JPH0946418A - Active/standby changeover device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely bring a channel adaptor section into a standby state even when it is impossible because of a fault in the case of changeover of an active/ standby system with respect to the active/standby changeover device used to change over the active/standby state between an active equipment and a standby equipment. SOLUTION: A fault detection section 26 detects the fault of a command received by an active channel adaptor section 10, and an AND gate 30 sends a signal to forcibly reset a flip-flop 24 of a standby channel adaptor section 12 when no fault is caused and when the channel adaptor section is active. Similarly a fault detection section 28 detects a fault of a command received by a standby channel adaptor section 12, and an AND gate 32 sends a signal to forcibly reset a flip-flop 22 of an active channel adaptor section 10 when no fault is caused and when the channel adaptor section is active.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working / standby switching device for switching working / standby between working equipment and protection equipment, and more particularly to a plurality of lines provided to accommodate a plurality of lines in an exchange. The present invention relates to a working / spare switching device that switches working / spare between a unit (working line corresponding unit) and a line corresponding unit (spare line corresponding unit) that is preliminarily provided to replace one of them.

[0002]

2. Description of the Related Art FIG. 1 shows a configuration of a working / standby switching system for a line interface of an exchange. The line interface is provided, for example, for mutual conversion between the line transmission rate (for example, 4 Mbit / sec) and the transmission rate within the exchange (for example, 6 Mbit / sec). In FIG. 1, the present system includes # 1 to # 1.
A line corresponding part (working line corresponding part) 10 accommodating each call line or signal line of #n, a line corresponding part (standby line corresponding part) 12 as its spare, and each line corresponding part 10 according to an instruction from the upper processor 16. , 12 are individually controlled, and a high-order processor 16 is provided. The upper processor 16 and the line control circuit unit 14 are connected by a processor bus 18, and the line control circuit unit 14 and the line corresponding units 10 and 12 are controlled by HW / highway.
It is connected by the scanning HW20. In this system,
Upper processor 1 for accommodating and controlling the lines # 1 to #n
6 sends an active system instruction through the control HW to each active line interface 10 via the line control circuit unit 14. Also,
When the working line corresponding unit 10 detects a line failure or the like, the line control circuit unit 14 and the upper processor 16 are provided through the scanning HW.
A failure notification is sent to the standby working line support section 10 and a spare working line support section 12 is put into service, and the call and signal lines accommodated in the failed working line support section 10 are replaced by the standby line support section 12. To control the accommodation line.

In the conventional working / standby switching system, (1) when the accommodated line is switched, the working line corresponding part 10 is spared due to a control HW failure between the line control circuit part 14 and the working line corresponding part 10. When the protection line corresponding unit 12 becomes active while the activation instruction cannot be given, the line corresponding unit 2 becomes the same for the same line.
The active system may be heavily designated. as a result,
The line to be switched is accommodated and controlled by both line corresponding parts, and the normality of the call and signal line cannot be ensured. In addition, the same line is driven twice, which causes signal deterioration. On the contrary, the same occurs when switching back from the protection line corresponding unit 12 to the working line corresponding unit 10. (2) At the time of switching the accommodation line, if the active line interface 10 is not activated but the standby line interface 12 is activated due to a control error on the side of the upper processor 16, the same phenomenon as in (1) above occurs. The normality of calls and signal lines cannot be secured.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a working / standby switch which can surely make a spare even when a line interface to be spared cannot be spared due to a failure in working / standby switching. To provide a device.

[0005]

According to the present invention, a working line corresponding part for accommodating a line and a protection line corresponding part which can substitute for the working line corresponding part are included, and the working line corresponding to a command from a host device. A working / standby switching device for carrying out working and protection of the corresponding unit and the protection line supporting unit, and when there is no failure in the working command received by the working line supporting unit, a command received by the protection line supporting unit Regardless, the first forced spare circuit for forcibly spareing the protection line corresponding unit and the command received by the working line corresponding unit when there is no fault in the command of the working line received by the protection line corresponding unit. There is also provided a working / protection switching device including a second forced protection circuit for forcibly protecting the working line corresponding unit.

At the time of switching to the protection line support unit, a protection command is sent to the working line support unit to be protected, but even if it is not sent due to a control HW failure or a control error of the upper processor, the protection line support unit is supported. As long as the working instruction is normally sent to the unit, the working line corresponding unit is forcibly spared by the second forced spare circuit. Similarly, at the time of switching back from the protection line corresponding unit, the protection line corresponding unit is surely spared by the first forced protection circuit.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows the configuration of the main part of a working / standby switching device of the present invention. In FIG. 2, lines # 1 to #
The working line corresponding unit 10 for accommodating n each has a flip-flop 22 which is set (working) or reset (standby) according to a command given from the line control circuit unit 14 (FIG. 1) via the control HW. Holds a call line or signal line when it is set to the active side and controls the line. Further, the backup line corresponding unit 12 is provided with a flip-flop 24 which is set according to a command given via the control HW for each line, and the one designated in the command is set or reset. The line control circuit unit 14 (FIG. 1) is used when a failure occurs in the working line corresponding unit 10 or when a line inside the exchange fails.
After setting 0 to the protection line, the protection line corresponding unit 12 is set to the working line as a substitute for the working line corresponding unit 10 and the accommodation line switching selection is performed, whereby the protection line corresponding unit 1 is selected.
The 2nd side continues to control the same line. The fault detecting unit 26 provided in the working line corresponding unit 10 detects a fault such as a clock interruption of the control HW connected thereto and a parity error. Failure detection unit 28 provided in the protection line support unit 12
Detects a fault in the control HW connected to it.

