JPH05219085A - Loop type data communication equipment - Google Patents

Abstract

PURPOSE:To obtain the loop type data communication equipment which can secure a communication path, even when a double fault is generated on a transmission line. CONSTITUTION:This equipment is constituted of a terminal equipment 40 by which a user transmits and receives data, a first data transmission device 21, a second data transmission device 22, a third data transmission device 23 and a fourth data transmission device 24 for executing transmission and reception to and from other station through different loop transmission lines, a transmission line selecting part 1 for monitoring each data transmission device and selecting the data transmission device which is executing normally transmission and reception, and a terminal interface part 30 for controlling an input and an output between the transmission line selecting part 1 and the terminal equipment 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loop type data communication device, and more particularly to a loop type data communication device constituted by a quadruple loop.

[0002]

2. Description of the Related Art A conventional loop-type data communication device uses a double-loop transmission line so that even if a single failure occurs on the transmission line, loop-back control is performed to reconstruct the loop and the communication path Has been secured. Moreover, even if a failure occurs in a node unit, the system down is avoided by bypassing the node and disconnecting it from the communication path.

[0003]

However, in the above-mentioned conventional example, since the transmission line is only a double loop, the communication route cannot be secured when a double failure occurs on the transmission line. There was the inconvenience that communication might not be possible.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a loop type data communication apparatus which can improve the inconvenience of the conventional example and can secure a communication path especially when a double failure occurs on the transmission path.

[0005]

Therefore, in the present invention, a terminal device through which a user transmits and receives data, and a first data transmission device and a second data transmission device that perform transmission and reception with other stations via different loop transmission paths. Data transmission device, the third data transmission device, and the fourth data transmission device, a transmission path selection unit that selects each data transmission device that monitors each data transmission device and performs normal transmission and reception, and a transmission path selection unit And a terminal interface unit for controlling input / output between the terminal device and the terminal device. This aims to achieve the above-mentioned object.

[0006]

When the first data transmission device, the second data transmission device, the third data transmission device and the fourth data transmission device receive data from another station, they are sent to the transmission path selection unit. The transmission path selection unit checks the presence / absence of a reception alarm from the first data transmission device, the second data transmission device, the third data transmission device, and the fourth data transmission device, and selects a data transmission device having no reception alarm. At the same time as selecting, the data from the data transmission device is sent to the terminal device via the terminal interface unit.

[0007]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to FIGS.

In the embodiment shown in FIG. 1, the user receives data from another station via the first transmission line 51 and the terminal device 40 through which the user transmits and receives data, and also transmits the data via the second transmission line 52. First data transmission device 21 for transmitting data to another station
A second data transmission device 22 for receiving data from another station via the third transmission path 53 and transmitting data to another station via the fourth transmission path 54; and a fifth transmission path 5
A third data transmission device 23 that receives data from another station via the fifth transmission line 5 and transmits data to the other station via the sixth transmission line 56, and from another station via the seventh transmission line 57. A fourth data transmission device 24 for receiving the data of the above and transmitting the data to another station via the eighth transmission path 58,
First data transmission device 21 and second data transmission device 22
A first device selection unit 11 for selecting a data transmission device that is normally transmitting and receiving, and a third data transmission device 2
A second device selection unit 1 for selecting a data transmission device that is performing normal transmission / reception among the third and fourth data transmission devices 24.
2, a system selection unit 13 that selects a device selection unit that is performing normal transmission / reception among the first device selection unit 11 and the second device selection unit 12, and this system selection unit 13 and the terminal device 40. And a terminal interface unit 30 for controlling communication between the terminals. Here, it is also possible to connect a plurality of terminal interface units to the system selection unit 13 and install a plurality of terminal devices.

Next, the operation of this embodiment will be described with reference to FIG. Here, as an example, a case where communication is performed between the A station and the B station will be described. Here, the alphabet A following the number in the code indicates that station A is alphabet B.
Indicates station B.

The station A and the station B have the same device configuration, and the transmission data of the first data transmission device 21A of the station A is transmitted via the second transmission line 52 to the first data transmission device 21B of the station B. The transmission data of the first data transmission device 21B of the B station is sent to the first data transmission device 21A of the A station via the first transmission path 51. Second data transmission device 2 of station A
The transmission data of 2A is sent to the second data transmission device 22B of station B via the fourth transmission line 54, and the transmission data of the second data transmission device 22B of station B is transmitted via the third transmission line 53. And is sent to the second data transmission device 22A of station A.

Further, the third data transmission device 23A of station A
Is sent to the third data transmission device 23B of station B via the sixth transmission line 56, and the transmission data of the third data transmission device 23B of station B is sent via the fifth transmission line 55. It is sent to the third data transmission device 23A of the A station. The transmission data of the fourth data transmission device 24A of the A station is sent to the fourth data transmission device 24B of the B station via the eighth transmission path 58, and transmitted by the fourth data transmission device 24B of the B station. The data is sent to the fourth data transmission device 24A of the A station via the seventh transmission line 57.

