JPH01284131A - Switching control system - Google Patents

Abstract

PURPOSE:To enable to switch a first living circuit to a spare circuit in a switching section where the first living circuit can be switched to the spare circuit even if both the first living circuit and the spare circuit fall into trouble at one time and at the same spot by providing every switching section not provided with a master control part with an auxiliary master control part. CONSTITUTION:A second and a third switching sections not provided with the master control part 10 are provided with the auxiliary master control parts 15, 16. When both the first living circuit and the spare circuit fall into the trouble at the same time and at the same spot, for instance, at a point B, a slave control part 8 recognizes this through information from terminal repeaters 2, 4, and inserts the nearest (in the same station) auxiliary master control part 15 into the circuit of a service bit of the spare circuit. Accordingly, trouble information from the slave control parts 7-1, 8-1, 7-2, 14 can be received by the auxiliary master control part 15, and a switching instruction based on the received trouble information can be transmitted to these slave control parts. Thus, in the second and the third switching sections, the first living circuit can be switched to the spare circuit even if the first living circuit falls into the trouble.

Description

[Detailed Description of the Invention] [Summary] Terminal repeaters (hereinafter referred to as L i”E) are installed at both ends of the transmission line.
, and at least one of the LTEs is configured with a slave control unit that switches between the first working line, which is to be dropped/inserted, and the protection line, respectively, according to instructions from the master control unit, using switching devices on both sides. A plurality of switching sections are connected in series, and a second working line is further provided between the switching devices at both ends of the plurality of switching sections connected in series,
With respect to a digital transmission system that uses switching devices at both ends to switch between the second working line and a protection line in which protection lines of all switching sections are connected in series, the first working line and the protection line are simultaneously connected at the same location. In switching sections where the first working line can be switched to the protection line even if a failure occurs, a slave An auxiliary master control unit is provided that can output a switching command to the slave control unit that is to operate the switching device based on a report from the control unit, and the slave detects that both the first working line and the protection line have failed. The controller is configured to insert the nearest auxiliary master controller into the service bit line of the protection line.

[Industrial application field]

The present invention has LTE at both ends of the transmission line, and at least one LTE is dropped/inserted.
The working line and the backup line are connected using switching devices on both sides.
A plurality of switching sections constituted by slave control sections that each switch according to a command from a master control section are connected in series, and a second working line is further connected between the switching devices at both ends of the plurality of series-connected switching sections. The second working line and the protection line in which the protection lines of all switching sections are connected in series are controlled by the respective slave control units using the switching devices at both ends according to the instructions from the master control unit. This invention relates to improvements in switching control methods for switching digital transmission systems.

[Conventional technology]

A conventional example will be explained below using figures.

FIG. 3 is a block diagram of a conventional digital transmission system, and FIG. 4 is a block diagram of a conventional slave control section.

The digital transmission system shown in FIG. 3 is constructed as described below.

That is, the first working line has LTEI, 2 at both ends of the transmission line, and at least one LTE is dropped/inserted, and the protection line has LTE 3.4 at both ends of the transmission line. Using device 5.6, when the first working line is in trouble, the service bit of the protection line is used to notify the master@Obeko0, and the service bit of the protection line from the master control unit 10 is sent. The slave control units 7'' and 8 are switched according to the switching command used.
A plurality of switching sections constituted by ゛ are connected in series with a first switching section, a second switching section, and a third switching section.

Moreover, switching devices 5 at both ends of the plurality of switching sections connected in series
There is also a second working line with LTEI2.13 at both ends of the transmission line between ' and 11.

When the second working line is in failure, the slave control unit 7 or 14 notifies the master control unit IO using the service bit of the protection line, and the service bit of the protection line from the master control unit 10 is notified. Under the control of the slave control unit 7.14, the switching devices 5 and 11 at both ends are used to connect the second working line and the protection lines of all switching sections in series. It is designed to switch between lines.

Next, the slave control sections 8' and 7'-1 will be explained in detail using FIG. 4 as representative examples of slave control sections.

When a transmission path failure is detected in LTE2, the control unit 21' of the slave control unit 8' is notified.

Then, the control unit 21° sets the switch sw5 to the dotted line side,
The transmitting unit 24 transmits failure information indicating that a transmission path failure has been detected in LTE 2 to the master control unit 10 shown in FIG. 3 via the buffer 25 using the service bit of the protection line.

Further, when a transmission path failure is detected in LTE 1-1, the control unit 26 of the slave control unit 7'-1 is notified.