According to the present invention, when the flip-flop 22 of the working line corresponding unit 10 is set, a signal for forcibly resetting the corresponding flip-flop 24 of the protection line corresponding unit 12 is provided on condition that there is no fault in the control HW. Send out. On the contrary, the protection line corresponding unit 12 similarly sends a signal for forcibly resetting the flip-flop 22 of the corresponding working line corresponding unit.

That is, the output of the flip-flop 22 is inputted in the positive logic and the output of the fault detecting section 26 is inputted in the negative logic to the AND gate 30 of the working line corresponding section 10, and AN
The output of the D gate 30 is connected to the corresponding forced reset input of the flip-flop 24 of the protection line corresponding unit 12. In this connection, when the output of the flip-flop 22 is at the H level (active) and the output of the fault detection unit 26 is at the L level (no fault), the output of the AND gate 30 is at the H level, and therefore the corresponding flip-flop. 24 is forcibly reset (reserved). The output of the flip-flop 24 corresponding to it is input to one input of each AND gate 32 of the protection line corresponding unit 12 in positive logic, and the output of the failure detection unit 28 is input in negative logic to the other input. The output of each AND gate 32 is connected to the forced reset input of the corresponding one of the flip-flops 22 of the working line corresponding unit 10. In this connection, when either output of the flip-flop 24 is at H level and the output of the failure detection unit 28 is at L level, AND
Since the output of the gate 32 becomes H level, the corresponding flip-flop 22 is forcibly reset.

With the configuration of the present invention, the working line interface 10
Always resets the corresponding flip-flop of the protection line corresponding unit by the current setting when there is no failure in the control HW with the host device, and sets the active system to the protection line corresponding unit 12 due to a control error of the host processor. Becomes invalid and 2
Double active system designation can be prevented. In addition, the backup line support unit 12
This is also the case when is set to be the first active.

On the other hand, when it is necessary to switch to the protection line corresponding part in the working line corresponding part 10 due to the line failure, the flip-flop 2 of the working line corresponding part 10 due to the control HW failure.
When 2 cannot be controlled, the output of the fault detection circuit 26 of the working line support unit 10 suppresses the forced reset output to the protection line support unit 12, and the working line support is set by setting the working system to the protection line support unit 12. The flip-flop 22 of the unit 10 is forcibly reset. Therefore, the accommodated line can be switched from the working line corresponding unit to the protection line corresponding unit. The same can be applied to the case where the backup line corresponding unit is pulled back to the working line corresponding unit by the recovery of the working line corresponding unit.

FIG. 3 shows a case where the line corresponding units 10 and 12 perform the function of mutual conversion between the transmission rate of the line to be accommodated in the exchange (6 Mbit / sec) and the transmission rate in the exchange (8 Mbit / sec). 2 shows a configuration of active / standby switching of. 3 in FIG.
Three line-corresponding parts 10 for performing 6M-8M conversion for a line and one spare line-corresponding part 12 as an alternative are shown.

When there are no faults in the three line interface units 10 or the 8M-HWs # 0 to # 2 connected to them, all the active line interface units 10 are operated according to a command from the line control circuit 14 (FIG. 1). It is in operation. At this time, the protection line corresponding unit 12 is spared, and at this time, the protection line corresponding unit 12 is operated by a relay switch (described later) in the 6M-HW #.
The loop of 8M-HW # 3 is closed (short-circuited) by being separated from 0 to # 2. If any one of the working line corresponding units 10 or 8M-HW # 0 to # 2 fails, the protection line corresponding unit 12 is used as a substitute for the working line corresponding unit 10 in which the failure is detected according to the instruction from the line control circuit 14. Is put into practical use. That is, the working line interface 1 in which the failure is detected
8M-HW connected to 0 is short-circuited and 6M-HW is disconnected. The separated 6M-HW is the line interface 12
, And 6M-8M conversion is performed with 8M-HW # 3.

