JP2737569B2 - Multiplexer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplexing apparatus for multiplexing and transmitting a plurality of data and voices through one high-speed digital line.

[0002]

2. Description of the Related Art FIG. 2 shows a configuration of a conventional multiplexer. In FIG. 2, reference numerals 11 and 12 denote multiplexing devices used in opposition, 13 a high-speed digital private line used as a normal operation line, and 14 a spare switching public line used when the high-speed digital private line 13 fails.

In the multiplexing apparatus 11, reference numeral 15 denotes a high-speed digital private line interface (I / F) accommodating the high-speed digital private line 13; I / F). Reference numeral 17 denotes a high-speed digital dedicated line state monitoring unit, 18 denotes a standby switching public line connection state monitoring unit, and 19 denotes a standby switching public line connection state monitoring unit 1.
8 is a communication path connection control unit that switches the communication path of the high-speed digital dedicated line I / F 15 and the standby switching public line I / F 16 according to the instruction of 8. Reference numeral 20 denotes an attribute setting unit that sets whether the multiplexing apparatus 11 is a master station or a slave station in the line switching, and 27 denotes an attribute holding unit that holds the contents set by the attribute setting unit 20 and an attribute for switching the slave station. Department.

In the multiplexing device 12, reference numeral 21 denotes a high-speed digital private line interface (I / F) accommodating the high-speed digital private line 13, and reference numeral 22 denotes a spare switching public line interface (A / C) accommodating the spare switching public line 14. I / F). Reference numeral 23 denotes a high-speed digital dedicated line state monitoring unit, and reference numeral 24 denotes a standby switching public line connection state monitoring unit. Reference numeral 25 denotes a high-speed digital dedicated line I / F 2 according to an instruction from the public line connection state monitoring unit 24 for standby switching.
1 and a call path connection control unit 26 for switching the call path of the standby switching public line I / F 22, and an attribute setting unit 26 for setting whether it is a master station or a slave station in the line switching. Reference numeral 28 denotes an attribute holding unit for switching between the master station and the slave station that holds the contents set by the attribute setting unit 26.

Next, the operation in the configuration of the conventional example will be described. In FIG. 2, the attribute holding units 27, 2 are previously set by the attribute setting units 20, 26 of the multiplexing devices 11, 12.
8 is set by the operation manager. For example, when the multiplexing device 11 is set as the master station and the multiplexing device 12 is set as the slave station, if a failure occurs in the high-speed digital dedicated line 13,
The information is transferred to the high-speed digital dedicated line interface 15 or the high-speed digital dedicated line interface 21, and the occurrence of this failure is detected by the high-speed digital dedicated line state monitoring unit 17 or the high-speed digital dedicated line state monitoring unit 23.

If this fault is detected by the high-speed digital leased line status monitoring unit 17 and it is determined that the fault is a serious fault that requires line switching, the high-speed digital leased line status monitoring unit 17 sets a spare switching public Line I / F
A call command is sent to the control unit 16, and the call command is ANDed with the output of the attribute holding unit 27. In this case, the multiplexing device 11 is set in advance as the main station, the call command is input to the standby switching public line I / F 16, and the standby switching public line I / F 16 is switched to the standby switching public line 14.
A switching line is configured with the standby switching public line I / F 22 through the switch. When the spare switching public line connection state monitoring unit 18 confirms that the switching line has been configured normally, the communication path connection control unit 19 switches the communication path. Similarly, when the protection switching public line connection state monitoring unit 24 confirms that the switching line is properly configured, the communication path connection control unit 25 switches the communication path, and the line switching ends.

On the other hand, if the failure is detected by the high-speed digital private line state monitoring unit 23 and it is determined that the failure is a serious failure that requires line switching, the high-speed digital private line state monitoring unit 23 A call command is transmitted to the public line I / F 22 for standby switching. This call command is ANDed with the output of the attribute holding unit 28. Here, the multiplexing device 12 is set as a slave station, and a call command is not input to the public line I / F 22 for standby switching. The fact that the failure of the leased line 13 is detected is notified to the high-speed digital leased line state monitoring unit 17 by alarm transfer to induce a switching operation.

