JPH0821877B2 - Switching control method for the active and standby packages that make up the redundant system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary of the Invention] The present invention relates to a switching control method of a working package and a standby package which form a redundant system, and an object thereof is to make it possible to easily take a redundant configuration even in a package having no mounting position. A redundant system that is connected to a time switch (TSW) that has the function of time-division-switching time-division-multiplexed input signals that are time-division-multiplexed using time-slots in a frame to configure a redundant system. In the standby package switching control method, a specific signal for inserting a signal indicating whether or not there is a failure in its own package and a signal indicating whether the own package is in the active or standby mode into the active and standby packages, respectively. A time slot is provided, and the active package that detects a failure sends a signal indicating the occurrence of an external failure to a specific signal in the frame. The time switch unit (TSW) sends the signal of the specific time slot back to the active package and the standby package, and in response to this, the standby package fails in the active package. Knowing that, while switching its own standby state to the active state, a signal indicating that it is active is inserted into a specific time slot in the frame and sent to the time switch section (TSW), and the time switch section (TSW) The signal of the specific time slot is sent back to both packages, and in response to this, the package in the working state and in which the fault has occurred switches itself to the standby state and at the same time sends a signal indicating that it is in the standby state in the frame. Insert it in a specific time slot and insert the time switch (TS
Then, the time switch unit (TSW) sends back the signal of the specific time slot to both packages and completes the switching between the active and standby packages.

[Industrial applications]

The present invention relates to a switching control system for a current and standby packages that form a redundant system.

It is often the case that the communication device has a structure in which the system is duplicated and one is used as the active system and the other is used as the standby system, and when the active system becomes an obstacle, the system is immediately switched to the standby system to continue communication. The present invention relates to such active / standby package switching control.

[Conventional technology]

Conventionally, when two packages are used in a redundant configuration, the mounting positions of these two packages are fixed and the corresponding terminals of each package are fixedly connected by a printed circuit board pattern or strap wiring. A switching signal is sent through the wiring to switch between active and standby.

Explaining in FIG. 7, 10 and 10A are two packages,
In this example, 10 is in use and 10A is in standby. These packages include an output control unit 12 (subscript A is omitted as appropriate), a switching control unit 14, a failure detection unit 16, and the like. When the detector 16 of the active package 10 detects a failure, the switching control unit 14 causes the output control unit 12 to stop the data output, and also sends a signal to the standby switching control unit 12A through the wiring 1 (the package 10 fails. , A signal indicating that the data transmission has been stopped. Upon receiving this, the switching control unit 12A causes the output control unit 14A to start data output (the standby system does not output,
It is operating), and the package 10A is switched to the current one.
Thus, the active system changes from package 10 to 10A, and the standby system changes from package 10A to 10.

As described above, in the conventional switching method, since the switching signal is transmitted through the fixed wiring l to perform the switching, the wiring l cannot be provided in the package in which the mounting position is free. Cannot adopt a redundant configuration.

As shown in FIG. 5, the time switch TSW,
Interfaces IFP _{1 to} IFP ₄ and interface IFP ₃
And / or connect to a terminal (PBX in this example) via IFP ₄ ,
The interfaces IFP ₁ and IFP ₂ are connected to the transmission lines TL ₁ and TL _{2 shown} in FIG. A and B in FIG. 4 are terminal stations, and the transmission line between these terminal stations is duplicated in TL ₁ and TL ₂ . Where time switch TSP
Has a time-division switching function for connecting arbitrary time slots by converting the time-division multiplexed input signals using the time slots in the frame in time sequence specified in time slot units.

The 6th shelf contains the package of this synchronous terminal station.
As shown in the figure, there are time switch (TSW), interface (IF), and so on. It is easy to duplicate the time switch, which is a common part, and these packages TSW ₀ and TSW ₁ may be arranged adjacent to each other at a predetermined position and the wiring 1 may be provided. On the other hand, the interface package can be inserted into the shelf at any position (appropriately inserted by the user) and can be placed anywhere in the IF shelf, and is not fixed. Duplicate is difficult.

[Problems to be Solved by the Invention]

In the method of switching by sending the switching signal through the wiring l as described above, if the package insertion position is fixed, the wiring l can be easily set to switch between the active / standby state and a redundant configuration can be taken. However, in the free package, the wiring l cannot be set and it is difficult to duplicate the wiring.

An object of the present invention is to improve such points so that a redundant structure can be easily formed even in a package having no mounting position.

[Means for solving the problem]

In the present invention, as shown in FIG. 1, a switching control signal is sent through the time switch unit 20.

The active package 10 that has detected a failure by the detection unit 16 inserts the failure information into a specific time slot and sets the time switch unit 20.
Send to. The time switch unit separates the transmission information and the failure information, and sends the failure information back to the active and standby packages 10 and 10A. When the standby package 10A receives this, it switches itself to the active mode, and the active package 10 stops sending the transmission information and switches to the standby mode.

[Action]

In the present invention, the switching control signal is transferred according to the fault information by utilizing the empty time slot of the transmission information, and the active / standby switching is performed by this. No matter where the active / standby package is inserted into the shelf, the signal line for transmission information (transmission line information) is indispensable, so be sure to send a switching control signal to perform active / standby switching. Therefore, it is possible to reliably and easily form a redundant system even in a package in which the mounting position is free.

〔Example〕

FIG. 2 shows an embodiment of the present invention. The active / standby packages 10 and 10A are the interface packages IFP ₁ and IFP shown in FIG.
₂ , the time switch unit 20 to the same TSW, the connection destination package 30
Corresponds to the interface package IFP ₃ .