Then, the control unit 26 sets the switch SW6 to the dotted line side, and the transmission unit 29 transmits failure information indicating that a transmission line failure has been detected in LTEl-1 to the master control unit via the buffer 30.25 using the service bit of the protection line. Send to 10.

When the master control unit 10 receives the failure information, it determines which part should be switched to the protection line.

As a result, for example, when switching a working line with LTE 1.2 on both ends of the transmission line to a protection line with LTE 3.4 on both ends of the transmission line, the service bit of the protection line is used to switch the slave line shown in Figure 3. A switching command is sent to the control unit 7.8.

Then, the receiving section 23 of the slave control section 8' receives this, and the control section 21° switches the switches SWI and S of the switching device 6.
Switch W2 to the dotted line side and switch to use the protection line instead of the working line.

At this time, the slave control unit 7 also operates in the same manner as described above, and the switching device 5 switches to use the protection line instead of the working line.

Although the slave control unit 7'-1 receives the switching command from the master control unit 10 at the receiving unit 28, it does not take any action because it is not addressed to its own station.

Also, when a fault in the second working line is detected at LTEL2.13 in FIG. 3 and the slave control unit 7 or 14 is notified,
This information is notified to the master control unit 10 using the service bit of the protection line.

Then, the master control unit IO sends a message to the slave control unit 7.14 using the service bit of the protection line.
A command is issued using the switching device 5.11 to switch the working line of 1 to a protection line in which the protection lines of all switching sections are connected in series.

With this command, the slave control units 7 and 14 switch the switching device 5
．． Switch to the backup line at 11.

In addition, when a fault in the protection line is detected in LTE 4, 3-1, the control unit 21' of the slave control unit 8'' and the slave control unit 7
The slave control unit 8' side notifies the master control unit IO that the backup line is faulty, but at this time, the switching command is not sent to the slave control unit. Not done.

(Problem to be Solved by the Invention) However, for example, if the first working line and the protection line fail at the same time at point A in the first switching section in FIG. Failure information cannot be reported to the master control unit 10 via the master control unit 10.
slave control unit 7'-1, 8'- via the protection line.
1,7'-2°14 could not be commanded, and the second. In the third switching section, there is a problem in that the line cannot be switched even though it is possible to switch to the protection line when the working line becomes faulty.

The present invention provides a switching control method that enables switching in a switching section where the first working line can be switched to the protection line even if the first working line and the protection line fail at the same location at the same time. It is an object.

[Means to solve the problem]

FIG. 1 is a block diagram of the principle of the present invention.

As shown in FIG. 1, the digital transmission system to which the present invention is applied has LTE 1 and 2 at both ends of the transmission line, and at least one LTE is a first working line that is dropped/inserted; A switching section consisting of slave control units 7 and 8 that respectively switch a protection line with LTE 3.4 at both ends using switching devices 5.6 on both sides is a first switching section and a second switching section. , a third switching section..., and a second switching section having LTE 12.13 at both ends of the transmission line is further connected between the switching devices 5 and 11 at both ends of the plurality of switching sections connected in series. There is a working line, and the second working line and a protection line in which protection lines of all switching sections are connected in series are connected to switching devices 5.1 at both ends.
1 and is configured to be switched under the control of the respective slave control units 7 and 14.

In addition, each slave control unit notifies the master control gate unit 10 using the service bit of the protection line when the first working line is in failure, and performs switching using the service bit of the protection line from the master control unit 10. Due to old age, each switching device switches the first working line to a protection line.

In the above-mentioned digital transmission system, an auxiliary master control unit is capable of outputting a switching command to a slave control unit that is to operate a switching device based on fault information from a slave control unit for each switching section that does not have the master control unit 10. 15 and 16, and the slave control unit that detects that both the first working line and the protection line have failed inserts the nearest auxiliary master control unit into the line of the service bit of the protection line. do it like this.

[For production]

According to the present invention, if the first working line and protection line fail at the same location at the same time, for example, at the four points in FIG. An auxiliary master control unit 15 (in the same station) is inserted into the service bit line of the protection line.

Therefore, slave control unit? -1,8-1,7-2,14
The second failure 11 can be received by the auxiliary master control unit 15, and the switching command based on the received failure information can be sent to the slave control units 7-1.8-1.7-2.14. In the third switching section, even if the first working line fails, it is possible to switch to the protection line.

〔Example〕

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 2 is a block diagram of a slave control section and an auxiliary master control section according to an embodiment of the present invention.

