JPH0398320A - Switching control system for active/standby package constituting redundant system - Google Patents

Abstract

PURPOSE:To attain redundant constitution to a package being in a free packaging position by utilizing an idle time slot of transmission information so as to transfer a switching control signal according to fault information and applying changeover of active/standby system. CONSTITUTION:An active package 10 detecting a fault at a detection section 16 inserts fault information at a specific time slot and sends the result to a time switch section 20. The time switch section separates the information into transmission information and the fault information and sends back the fault information to active and standby packages 10, 10A. Upon the receipt of the information, the standby package 10A select the active mode by itself and the active package 10 stops the transmission of transmission information and selects itself to be in the standby mode. Thus, even when the active and standby packages are inserted in any position of a shelf, since a signal line for the transmission information is arranged without fail, the active/standby changeover is attained by surely sending a switching control signal. Thus, redundancy constitution is easily taken even in a package being in a free packaging position.

Description

[Detailed Description of the Invention] [Summary of the Invention] Regarding a switching control system between active and standby packages that constitute a redundant system, an object of the present invention is to enable redundancy precautions to be easily taken even for packages whose mounting positions are free. In a switching control system for active and standby packages that are connected to a time switch unit to perform interface operations and are duplicated to form a redundant system, the active package that detects a failure transmits the failure signal to a specific time slot. The time switch section sends it back to the current and standby packages, and upon receiving this, the standby package is switched to the current package, and the current package is switched to the standby package.

[Industrial application field]

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

Communication devices are often configured to have two systems, one for active use and one for standby, so that if the active system becomes in trouble, it is immediately switched to the standby system to continue communication. The present invention relates to switching control between active and standby packages.

[Conventional technology]

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

To explain this with reference to FIG. 7, 10 and IOA are two packages; in this example, 10 is the active one and IOA is the standby one. These packages include an output control section l2 (subscript A is omitted as appropriate), a switching control section 14, a failure detection section 16, and the like. When the detector 16 of the active package IO detects a failure, the switching control unit 14 causes the output control unit 12 to stop data output, and also sends a signal (the package IO detects the failure) to the standby switching control unit 12A through the wiring 1. , a signal indicating that data transmission has been stopped). Upon receiving this, the switching control section 12A causes the output control section 14A to start data output (
The standby system also does not output, but is still operating), and switches the package IOA to the active one. In this way, the active system changes from package 10 to IOA, and the standby system changes from package IOA to 10.

In this way, in the conventional switching method 2, switching is performed by transmitting the switching signal through the fixed wiring l, so it is not possible to provide the wiring l in a package where the mounting position is free, and as a result, switching and double redundant configuration cannot be adopted.

At the synchronous terminal station, as shown in Fig. 5, time switches TSW,
The interface IFP. and or IFP. Connect to the terminal (PBX in this example) via the interface IFPI, IFP2
are connected to the transmission lines TL and TL2 in FIG. A and B in this figure 4 are terminal stations, and the transmission lines between these terminal stations are TL, TL.
．． will be duplicated.

As shown in FIG. 6, the shelf accommodating the package of this synchronous terminal station is divided into one for the time switch (TSW), one for the interface (IF), and so on.

It is easy to duplicate the time switch, which is a common part, and these packages TSW. , TSW, are placed adjacent to each other at predetermined positions, and the wiring l is provided. On the other hand, the interface package can be inserted into the shelf at any position (the user inserts it appropriately), and can be inserted anywhere within the IF shelf; it is not fixed, so it is not possible to provide wiring, and Duplication is difficult.

[Problem to be solved by the invention]

In this method of switching by sending a switching signal through the wiring, if the package insertion position is fixed, the wiring can be easily changed.
can be set to switch between active/standby and create a redundant configuration, but in a free package where the insertion position is arbitrary, the wiring l cannot be set and duplication is difficult.

It is an object of the present invention to improve the above points and to enable a redundant configuration to be easily established even in a package where the mounting position is free.

[Means to solve the problem]

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

The active package 10 that has detected a fault in the detection unit 16 inserts fault information into a specific time slot and sends it to the time switch unit 20. The time switch section separates transmission information and failure information, and the failure information is used in the current and standby packages 10 and IOA.
send it back to When the standby package IOA receives this, it switches itself to the active package, and the active package IO stops sending transmission information and switches to the standby mode.

[Effect]

In the present invention, the switching control signal is transferred according to the fault information using the vacant time slot of the transmission information, and the switching control signal is transferred between the currently used and
Perform standby switching. No matter where the active or standby package is inserted on the shelf, the signal line for transmission information (transmission line information) is always installed, so the switching control signal is reliably sent to perform active/standby switching. This makes it possible to reliably and easily configure a redundant system even with packages that can be mounted anywhere.