FIG. 4 shows a detailed configuration of one of the working line corresponding units 10 and the protection line corresponding unit 12 of FIG. The working line interface 10 includes an HW controller 34 for controlling the control HW and scanning HW with the host device, a control HW failure detector 36 for detecting a clock break of the control HW, and a parity error, and 8M-HW and 6.
A signal for forcibly preserving the speed conversion circuit 38 with the M-HW, the relay switch 40 for connecting / disconnecting the 6M-HW, the flip-flop 22 for controlling the relay switch 40, and the protection line corresponding unit 12 is transmitted. AND to send
It is composed of a gate 30. The protection line interface 12 accommodates the HW controller 42, the control HW failure detector 44, and the speed conversion circuit 46 having the same functions, as well as 6MHW # 0 to # 2 accommodated in each working line interface. Relay switch 48 for controlling each relay switch 48, a flip-flop 24 for controlling each relay switch 48, and an AND gate 32 for sending a signal for forcibly spareing the substitute working line corresponding unit 10. The protection line corresponding unit 12 further operates any one of 6M-HW # 0 to # 2 via the relay switch 48 when the protection line corresponding unit 12 and the 8M-HW # 3 connected thereto are activated. It has a relay switch 50 connected to the -6M conversion unit 46, which short-circuits 8M-HW # 3 and a flip-flop 52 which controls the relay switch 50, along the path shown by the dotted line in the figure when they are spared. Even when the working line corresponding unit 10 is spared, the relay switch 40 causes 8M-in the route of the dotted line in the figure.
HW is shorted.

Here, 6M-HW is sent to the working line interface 10.
In order to accommodate and control # 0, the active system is set by the control HW # 0. At this time, if there is no fault in the control HW, a forced reset signal is sent to the protection line corresponding unit 12, and the corresponding flip-flop 24 for the relay switch 48 is forcibly reset. As a result, the active system setting to the protection line corresponding unit due to the control error on the upper processor side can be prevented because the flip-flop 24 is constantly being reset. Also, when the working line fails or the working line corresponding part fails, switching to the protection line corresponding part is performed.
When the flip-flop 22 cannot be spared due to a failure, the forced reset signal is suppressed so that the flip-flop 22 of the failed system (switching source) can be forcibly reset and spared by setting the active system to the spare line corresponding unit. You can do it.

[0016]

As described above, according to the present invention, in the working / spare switching device of the line interface, by interlacing the forced reset signal between the line interface, the interface with the host device is established. Even if the standby system cannot be switched due to a failure, the standby system can be forcibly switched by setting the active system to the switching destination, and the active system due to a control error on the upper processor side,
It is also possible to prevent the setting of the dual active system of the standby system.

[Brief description of drawings]

FIG. 1 is a diagram showing a working / standby switching configuration of a line interface.

FIG. 2 is a diagram showing a configuration of a main part of an active / spare switching device of the present invention.

FIG. 3 is a diagram showing a working / standby switching configuration when a line corresponding unit achieves a 6M-8M conversion function.

FIG. 4 is a diagram showing a detailed configuration of a working line support unit and a protection line support unit of the present invention.

[Explanation of symbols]

 22, 24, 52 ... Flip-flop 30, 32 ... AND gate

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Ichiro Arita 1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Manabu Yajima 1-6-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation

Claims (3)

[Claims] 1. A working line corresponding unit (10) for accommodating a line and a protection line corresponding unit (12) which can be a substitute for the working line corresponding unit, and the working line corresponding unit according to a command from a host device. A working / standby switching device for carrying out working and protection of a protection line corresponding part, wherein when there is no failure in the working command received by the working line supporting part, regardless of the command received by the protection line supporting part. A first compulsory protection circuit (26, 30) for forcibly reserving the protection line corresponding part, and a command received by the working line supporting part when there is no fault in the command for the working conversion received by the protection line corresponding part. Regardless of this, a working / spare switching device comprising a second forced spare circuit (24, 32) forcibly spareing the working line corresponding part. 2. The working line corresponding unit comprises a plurality of working line corresponding units for accommodating a plurality of lines, and the protection line corresponding unit is one of the plurality of working line corresponding units designated in the command. The second forced protection circuit forcibly forces the working line support unit specified in the command when the working line command received by the protection line support unit is not faulty. The device according to claim 1, which is to be spared. 3. A plurality of first flip-flops which are provided respectively corresponding to the plurality of working line corresponding units, and which are set and reset in accordance with working and protection commands received by the working line corresponding units, respectively. And corresponding to the working line corresponding units specified in the command in response to the working and protection commands received by the protection line corresponding unit. A plurality of second flip-flops that are set and reset, respectively, wherein the first forced backup circuit detects a plurality of first faults in the commands received by the plurality of working line corresponding units, respectively.
Fault detection circuit, each output of the first fault detection circuit and each output of the plurality of first flip-flops are connected to its input, and its output corresponds to the plurality of second flip-flops. A plurality of first gate circuits connected to the input for forcibly resetting the ones, wherein the second forced backup circuit detects a fault in the command received by the backup line corresponding unit. A second fault detection circuit,
One input is connected to the output of the second fault detection circuit and the other input is connected to each of the outputs of the plurality of second flip-flops, the output of which corresponds to the plurality of first flip-flops. 3. A device according to claim 2 including a plurality of second gating circuits connected to the inputs for forcing a reset of the ones.