includes a time management module for outputting the current time at fixed time intervals, and a message delivery source. A logical path is set and canceled between the data terminal device and the data terminal device to which the message is to be distributed, and when the current time reaches the distribution time, all of the stored messages from the data terminal device at the message distribution source are stored. And a communication module for transmitting the data to the data terminal device of the distribution destination.

According to this configuration, when there is a data terminal device that distributes a message, a logical path is set between itself and the data terminal device. After setting the logical path, the message transmitted from the data terminal device is stored, and when the current time reaches the distribution time, the logical path is set between all the data terminal devices at the distribution destination and stored. The delivered messages are sequentially delivered. And as soon as the distribution is over,
Release the logical path.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (I) First Embodiment FIG. 1 is a block diagram showing a configuration of a packet communication system which is a first embodiment of a packet communication system according to the present invention. In the packet communication system according to this embodiment, the real data terminal device (real DTE) sets a logical path by designating a virtual data terminal device (virtual DTE) that meets its own distribution conditions. Once the message is stored and the delivery time comes, a message is delivered after setting the logical path to all the real DTEs registered as the delivery destination.

In the packet switching network 9, a time management module 20 and a communication module 21 are provided. The time management module 20 manages the time, and notifies the communication module 21 of the time every minute. The communication module 21 sets and releases a logical path to and from the real DTE, and stores and distributes a message. The distribution starts when the current time reaches a preset distribution time.

At least one virtual DTE can be registered in the communication module 21, and a distribution time and distribution information of a distribution destination DTE can be set in the virtual DTE. In this figure, virtual DTEs 30 and 31 are registered. In the virtual DTE 30, the distribution destination: the real DTE 12, 1
3, 14, and distribution time: 02:00 are set. In the virtual DTE 31, distribution information including a distribution destination: real DTEs 14 and 15 and a distribution time: 04:30 is set. Further, a delivery queue is provided in the virtual DTE, and temporarily stores a message to be transmitted.

The communication module 21 checks whether or not a virtual DTE having the current time as the distribution time is registered each time the time is notified from the time management module 20 and determines that there is any registered virtual DTE. It is determined whether or not a message is stored in the delivery queue, and if the message is stored, it is delivered. At the time of message delivery, a logical path is set between the delivery source virtual DTE and the delivery destination real DTE. After the delivery of the message, the logical path between the delivery source virtual DTE and the delivery destination real DTE is released.

Next, the operation of the packet communication system having the above configuration will be described with reference to the flowcharts of FIGS. (A) Message Storage Phase When the real DTE 11 uses a delivery service registered in the virtual DTE 31, the real DTE 11
(Step A1). After setting the logical path, the real DTE 11 transmits a message to the virtual DTE 31 using the logical path. Upon receiving the message transmitted from the real DTE 11, the virtual DTE 31 stores the message in a delivery queue (step A2).
After storing the message, the real DTE 11 is prompted to release the logical path (step A3).

(B) Message delivery phase Time management module 2 in packet switching network 9
0 notifies the communication module 21 of the current time every minute (step A4). The communication module 21 that has received the time notification from the time management module 20 examines whether there is a virtual DTE whose current time is registered as the distribution time (step A5). In this close examination, if the current time is 04:30, it matches the delivery time of the message of the virtual DTE 31. Then, if the message is stored in the delivery queue of the virtual DTE 31, it is delivered.

In this case, the virtual DTE 31 sets a logical path between the distribution destination and the real DTEs 14 and 15 (step A7). After setting the logical path, the actual DTE1
The message stored in the delivery queue is transmitted using each of the logical paths 4 and 15 (step A8). Virtual D
When the message delivery to each of the real DTEs 14 and 15 ends, the TE 31 releases the logical path (Step A9).

Here, further explanation will be given with reference to the sequence diagram of FIG. When an incoming (CN) packet from the real DTE 11 arrives at the virtual DTE and the called DTE address 31 is registered in the virtual DTE, a logical path is set with the virtual DTE 31. After the logical path is set, the virtual DTE
Reference numeral 31 stores the message (DT packet) in the delivery queue every time a message (DT packet) is received from the real DTE 11. At this time, the virtual DT
E31 determines the end of one message by the more pit (continuous display) on the DT packet, and ends the message when the DT packet with the more pit of "0" (no continuation) is received. At this time, the virtual DTE 31 is
A DT packet in which a qualify bit indicating a DT packet that is not user data is set to “1” is transmitted to prompt release of a logical path from the actual DT 11.

As described above, in the first embodiment, the communication module 21 sets a logical path by an incoming call from the real DTE, and then stores the received message in the delivery queue. Then, from the time management module 20 to 1
Every time the current time is notified at minute intervals, it is determined whether the current time is the distribution time. If the current time is the distribution time and the message is stored in the distribution queue, all the real DTEs of the distribution destination are determined.
, A logical path is set, and the message is delivered.