As described above, even in the above-mentioned conventional multiplexer, it is possible to switch to the standby switching line when a failure occurs.

[0009]

However, in the above-mentioned conventional multiplexing apparatus, the occurrence of a failure not only in the direction from the slave station to the master station but also in the direction from the master station to the slave station is necessarily caused in the master station. There is a problem that it is necessary to recognize, and for that purpose, it is necessary to perform an alarm transfer process for detecting the latter obstacle.

Since the multiplexing device 11 is opposed to a plurality of multiplexing devices, a plurality of high-speed digital
3 and each dedicated line is individually provided with a spare switching public line 14, the attribute holding unit 27 is provided for each dedicated line.
Must be installed.

In this case, the multiplexing device 11 may face a plurality of multiplexing devices, and use a plurality of high-speed digital leased lines 13 to provide one spare switching public line 14 for all dedicated lines. Similarly, as a result, the control of the attribute setting becomes complicated, and the number of attribute holding units of the master station and the slave stations is required to be as large as the number of dedicated lines for accommodation.

The present invention solves such a conventional problem, making it unnecessary and easy to reduce the scale of processing for holding information and making complicated settings, and furthermore, simplifies the alarm system to increase the speed of normal operation lines. An object of the present invention is to provide an excellent multiplexing apparatus that can efficiently and accurately switch to a backup public line when a failure occurs in a digital leased line.

[0013]

In order to achieve the above object, a multiplexing apparatus according to the present invention includes a high-speed digital private line interface for accommodating a high-speed digital private line of a normal operational line, and a multiplexing device used when a normal operational line failure occurs. A standby switching public line interface accommodating the standby switching public line, a normal operating line status monitoring means for monitoring the status of the normal operating line, and sending a connection request to the standby switching line when a normal operating line failure occurs, A standby switching line connection control means for switching to a standby switching line, using the multiplexing device facing each other, and monitoring the state of the normal operation line with both state monitoring means, When the status monitoring means detects the occurrence of a fault, it is necessary to connect the standby switching line connection control means to the standby switching line on the side detected. And a structure for sending to a connection at a preset fixed time intervals do not overlap with each other to establish.

[0014]

With such a configuration, the multiplexing apparatus of the present invention monitors the state of the normal operation line by both of the state monitoring means when the multiplexing apparatus is used facing the multiplexing apparatus. When one or both of the status monitoring means detects the occurrence of a failure, the connection request to the standby switching line from the standby switching line connection control means on the detected side is connected at a preset constant time interval that does not overlap with each other. Until it is established,
Minimize request collisions when connection requests are sent from both parties.

In this case, since there is no relationship between the master station and the slave station, the setting of the master station and the slave station becomes unnecessary, and the processing scale of information holding can be reduced. Further, it is not necessary to perform complicated settings, and all the settings relating to the switching control are completed only by setting a management number that does not overlap in the network.

Further, since a connection request is sent from the multiplexing device that has detected the failure to the protection switching public line,
This eliminates the need to transfer the failure detection to the opposite station or recognize the failure detection at the opposite station. That is, a failure transfer function for always detecting a failure of the dedicated line at both stations can be deleted, and the alarm system can be simplified.

Therefore, when a failure occurs in the high-speed digital dedicated line of the normal operation line, the switching to the protection public line is performed efficiently and accurately.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a multiplexing apparatus according to the present invention.

FIG. 1 shows the configuration of the embodiment. In FIG. 1, reference numerals 31 and 32 denote multiplexing devices used oppositely.

In the multiplexer 31, reference numeral 33 denotes a high-speed digital dedicated line used as a normal operation line, reference numeral 34 denotes a spare switching public line used when a normal operation line fails.
Reference numeral 35 denotes a high-speed digital dedicated line interface (I / F) that accommodates the high-speed digital dedicated line 33.

Reference numeral 36 denotes a standby switching public line interface (I / O) for accommodating the standby switching public line 34.
F) and 37 are high-speed digital dedicated line status monitoring units, 38
Is a spare switching public line connection state monitoring unit, and 39 is a communication path switching unit.