The active / standby package 10 / 10A has an output control unit 12 (subscript A).
Are appropriately omitted), the switching control unit 14, the fault detection unit 16a in its own package, the fault detection unit 16b of the signal transmitted through the transmission line TL, the speed conversion unit 17, the multiplexer 18, and the demultiplexer 19. Prepare

The bit rate of the transmission line TL is 1.5 Mb / s or 6.3 Mb / s, the time switch TSW side is 8 Mb / s, and speed conversion is required to connect them. The speed conversion units 17, 17A perform this speed conversion.

The format of the signal between the packages 10 and 10A and the time switch unit 20 is as shown in FIG.
μS, 128TS (time slot), the main signal as communication information occupies most of one frame except both ends, and the front end 1
~ 4TS and the rear end 125-128TS are dummy. In the present invention, fault information is sent using the front end portions 1 to 4TS. Ie 1
~ The first bit of 4 bits to be inserted in 4TS is package 10
Is the active or standby mode, the second bit is whether a fault is detected in the package 10 (whether 16a, 16b generate a fault detection output), and the third bit is whether the package 10A is in the active or standby state.
The fourth bit is a bit indicating whether or not a failure is detected in the package 10A.

The switching control unit 14 sets the second bit to a fault, for example, "1" when the fault detection units 16a and 16b generate an output, and
If 10 is in use, the first bit is set to "0", for example. Similarly, the switching control unit 14A sets the fourth bit as a fault when the fault detection units 16aA and 16bA produce an output, which is set to "1" in this example, and when the package 10A is on standby, the third bit is set to "1" in this example. "I will. This is done via multiplexers 18, 18A. That is, the switching control unit prepares the above data, operates the multiplexer, and sends the above bits together with the main signal from the output control unit 12 when in use, and sends only the above bits when in standby.

The demultiplexers 19 and 19A receive the signal of the above format from the time switch unit 20 and the main signal is the speed conversion unit 17
To the switching control unit.

When the package 10 is currently in use and the package 10A is in standby and the failure detection units 16a and 16b of the active package 10 detect a failure, the switching control unit 14 sets the second bit to failure "1". The time switch unit 20 sends the main signal to the connection destination package 30, and the failure information (the first to fourth bits) together with the signal sent from the connection destination package 30 (which also becomes the main signal). Send to 10A.

The demultiplexer 19A of the package 10A sends the first and second bits of the fault information to the switching control unit 14A. Package 10
When receiving the first and second bits indicating the active or fault of the switching control section 14A, the switching control section 14A switches the own system package 10A to the active side and operates the multiplexer 18A to output the output control section 12A (main signal).
Then, the fault information in which the third bit is the active "0" and the fourth bit is the normal "0" is transmitted. In the package 10, the demultiplexer 19 sends the 3rd and 4th bits of the fault information to the switching control unit 14, and in response to this, the switching control unit 14 sets its own system to standby "1", fault "1", and output control unit. The output of 12 is not transmitted, but only the fault information is transmitted.

In this way, the active and standby switching of the packages 10 and 10A is performed. The signal from the time switch unit 20 is package 10,10A
Since they are always sent to these packages regardless of where they are mounted, switching signals can be reliably delivered and received simply by setting the time slot that contains the active / standby and fault / normal information. Duplication becomes possible.

The switching control unit 14 may immediately prohibit the transmission of the main signal when a failure is detected in the package 10. The fault package 10 returns the second bit to “0” if it becomes normal in the subsequent repair, and sends the first and second bits which are the standby “1” and the normal “0” to prepare for the fault of the active package. .

Note that the packages 10 and 10A also perform format conversion. Also, the interfaces IFP ₃ and IFP ₄ on the terminal side in FIG.
Is for the purpose of sharing the processing of signals between TSP and terminals.

The signal format of the synchronizing terminal station is as shown in FIG. 3 (a), and there is no frame synchronizing bit. Frame synchronization is third
As shown in FIG. 6B, a separate signal, in this example, an 8 KHz clock is used.

〔The invention's effect〕

As described above, according to the present invention, it is possible to provide a redundant configuration for a mounting position-free package, which is difficult for the redundant configuration.

[Brief description of drawings]

1 is a principle diagram of the present invention, FIG. 2 is a block diagram showing an embodiment of the present invention, FIG. 3 is an explanatory diagram of a signal format, FIG. 4 is an explanatory diagram of a duplication system, and FIG. FIG. 6 is a block diagram showing a configuration of a synchronization terminal station, FIG. 6 is an explanatory diagram showing a package arrangement state on a shelf, and FIG. 7 is a block diagram showing a conventional example of a redundant configuration.

Claims (1)

[Claims] 1. Redundancy for connecting to a time switch unit (TSW) having a function of time-division-switching time-division-multiplexed input signals time-division-multiplexed using time-slots in a frame to operate an interface. In the switching control method of the active and standby packages that make up the system, a signal indicating whether or not a failure has occurred in its own package and a signal indicating whether its own package is the active or standby package are inserted into each of the active and standby packages. A specific time slot is provided to enable the current package to detect a failure, insert a signal indicating the occurrence of the failure into a specific time slot in the frame, and send it to the time switch section (TSW). Sends the signal for that particular time slot back to the active and standby packages, which in turn receives the standby package. Knows that a failure has occurred in the active package, switches its standby state to the active state, and inserts a signal indicating that it is active into a specific time slot in the frame and sends it to the time switch unit (TSW). , Time switch (T
SW) sends back the signal of that specific time slot to both packages, and in response to this, the package that was in the working state and failed earlier switches itself to the standby state and sends a signal indicating that it is in the standby state. Insert it into a specific time slot in the frame and send it to the time switch unit (TSW), and the time switch unit (TSW) sends back the signal of that specific time slot to both packages, and completes the switching between the active and standby packages. A switching control method for the active and standby packages that make up the redundant system.