[0012]. The user sends data from the terminal device 40B of station B to the terminal device 40A of station A. Then, the data from the terminal device 40B of the B station is sent to the system selection section 13B of the B station via the terminal interface section 30B of the B station.

.. The system selection unit 13B of the B station sends the data from the terminal interface unit 30B of the B station to the first device selection unit 11B and the second device selection unit 12B of the B station. Then, the first device selection unit 11B of the B station transmits the data from the system selection unit 13B of the B station to the first data transmission device 2 of the B station.
1B and the second data transmission device 22B of the B station. Further, the second device selection unit 12B of the B station receives the data from the system selection unit 13B of the B station from the third data transmission device 23 of the B station.
B and station B's fourth data transmission device 24B.

.. First data transmission device 21B of station B
The first data from the first device selection unit 11B of the B station.
The first data transmission device 21 of station A via the transmission line 51 of
Send to A. In addition, the second data transmission device 22B of the B station
The third data from the first device selection unit 11B of the B station.
The second data transmission device 22 of the station A via the transmission line 53 of
Send to A.

.. Further, the third data transmission device 2 of station B
3B sends the data from the second device selection unit 12B of the B station to the third data transmission device 23A of the A station via the fifth transmission path 55. Also, the fourth data transmission device 24B of station B sends the data from the second device selection unit 12B of station B to the fourth data transmission device 24A of station A via the seventh transmission line 57. ..

.. First data transmission device 21A of station A
Sends the data from the first data transmission device 21B of station B to the first device selection unit 11A of station A. In addition, the second data transmission device 22A of the A station receives the data from the second data transmission device 22B of the B station by the first device selection unit 11 of the A station.
Send to A.

.. Furthermore, the third data transmission device 2 of station A
3A sends the data from the third data transmission device 23B of station B to the second device selection unit 12A of station A. And
or. The fourth data transmission device 24A of the A station is the fourth data transmission device of the B station.
The data from the data transmission device 24B is sent to the second device selection unit 12A of the A station.

.. The first device selection unit 11A of station A
Data from the first data transmission device 21A of the station and the second data transmission device 22A of the station A to check the presence or absence of the reception alarm, select the data transmission device without the reception alarm, and select the data transmission device. To send to the system selection unit 13A of the A station.

.. The second device selection unit 12A of station A
Data from the third data transmission device 23A of the station and the fourth data transmission device 24A of the station A to check the presence / absence of a reception alarm, select the data transmission device without the reception alarm, and select the data transmission device. To send to the system selection unit 13A of the A station.

[0020]. The system selection unit 13A of the A station is the first station of the A station.
The data from the device selection unit 11A and the second device selection unit 12A of the A station are analyzed to check for a reception alarm, a device selection unit having no reception alarm is selected, and data from the device selection unit is analyzed. Terminal A of station A 3
It is sent to the terminal device 40A of the A station via 0A.

In this embodiment, the two stations A and B have one
Although the case where they are connected in a pair 1 has been described, by connecting the data transmission devices of a plurality of stations in a loop through the respective transmission lines 51, 52, 53, 54, 55, 56, 57, 58, It is also possible to communicate between a plurality of stations.

[0022]

Since the present invention is constructed and functions as described above, according to this, even if a double failure occurs in the transmission line,
To provide an unprecedented excellent loop-type data communication device that can switch operating systems and send and receive data from a system that is operating normally, which can improve the reliability of data communication. be able to.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing an actual usage state of FIG.

[Explanation of symbols]

 1: Transmission path selection unit 21: First data transmission device 22: Second data transmission device 23: Third data transmission device 24: Fourth data transmission device 30: Terminal interface unit 40: Terminal device

Claims (2)

[Claims] 1. A terminal device for a user to transmit and receive data, first to fourth data transmission devices for transmitting and receiving to and from other stations via different loop transmission paths, and monitoring the data transmission devices. And a terminal interface section for controlling input / output between the terminal and the transmission path selection section, which selects a data transmission apparatus that is performing normal transmission / reception. Loop type data communication device. 2. A terminal device for transmitting / receiving data to / from a user, first to fourth data transmitting devices for transmitting / receiving to / from other stations via different loop transmission paths, and the first data transmitting device. A first device selection unit that monitors the second data transmission device and selects a data transmission device that is performing normal transmission / reception, and monitors the third data transmission device and the fourth data transmission device to perform normal transmission / reception. A second device selection unit for selecting a data transmission device that is performing operation, and a system selection unit that monitors the first device selection unit and the second device selection unit and selects the device selection unit that is performing normal transmission and reception. And a terminal interface unit for controlling input / output between the system selection unit and the terminal device.