JPH02309734A - Data transmission system - Google Patents

Abstract

PURPOSE:To offer various packet exchange services even to a system which is not in use by connecting both systems of terminals of dual systems to a packet network and providing logical channels respectively and sending data which indicates whether a communication is possible or not between both the systems of the terminals. CONSTITUTION:For example, when the system TA1 of a terminal 10 is put in use, the system TA1 sends data indicating that a communication is possible to both systems TA2 and TB2 of a terminal 20 covered by an exchange 20 through a local channel. Here, when the system TA2 of the terminal 20 is in use, the system TA2 sends an acknowledgment answer and the system TB2 sends a negative acknowledgment answer. The acknowledgment data of the system TA2 and the negative acknowledgment data of the system TB2 are received by the systems TA1 and TB1 of the terminal 10. Consequently, the system TA1 of the terminal 10 is enabled to have a communication with the system TA2 of the opposite terminal and terminal data are transmitted through the logical channel. At this time, a system which is not in use is connected to the packet network, so the system is offered the packet exchange services.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission system for a packet-switched network using a packet switch.

[Conventional technology]

2 through a packet switching network using a packet switch.
When transmitting data between terminals in a heavy system, a line switch is installed between the exchange and the terminals.

Then, by connecting the current terminal to the exchange,
There is a method for transmitting data between the active systems of each terminal.

[Problem to be solved by the invention]

In the conventional data transmission system described above, a line switch is controlled every time a system switchover of a terminal occurs. Therefore, disconnection/connection of the physical line occurs, resulting in a delay in data transmission time due to sequence switching.

Additionally, there is a need to change the operating mode in response to poor control of the line switching device.

Furthermore, since the system that is not currently in use is completely separated from the packet switching network, various packet switching services such as table maintenance services via the packet switching network cannot be provided to the system that is not currently in use. There are drawbacks.

SUMMARY OF THE INVENTION An object of the present invention is to provide a data transmission system that eliminates these drawbacks and allows even systems that are not currently in use to receive packet switching services.

[Means to solve the problem]

The present invention is a data transmission method in which both systems of duplex terminals are connected to a packet switch, logical channels are provided between the terminals of both systems, and data is transmitted via these logical channels, comprising: Each terminal system transmits "communication ready" data to all connected logical channels in the case of the currently used system, and to all connected logical channels in the case of the non-current system, according to the operation mode of both systems. A transmitter that sends "communication not possible" data to the logical channel, and when receiving "communication possible" data from the logical channel, responds with "communication possible" data in the case of the current system. , a response means that responds with "communication unavailable" data in the case of a system that is not currently in use; and a response means that transmits and receives "communication possible" data based on the data transmitted by the transmitting means and the response data of the response means. It is characterized by having a logical channel and a transmission means for transmitting data.

〔Example〕

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

FIG. 1 is a network configuration diagram showing an embodiment of the present invention. The data transmission method of this embodiment is based on systems TAI and TA2, which are systems A of terminals 10 and 20 that transmit data.
and the systems TBI and TB2 which are the B system of terminal 10.20,
Exchange Ps that connects each system through logical channels
i, and PS2.

In this data transmission method, each terminal
Both systems are connected to exchanges Psi and PS2.

The terminal 10 has a dual system TAI and 'r'B1, with one side serving as the active system. Similarly, the system T of the terminal 20
One side of A2 and TB2 is currently in use.

A block configuration diagram of these terminals 10 and 20 in each prefecture is shown in FIG. In FIG. 2, an operation mode determination unit 1 determines the operation mode of its own system with respect to other systems, and outputs the determined operation mode to a communication enable/disable determination unit 2. When the current mode is input, the communicable/impossible determining section 2 sends "communicable" data to the communicable output section 3. When “communication possible” is output from the communication possible output section 3 to the transmitting section 8,
This "communication possible" is output from the transmitter 8 to all logical channels via the line controller 11. Furthermore, this "communication possible" is output to all partner terminals on the network.