Reference numeral 40 denotes an attribute setting unit for setting a device management number; 47, a device management number holding unit for holding the contents set by the attribute setting unit 40; 48, a retransmission time interval of a line connection request in the call control unit 49; ta is the device management number holding unit 4
A reproduction time generation unit determined from the number set to 7; 49
Is a call control unit for the high-speed digital private line I / F 34.

In the multiplexer 32, reference numeral 41 denotes a high-speed digital private line interface (I / F) accommodating the high-speed digital private line 33, and reference numeral 42 denotes a spare switching public line interface (A / B) accommodating the spare switching public line. (I / F), 43 is a high-speed digital exclusive line state monitoring unit, and 44 is a spare switching public line connection state monitoring unit.

Reference numeral 45 denotes a communication path switching unit; 46, an attribute setting unit for setting a device management number; and 50, a device management number holding unit for holding the contents set by the attribute setting unit 46. 5
1 is a reproduction time generator for determining the retransmission time interval tb of the line connection request in the call controller 52 from the number set in the device management number holding unit 50, and 52 is a call controller for the spare switching public line 34. is there.

Here, if the device management numbers of the multiplexing devices 31 and 32 are different, it is assumed that the time intervals generated by the reproduction time generating sections 48 and 51 are different.

Next, the operation of the configuration of this embodiment will be described. The operation manager sets the attribute setting units 40 and 46 in advance.
Thus, device management numbers that do not overlap each other in the network are set in the device management number holding units 47 and 50 respectively. After the setting of the device management number, if a failure occurs in the high-speed digital dedicated line 33, the information is transferred to the high-speed digital dedicated line I / F 35 or the high-speed digital dedicated line I / F 41, and the high-speed digital dedicated line status monitor 37 Alternatively, the high-speed digital private line state monitoring unit 43 detects this.

If the failure is detected by the high-speed digital private line state monitoring unit 37 and the failure is determined to be a serious failure requiring line switching, the high-speed digital private line state monitoring unit 37 sends the call to the call control unit 49. A call command is sent to the call control unit 49, whereby the call control unit 49 sets the reproduction time generation unit 48 to a backup at a retransmission time interval ta that does not overlap in the network generated from the management number stored in the device management number storage unit 47. A call request is sent to the switching public line I / F. As a result, the standby switching public line I / F 36 is switched through the standby switching public line 34 to the standby switching public line I / F 36.
/ F42 to form a switching line. When the standby public line connection state monitoring unit 38 confirms that the switching line has been configured normally, the communication channel switching unit 39 completes the switching of the communication channel based on the information. Similarly, the switching of the communication path is performed by the communication path switching unit 45, and the line switching is completed.

Next, if the high-speed digital private line state monitoring unit 43 detects a failure and determines that the failure is a serious failure that requires line switching, the high-speed digital private line state monitoring unit 43 performs call control. A call command is sent to the unit 52, so that the call control unit 52 determines that the reproduction time generation unit 51 has a retransmission time interval that does not overlap in the network generated from the management number stored in the device management number storage unit 50. At tb, a call request is sent to the protection switching public line I / F 42, and as a result, the protection switching public line I / F 42 is switched between the protection switching public line I / F 36 through the protection switching public line 34. Configure the line. When the standby switching public line connection state monitoring unit 44 confirms that the switching line has been normally configured, the information is used to switch the communication path between the high-speed digital dedicated line I / F 41 and the standby switching public line I / F 42. Is completed. Similarly, the switching of the communication path between the high-speed digital dedicated line I / F 35 and the standby switching public line I / F 36 is performed, and the line switching is completed.