As an example, in the digital transmission system shown in FIG. 3, as shown in FIG. If the slave control unit 8.8-1 determines that both the first working line and the protection line have failed, the nearest auxiliary master control unit 1
5.16 is inserted into the service bit line of the protection line.

Therefore, in order to explain the details of the slave control section and the auxiliary master control section, FIG. 2 shows the slave control section 8.7-1 and the auxiliary master control section 15 in FIG. Explain.

The difference between FIG. 2 and FIG. 4 is that there is an auxiliary master control unit I5 that can receive fault information from the slave control unit and output a switching command to the slave control unit that is to operate the switching device; A control section insertion section 20 is provided, and L
If the control unit 21 of the slave control unit 8 receives a failure notification from the TEs 2 and 4 at the same time, the control unit 21 causes the auxiliary master control unit 15 to connect to the backup line via the master control unit insertion unit 20. The point is that the service bit is inserted into the line.

That is, when the failure information of the first working line and the protection line are simultaneously input from LTE 2.4 to the control unit 21 of the slave control unit 8, the control unit 21 inputs the switch SW7 of the master control unit insertion unit 20. SW8 is on the dotted line side, and the auxiliary master control unit 1
5 is inserted into the service bit line of the protection line.

Then, the slave control section 7-1.8-1.7- in FIG.
2.14 can be received via the buffer 30 and switch SW7 of the slave control unit 7-1, and the slave control unit 7-1.8-1.7-2.14
The destination switching command is sent to switch SW8. of the master control unit insertion unit 20. The data can be sent via the OR circuit 31 using the service bit of the protection line.

The operation of the auxiliary master control section 15 is to transmit fault information from the slave control section to the receiving section 3 via the switch SW7.
2, it is sent to the processing unit 34, and the processing unit 34 determines which slave control unit is to be switched based on the failure information, and the determination is made using the service bit of the protection line via the transmission unit 33 and switch SW8. A switching command is sent to the slave control unit that has been installed.

Therefore, the first working line and the protection line become faulty at the four points in FIG. .8-1゜7-2.14 Even if it becomes impossible to notify the slave control unit 7-1.8-1.7-2.1
The failure information from 4 is sent to the auxiliary master control unit 15,
The switching command from the auxiliary master control unit 15 can be notified to the slave control units 7-1.8-1.7-2.14. Even if one working line fails, LTE3 is available at both ends.
-1.4-1 It becomes possible to switch to a protection line with 4-1. This can be similarly switched in the third switching section.

〔Effect of the invention〕

As explained in detail above, according to the present invention, even if the first working line and the protection line fail at the same location at the same time, switching is not possible in the switching section where the first working line can be switched to the protection line. It has the effect of making it possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the principle of the present invention; FIG. 2 is a block diagram of a slave control unit and auxiliary master control unit according to an embodiment of the present invention; FIG. 3 is a block diagram of a conventional digital transmission system; The figure is a block diagram of a conventional slave control section. In the figure, 1~4.1-1~4-1.1-2~4-2.12゜13
is a terminal repeater, 5, 6. 5-1. 6-1. 5-2! Is the switching device? , 8.7-1.7-2.8-1.7'-1°7''
-2,8° -1, 14 are slave control units, 10 are master control units, 15.16 are auxiliary master control units, 20 are master control unit insertion units, 21.26 are control units, 22.25.27 .30 is a buffer, 24.29.33 is a transmitting section, 23.28.32 is a receiving section, 34 is a processing section, and SW1 to SW8 are switches. Slave Article 1qJP Naedo 0 Block Diagram Figure 4

Claims (1)

[Scope of Claims] A first working line, which has terminal repeaters (1, 2) at both ends of the transmission line, and at least one terminal repeater is drop/insert, and a protection line, Using the switching devices (5, 6) on both sides, when the first working line is in failure,
The master control unit (10
), and in response to a switching command from the master control unit (10) using the service bit of the protection line, the switching section consisting of the slave control units (7, 8) that respectively switch is switched to the first switching section. section, a second switching section, a third switching section, etc., and a second working section is further connected between the switching devices (5, 11) at both ends of the switching sections connected in series. The second working line and the protection line in which the protection lines of all switching sections are connected in series are connected to each slave control unit (7) using the switching devices (5, 11) at both ends.
, 14), for each switching section that does not have the master control section (10), a switching command is sent to the slave control section that is to operate the switching device based on a report from the slave control section. An auxiliary master control unit (15, 16) capable of outputting is provided, and the slave control unit detects that both the first working line and the protection line have failed, and switches the nearest auxiliary master control unit to the protection line. A switching control method characterized by inserting a service bit into a line.