〔Example〕

FIG. 2 shows an embodiment of the present invention. The active/standby package 10, IOA is the interface package IF in Figure 5.
P. , IFP. , the time switch section 20 is connected to the same TSW,
The connection destination package 30 is the interface package IF
P. corresponds to

Active/standby package 1 0/1 0A is output control unit 1
2 (the subscript A is omitted as appropriate), a switching control unit 14, a failure detection unit 16a in its own package, a failure detection unit 16b for signals transmitted through the transmission line TL, a speed conversion unit 17,
It includes a multiplexer 18 and a demultiplexer 19.

The bit rate of the transmission line TL is 1. 5 Mb/s or 6. 3 Mb/s, time switch TSW side is 8
Mb/S requires speed conversion to connect the two.

The speed converter 17.17A performs this speed conversion.

The format of the signal between the package 10, IOA, and time switch unit 20 is as shown in Figure 3, where one frame is 125 μS, 128 TS (time slot), and the main signal, which is communication information, excludes both ends of one frame. The front end portions 1 to 4 TS and the rear end portions 125 to 128 TS occupy most of the space.

In the present invention, the front end portions 1 to 4TS are used to send failure information. That is, the first bit of the four bits inserted in TS 1 to 4 indicates whether the package IO is currently in use or standby, and the second bit indicates whether a failure has been detected in the package 10 (16a, 16b).
has produced a failure detection output), the third bit indicates whether the package IOA is currently in use or standby, and the fourth bit indicates whether a failure has been detected in the package IOA.

The switching control unit 14 sets the second bit to a fault, for example, “1” when the fault detection units 16a, 1.6b generate an output, and sets the l-th bit to, for example, “0” if the package IO is currently in use.
Make it ゛. Similarly, the switching control section 14A is the fault detection section 16a.
When A, 16bA produces an output, the 4th bit above is disturbed,
In this example, it is set to "1°", and if the package 10A is on standby, the third bit is set to "1" in this example. This is done via the multiplexers 1B and 18A. That is, the switching control section prepares the above data. The multiplexer is operated to send out the above bits together with the main signal from the output control unit 12 if the unit is in active use, and sends out only the above bits if it is in standby.

The demultiplexer 19.19A receives the signal of the above format from the time switch section 20, sends the main signal to the speed conversion section 17, and sends the fault information of the other package to the switching control section.

When the current package 10 is currently in use and the package IOA is in standby, and the failure detection units 16a and 16b of the current package 10 detect a failure, the switching control unit 14 sets the second bit to failure “1 n.”The time switch unit 20 , the main signal is sent to the connection destination package 30, and the fault information (the first
~4th bit) together with the signal sent from the connection destination package 30 (this also becomes the main signal), the package lO,
Send to 10A.

The demultiplexer 19A of the package IOA sends the first and second bits of the failure information to the switching control unit 14A. Upon receiving the first and second bits indicating whether the package IO is currently in use or has failed, the switching control unit 14A switches its own package IOA to the current status, operates the multiplexer 18A, and outputs the output (main signal) from the output control unit 12A. 3rd bit is currently used ゛'0
``'', the fourth bit is normal and sends failure information as ``0''. In the package IO, the demultiplexer 19 sends the third and fourth bits of fault information to the switching control unit 14, and in response to this, the switching control unit 14 indicates that its own system is on standby ゜'1゛failure''
1++, and only the failure information is sent without sending out the output of the output control unit 12.

In this way, the package 10 and IOA are switched between active and standby. The signal from the time switch section 20 is always sent to the package 10 and the IOA no matter where these packages are mounted, so it can simply be sent to the active/standby,
By simply setting the time slot for entering fault/normal information, switching signals can be reliably delivered and duplexing can be achieved.

When a failure is detected in the package 10, the switching control unit 14
9 10 may be set to immediately prohibit transmission of the main signal. If the faulty package 10 becomes normal after subsequent repair, it returns the second bit to "0" and waits for ゛'1゜'.
The first and second bits, which are normally "0", are sent out to prepare for a failure in the current package.

Note that the package 10 and IOA also perform format conversion and the like. Also, the terminal side interface IFP in Figure 5
3, IFP. The purpose of this is to share the processing of signals between TSWs and terminals.

The signal format of the synchronous terminal station is as shown in Figure 3(a).
And there is no frame sync bit. Frame synchronization is achieved using a separate signal, in this example an 8 KHz clock, as shown in FIG. 3(b).

Fig. 2 is a block diagram showing an embodiment of the present invention, Fig. 3 is an explanatory diagram of the signal format, Fig. 4 is an explanatory diagram of the duplex system, and Fig. 5 is a block diagram showing the configuration of the synchronous terminal station. , FIG. 6 is an explanatory diagram showing how packages are arranged on a shelf, and FIG. 7 is a block diagram showing a conventional example of redundancy.

Claims (1)

[Claims] 1. In the switching control method for the active and standby packages that are connected to the time switch unit to operate the interface and are duplicated to form a redundant system, the active package that detects a fault identifies the signal indicating the occurrence of the fault. The package is inserted into a time slot and sent to the time switch section, the time switch section sends it back to the standby package, and upon receiving this, the standby package replaces the current package and performs the operation of the current package. Switching control method for active and standby packages that make up a redundant system.