JPH05122748A - Master slave exchanging device - Google Patents

Abstract

PURPOSE:To automatically switch the action mode of an inter-PBX digital interface in an exchanging device when a line is abnormal. CONSTITUTION:In an exchanging device 1 in operation in a master mode, when a line abnormality detecting means 1a detects an abnormality 11 of a digital line 7, an action mode switching means 1c switches automatically the action mode of the self-exchanging device 1 to a slave mode. Together with it, through a mode switching signal sending and detecting means 1b to the exchanging device 2 during the action by a slave mode, an action mode switching signal is sent. When the exchanging device 2 detects the action mode switching signal through a mode switching signal sending and detecting means 2b, an action mode switching means 2c automatically switches the action mode of the self- exchanging device 2 to the master mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a master-slave exchange apparatus which is used in communication equipment and which operates in a master mode and a slave mode.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional switching equipment connection configuration through a digital interface between private branch exchanges (hereinafter referred to as PBXs). In FIG. 3, 14, 15, 1
6, 17 are communication terminals, 18, 19, digital lines, 2
Reference numeral 1 is a digital communication network, and each communication terminal 14-17
Is a switching device 12, a switching device 13, a digital line 1
The digital communication network 21 is connected via 8 and 19.

Further, the two exchange devices 12 and 13 are
They are connected via the PBX digital interface 20, the switching device 12 is in the master mode of the PBX digital interface 20, and the switching device 13 is the PB.
The X-to-X digital interface 20 is operating in the slave mode.

FIG. 4 shows a frame / multiframe structure of the PBX digital interface 20, and (Table 1) shows allocation of frame bits in a multiframe composed of 24 frames.

[0005]

[Table 1]

As is clear from this (Table 1), a multiframe is defined by a frame synchronization pattern (001011) formed by F bits for every four frames. The CRC bits e1 to e6 are used for error checking on the receiving side. On the receiving side, if F bits are fetched for each frame, m bits, CRC bits, m bits, and frame synchronization bits are fetched in order of 4 multiframe units.

In the communication path structure shown in FIG. 3, when the position 23 on the digital line 19 is out of synchronization and an abnormality such as a line disconnection occurs, the switching device 13 causes the line abnormality detecting means 13 to operate.
Abnormality is detected using a.

A line abnormality is detected and the digital communication network 21
The switching device 13, which has lost the communication path between the PBX and the PBX, secures a communication path via the PBX digital interface 20, the switching device 12, and the digital line 18. It is possible to make and receive calls to and from 21.

In this way, by using the PBX-to-PBX digital interface 20 even when the conventional exchange apparatus is used, another exchange apparatus connected through the PBX-to-PBX digital interface 20 even when an office line error occurs. It is possible to secure a communication route that goes through.

[0010]

However, in the above-described conventional switching apparatus, when an abnormality occurs in the central line of the switching apparatus operating in the master mode of the digital interface 20 between PBXs, for example, the digital line in FIG. If the synchronization is lost at the position 22 on the line 18 and an abnormality such as a line disconnection occurs, the switching device 12 operating in the master mode cannot establish network synchronization with the digital communication network 21. It cannot operate in master mode.

Therefore, the PBX-to-PBX digital interface 20 cannot be operated, and as a result, a communication path between the communication terminal 14 and the digital communication network 21, for example, cannot be secured.

Further, in order to avoid the above situation, it is necessary to artificially switch the switching device 12 to the slave mode and the switching device 13 to the master mode, and there is a problem that a quick countermeasure cannot be taken.

The present invention solves such a conventional problem, and automatically even when an abnormality occurs in the central line of the switching device operating in the master mode of the digital interface between PBXs. It is an object of the present invention to provide an excellent switching device that secures a communication path without stopping the operation of the digital interface between PBXs by switching the operation mode.

[0014]

In order to achieve the above object, the present invention comprises a line abnormality detecting means for detecting an abnormality in a digital line connected to a digital network in a switching device,
When the line abnormality detecting means detects an abnormality in the digital line network, an operation mode switching means for automatically switching the operation mode of the PBX digital interface is provided.
When the line abnormality detecting means in the exchange operating in the master mode of the BX digital interface detects an abnormality in the digital line, the operation mode switching means automatically switches the operation mode of the partner exchange. It is a thing.

[0015]

Therefore, according to the present invention, when the switching device operating as the master mode of the digital interface between PBXs detects a line abnormality, the operating mode of the partner switching device can be automatically switched and the communication path can be changed. This has the effect of being able to secure it and not having to perform mode switching by artificial work.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of an embodiment of the present invention. In FIG. 1, 1 and 2 are switching devices, 1a is a line abnormality detecting means provided in the switching device 1 for detecting an abnormality of the digital line 7, and 2a is provided in the switching device 2 and detects an abnormality of the digital line 8. It is a means for detecting line abnormality.