If the operation mode is not the current mode, the communication enable/disable determining section 2 requests "communication disable" to the communication disable output section 4. "
"Communication not possible" is output from the transmitter 8 to all logical channels, and is output via the line controller 11 to all partner terminals on the network. Furthermore, when requesting "communication possible" and "communication not possible", the communication possible/impossible determining section 2 also outputs the communication possible/impossible state to the interconnection determining section 5.

When the data from the other party's terminal, that is, the data received from the line control unit 11, is "communication enabled", the communication enabled input unit 6 that received this data from the receiving unit 9 inputs the number of the logical channel on which the data was received. The interconnection determination circuit 52 outputs the communication power section 32 to the communication failure output section 4. The communication enabled output section 31 and the communication disabled output section 4 indicate "communication enabled" or "communication disabled".
Output to the corresponding logical channel. When the interconnection determination unit 5 inputs the logical channel numbers that have become communicable with each other to the terminal data input/output unit 10, the terminal input/output data becomes communicable to the corresponding logical channel, and the data of the terminal data generation unit 12 The human output of data from the line control unit 11 is performed for each logical channel. In addition, if the data received from the receiving unit 9 is “communication unavailable”, the communication unavailable input unit 7
``Communication not possible'' causes terminal input/output data transmission to stop for the logical channel that received the ``Communication not possible'' message.

The logical channels are system TAI and TA2. System TAI and TB2
．． System TBI and TA2. Four systems, TBI and TB2, are prepared.

Next, the operation of this embodiment will be explained.

In FIG. 1, when the system TAI of, for example, the terminal 10 accommodated in the exchange PSl of the packet switching network becomes active, the system TAI is transferred to the system TAI of the terminal 20 accommodated in the exchange 820 via the logical channel.゜Send "communication possible" data to both TB2.

Here, if the system TA2 of the terminal 20 is currently in use, the system TA2 responds with "communication possible" and the system TB2 responds with "communication not possible".

The data indicating "communication possible" for system TA2 and "communication not possible" for system TB2 are received by systems TAI and TBI of terminal 10. As a result, the system TAI of the terminal 10 can communicate with the system TA2 of the other terminal, and terminal data can be transmitted through the corresponding logical channel. At this time, since the systems that are not currently in use are also connected to the packet switching network, they can receive packet switching services.

In this way, in a packet network consisting of duplexed terminals and switches, both sides of the duplexed terminals are connected to the switch, a logical channel is established between the terminals on both sides, and the operating modes of both systems are controlled. Accordingly, the active system sends "communication available" to all connected logical channels, and the non-active system sends "communication unavailable" to all connected logical channels, and "communication available". When receiving the message, the active system responds with "Communication possible", and the non-current system responds with "Communication unavailable", and when mutual terminals send and receive "Communication possible", data is sent to the corresponding logical channel. to transmit.

〔Effect of the invention〕

As explained above, the present invention connects both terminals of a duplex system to a packet network, establishes a logical channel between them, and transmits data indicating "communication possible" and "communication not possible" between both terminal systems. By doing so, the line switch used in the prior art can be removed, and physical line disconnection/connection when system switching occurs is eliminated. Furthermore, since systems that are not currently in use are also connected to the packet switching network, there is an advantage that various packet switching services can be received.

[Brief explanation of the drawing]

FIG. 1 is a network configuration diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of a terminal shown in the embodiment shown in FIG. TAI...Terminal engineer's A system TBI...Terminal 1's B system TA2...Terminal 2's A system TB2...Terminal 2's B system Psi, PS2...Packet switch agent Patent attorney Sa Iwa Yoshiyuki Figure 1 Figure 2

Claims (1)

[Claims] (1) Connect both systems of duplex terminals to a packet switch,
A data transmission method in which a logical channel is provided between the terminals of both systems, and data is transmitted via this logical channel, in which the system of each terminal is set according to the operation mode of both systems. Transmitting means that transmits "communication possible" data to all connected logical channels, and in the case of a system that is not currently in use, transmitting "communication impossible" data to all connected logical channels; A response means that, when receiving "communication possible" data from a logical channel, responds with "communication possible" data in the case of the currently used system, and responds with "communication impossible" data in the case of the non-current system. and a logical channel that transmits and receives "communication possible" data based on the data transmitted by the transmitting means and the response data of the responding means, and a transmitting means that transmits data. method.