Therefore, it is possible to reduce the burden on the real DTEs that intend to deliver messages to a plurality of real DTEs, and to deliver messages with a relatively low priority at night when traffic is relatively low. Further, since the virtual DTE can be realized in the form of software in the packet switching network 9, the present invention can be easily applied to an existing packet switching network.

(II) Second Embodiment FIG. 5 is a block diagram showing a configuration of a packet communication system according to a second embodiment of the packet communication system of the present invention. In this figure, a virtual DTE 30 is registered in the packet switching network 16 and this virtual DTE 30 is registered.
In the field 30, the real DTE 11 is set as the first destination, the real DTE 12 is set as the second destination, and the distribution information of 04:30 is set as the distribution time.

As shown in the sequence diagram of FIG.
When the TE 30 attempts to deliver the stored message at 04:30, which is the delivery time, the real DTE 11 that is the first delivery destination for some reason, such as a transmission line failure or a terminal being stopped.
If the distribution to the real DTE 12 is not possible, the distribution to the real DTE 11 is stopped and the real DTE 12 registered as the second distribution destination is stopped.
Delivery to As described above, in the second embodiment, if there is a data terminal device that cannot deliver a message, the data terminal device is skipped and the message is delivered to the next data terminal device. As a result, the message can be delivered to a data terminal device other than the data terminal device having a failure such as a transmission line failure or a terminal stop, so that the failure due to the failure can be minimized.

[0024]

According to the present invention, the DTE of one distribution source
When transmitting the same message to a plurality of DTEs of the distribution destinations, the same number of logical paths as the number of the DTEs of the distribution destinations are set, and the same message is transmitted to each logical path. The burden at the time of distribution of the distribution source DTE can be greatly reduced. In addition, when one DTE transmits a message to a plurality of DTEs fixedly and regularly, it is only necessary to register the distribution condition as a virtual DTE, so that the effective use of the communication path between the distribution source DTE and the network is possible. Becomes possible.

Also, since the delivery time can be set for each virtual DTE, a time zone with a small amount of traffic is set as the delivery time in the virtual DTE for delivering a message of which real time is not required, so that the traffic time can be set. It is possible to sort from a time zone with a lot of time to a time zone with a little time, and the network can be used effectively.

If there is a DTE for which message delivery is impossible, the DTE is skipped and the message is delivered to the next DTE. Since the message can be reliably delivered to the DTE, failures due to malfunctions can be minimized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of a packet communication system according to the present invention.

FIG. 2 is a flowchart illustrating an operation of the first embodiment.

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

FIG. 4 is a sequence diagram showing an operation of the first embodiment.

FIG. 5 is a block diagram showing a configuration of a second embodiment of the packet communication system according to the present invention.

FIG. 6 is a sequence diagram illustrating an operation according to the second embodiment.

FIG. 7 is a diagram for explaining a conventional packet communication system.

[Explanation of symbols]

 9, 16 packet switching network 10, 11, 12, 13, 14, 15 data terminal device 20 time management module 21, 22 communication module 30, 31 virtual data terminal device

Claims (6)

[Claims] 1. A packet communication system in a packet communication system comprising a plurality of packet-type data terminal devices and a packet-switched network for connecting between two or more data terminal devices, comprising: When a message from a terminal device is stored in a virtual data terminal device provided in the packet switching network, and when a message is transmitted from the virtual data terminal device to all data terminal devices to be distributed, each data terminal device Set a logical path between
Thereafter, a packet communication method characterized by delivering a message to each data terminal device. 2. The data terminal device according to claim 1, wherein at least one data terminal device to which the message is to be delivered is registered in the virtual data terminal device, and the message is delivered to all the registered data terminal devices. Packet communication method. 3. The distribution time is set in the virtual data terminal device, and the message is distributed from the point in time when the current time reaches the set distribution time.
The packet communication method according to any one of the above. 4. When delivering a message to a plurality of data terminal devices to which a message is to be delivered, if there is a data terminal device that cannot deliver the message, the data terminal device is skipped and the next data terminal device is skipped. 4. The packet communication method according to claim 1, wherein a message is delivered to the packet communication system. 5. A packet switching network for controlling exchange of messages between a plurality of data terminal devices, comprising: a time management module for outputting a current time at regular time intervals; a data terminal device as a message delivery source; A logical path is set and released with each of the destination data terminal devices, and when the current time reaches the distribution time, the accumulated messages from the message source data terminal device are transferred to all the destination data terminals. A packet switching network, comprising: a communication module that transmits to a device. 6. When distributing a message to a plurality of data distribution destination data terminal devices, the communication module skips any data terminal device that cannot distribute the message and skips the next data terminal device. 6. The packet switching network according to claim 5, wherein a message is delivered to said data terminal device.