Further, 1b is a mode switching signal transmitting / detecting means provided in the exchange device 1, 2b is a mode switching signal transmitting / detecting means provided in the exchange device 2, and 1c is provided in the exchange device 1. The operation mode switching means 2c is an operation mode switching means provided in the exchange 2.

Further, 3, 4, 5, 6 are communication terminals, 10 is a digital communication network, and each of the communication terminals 3 and 4 is a digital communication network 10 via a switching device 1 and a digital line 7.
The communication terminals 5 and 6 are connected to the digital network 10 via the switching device 2 and the digital line 8.

The two switching devices 1 and 2 are connected via the PBX digital interface 9, the switching device 1 is in the master mode of the PBX digital interface 9, and the switching device 2 is the PBX digital interface 9. It is operating in slave mode. As this PBX digital interface 9, for example, an ISDN primary group interface (23B + D) is used.

Next, the operation of the above embodiment will be described with reference to FIG.
This will be described with reference to the operation flowcharts shown in (a) and (b). In FIG. 2A, the switching device 1 operating in the master mode determines whether or not there is an abnormality in the line (step S1), and if the line is operating normally, it is set in the slave mode. Repeating signal (0111111) is included in m bits for the operating switching device 2.
0) is sent (step S2) to notify the normal operation. Therefore, the signal pattern in m bits in the normal state is (01111111001111110 ...).

At the position 11 on the digital line 7 connecting the exchange 1 and the digital communication network 10, synchronization is lost,
Alternatively, when an abnormality such as line disconnection occurs, the switching apparatus 1 detects the abnormality using the line abnormality detecting means 1a, and the mode switching sending / detecting means 1b allows the switching apparatus 2 to detect the operation mode in m bits. A switching signal (00110011) is sent to notify the line abnormality, and the operation mode switching means 1c is used to switch the own operation mode to the slave mode (step S3). Therefore, the pattern of the operation mode switching signal in m bits is (001100110011).
0011 ...).

In FIG. 2B, the switching device 2 operating in the slave mode has a normal signal (011111).
When 10) is received (step S4), the slave mode is maintained as it is (step S5). The operation mode switching signal (00110) is passed through the mode switching signal detection means 2b.
When 011) is received (step S6), the operation mode switching means 2c is used to immediately switch the self-operation mode to the master mode (step S7).

Thus, according to the above embodiment, the PBX is
Even if an abnormality occurs in the digital line 7 in the office line of the exchange apparatus 1 operating in the master mode of the inter-digital interface 9, the exchange apparatus 1 operating in the slave mode is operated more than the exchange apparatus 1 operating in the master mode. 2 is notified of the operation mode switching signal, and each switching device 1, 2
Since the operation mode is automatically switched between the two, the communication path between the terminal and the network can be always secured without stopping the operation of the PBX digital interface 9.

Although the pattern of the operation mode switching signal is (00110011) in the above embodiment, other patterns may be used. Further, when three abnormal switching devices are used, this operation mode switching signal may include information on the switching device designated as the master mode.

[0025]

As is apparent from the above-described embodiment, the present invention allows the switching apparatus to automatically switch its own operation mode in accordance with an abnormal portion of the digital line, and to instruct the partner switching apparatus to switch the operation mode. Since the notification is sent, the PB is always used regardless of the abnormal part of the digital line.
Operates the digital interface between X and
It has an effect that a communication path between digital communication networks can be secured.

Further, there is also an effect that the conventional operation mode can be automatically switched.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a switching device according to a first embodiment of the present device.

FIG. 2 (a) is an operation flowchart of an exchange apparatus operating in a master mode, and (b) is an operation flowchart of an exchange apparatus operating in a slave mode.

FIG. 3 is a block diagram of a conventional exchange device.

FIG. 4 is a PB applied to the present invention and a conventional exchange device.
X and X digital interface frame and multi-frame configuration diagram

[Explanation of symbols]

 1, 2 Switching equipment 1a, 2a Line abnormality detecting means 1b, 2b Mode switching signal sending / detecting means 1c, 2c Operation mode switching means 3, 4, 5, 6 Communication terminal equipment 7, 8 Digital line 9 PBX digital interface 10 Digital communication network 11 Abnormal position of line

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04Q 3/58 101 9076-5K

Claims (1)

[Claims] 1. A switching device, which is connected to a digital network by a digital line and operates in a master mode as a main device that takes the initiative in line connection, and another device which operates in a slave mode as a slave device of the one switching device. An exchange device comprising an exchange device and exchange device connecting means for connecting the one exchange device and the other exchange device, wherein the one exchange device and the other exchange device are connected to the own device. A line abnormality detecting means for detecting an abnormality in the digital line; and an operation mode switching signal generated when the line abnormality is detected by the abnormality detecting means and an operation mode switching signal from a switching device other than the own device. When the operation mode switching signal is received from a switching device other than the own device via the mode switching signal sending / detecting means and the switching device connecting means The master-slave exchange apparatus having an operation mode switching means for switching the operation mode of automatically.