A fault is detected by both the high-speed digital private line status monitor 37 and the high-speed digital private line status monitor 43, and the high-speed digital private line status monitor 37,
In both cases, when it is determined that the fault is a serious fault that requires line switching, the high-speed digital leased line state monitoring unit 37 sends a call command to the call control unit 49, and thereby the call control is performed. The unit 49 sends a call request through the spare switching public line I / F 36 at a non-overlapping retransmission time interval ta in the network generated by the reproduction time generation unit 48 from the management number held in the device management number holding unit 47. . Similarly, the high-speed digital leased line state monitoring unit 43 sends a call command to the call control unit 52, and the call control unit 52 causes the reproduction time generation unit 51 to execute the reproduction time generation unit 51.
Public switching I / F 42 for spare switching at retransmission time intervals tb that do not overlap in the network generated from the management number held at 0
Send outgoing call request. As a result, the protection switching public line I / F 42 forms a switching line with the protection switching public line I / F 36 through the protection switching public line 34. Then, when the spare switching public line connection state monitoring units 44 and 38 confirm that the switching line has been normally configured, the information on the communication path of the high-speed digital dedicated line I / F 41 and the spare switching public line I / F 42 is obtained based on the information. Is completed. Similarly, a high-speed digital private line I / F 35 and a standby public line I / F 35
The communication path is switched in F36, and the line switching is completed.

As described above, according to the above embodiment, by assigning a unique device management number to the multiplexing devices 31 and 32, when a failure occurs in the high-speed digital private line 33, both of the multiplexing devices 31 and 32 facing each other can be used. Since the line connection request can be sent from the multiplexing apparatus, there is no need for the multiplexers 31 and 32 to recognize the occurrence of a line failure in both transmission and reception.

Also, since the retransmission time intervals ta and tb do not overlap, even if the retransmission requests collide once, the retransmission requests from both parties immediately after the collision do not collide, and the line is re-arranged while the retransmission requests from both collide. A situation where switching cannot be performed can be avoided.

Further, according to the above embodiment, since there is no relationship between the master station and the slave station, there is no need to install a setting section for the master station and the slave station, the information holding section is simplified, and more complicated setting is performed. And the operability is improved.

[0033]

As is apparent from the above description, the multiplexing apparatus of the present invention monitors the state of the normal operation line by both of the above-mentioned state monitoring means when the multiplexing apparatus is used facing the multiplexing apparatus. . When one or both of the status monitoring means detects the occurrence of a failure, the connection request to the standby switching line from the standby switching line connection control means on the detected side is connected at a preset constant time interval that does not overlap with each other. Until the connection is established, minimizing the collision of requests when connection requests are sent from both parties, enabling efficient and accurate There is an effect that switching to the protection public line is performed.

That is, since there is no relationship between the master station and the slave station, the setting of the master station and the slave station becomes unnecessary, and the processing scale of information holding can be reduced. Further, there is an effect that it is not necessary to perform complicated settings, and that all the settings relating to the switching control are completed only by setting a management number that does not overlap in the network.

Further, since the multiplexer that detected the failure sends a connection request to the protection switching public line,
This eliminates the need to transfer the failure detection to the opposite station or recognize the failure detection at the opposite station. That is, it is possible to eliminate the failure transfer function for always detecting the failure of the leased line at both stations, which has the effect of simplifying the alarm system.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a multiplexing apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a conventional multiplexer.

[Explanation of symbols]

 31, 32 multiplexer 33 high-speed digital dedicated line 34 public line for spare switching 35, 41 high-speed digital dedicated line I / F 36, 42 public line I / F for spare switching 37, 43 high-speed digital dedicated line status monitoring unit 38, 44 Public line connection state monitoring unit for spare switching 39, 45 Communication line switching unit 40, 46 Attribute setting unit 47, 50 Device management number holding unit 48, 51 Playback time generation unit 49, 52 Call control unit

Claims (1)

(57) [Claims] A high-speed digital leased line interface accommodating a high-speed digital leased line of a normal operation line;
A standby switching public line interface that accommodates a standby switching public line used when a normal operating line failure occurs, a normal operating line status monitoring unit that monitors the status of the normal operating line, and a standby switching line when a normal operating line failure occurs Line connection control means for transmitting a connection request to the standby switching line, and switching to the standby switching line, using the multiplexing device in opposition, and monitoring the state of the normal operation line in both of the above-mentioned state monitoring means. In the case where one or both of the state monitoring means detects the occurrence of a failure, the connection request to the spare switching line from the spare switching line connection control means on the side detected is set to a predetermined constant value which does not overlap with each other. A multiplexing device for transmitting at a time interval until a connection is established.