JPH06177902A - Fault monitor for communication network system - Google Patents

Abstract

PURPOSE:To surely monitor a fault of a communication network in real time by providing a means monitoring a fault to a station of a LAN system and allowing the station to directly send an alarm signal through a private line on the occurrence of the fault. CONSTITUTION:On occurrence of a fault of a control section 20 in an alarm transmission circuit 31 built in a concerned monitor object station, a fault detection section 32 detects the fault and generates a detection output to activate a fault detection counter 33 and a fault watchdog timer 34. Furthermore, the detection section 32 resets a CPU in the control section 20 based on the fault detection to execute restoration processing. When the fault is a consecutive fault, the timer 34 detects it that the fault is the same consecutive fault and then the fault is discriminated to be a permanent fault. A comparator 37 compares a count of the counter 33 with a setting value set by a setting switch 36 and when the count reaches the setting reference count, the comparator 33 gives a fault detection output to alarm transmission circuits 38, 40 via a gate 46 to allow the circuits 38, 40 to raise an alarm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication network, for example, an optical loop LAN (local area network) system, and more particularly to a fault monitoring apparatus for a communication network system capable of surely detecting a fault. is there.

[0002]

2. Description of the Related Art A local area network (hereinafter referred to as LAN) which is one of communication network systems.
Is a communication network suitable for communication in a relatively narrow area such as a building unit or a factory unit, and is widely used in recent years as a network for connecting a plurality of independent devices to each other. It's coming.

This LAN is roughly classified into a bus type and a loop type. In the bus type LAN, a collision on the transmission line is detected by detecting the idle state of the transmission line by itself and starting transmission when it is idle. On the other hand, in a loop-type LAN, collision on the transmission path is avoided by the control of giving a usage right (or access right) to a transmission request.

A conventional loop type LAN is composed of, for example, an optical loop LAN device and a monitoring device for monitoring the same, and an alarm is sent out from this monitoring device when a failure occurs.

That is, as an example, as shown in FIG.
The N system 1 includes a plurality of stations (stations) 2a, 2b,
2c, ..., 2m are provided, and these are sequentially connected by a transmission path 7 in a ring shape so that information can be transmitted between stations.

A station is for connecting a host computer, a terminal device or the like, or for connecting a branch line LAN, and a packet having an address assigned to a terminal or the like connected to itself as a destination has been transmitted. In this case, in addition to the function of taking in this and sending out unrelated packets to the downstream side, sending of transmission packets from terminals etc. to the transmission path, monitoring of the transmission path, control of competition, etc. can be performed. These functions are the stations 2a, 2b, 2c,
It is realized under the control of the main control unit of 2 m.

These stations 2a, 2b, 2c, ...
Of the 2 m, one becomes a main station (for example, station 2 m in the figure), and this main station plays a central role in operating the LAN system. Reference numeral 5 is a bus-like branch line LAN.

A terminal device 6 is connected to the branch line LAN 5. Reference numeral 8 denotes a management device connected to the main station 2m, which has a keyboard, a display device, a printer, etc., and can exchange various commands and data with the LAN system. The management device 8 has a monitoring function for each station, and periodically issues a failure diagnosis response request for failure diagnosis by simultaneous broadcast,
When a response is received from each station, a failure diagnosis is performed based on the response, and if a failure is found, alarm information is displayed on an alarm display panel 9 provided for alarm display.

In such a configuration, in the communication between the terminals of each station, the transmission data from that terminal is packetized and sent from the station to which the terminal is connected to the transmission line of the LAN, and the data of the other terminal is transmitted. It is realized by the connected station receiving this packet and passing the data of this packet to the corresponding terminal.

On the other hand, the LAN is monitored by the main station 2 m
The management device 8 connected to the device periodically issues a failure diagnosis response request for failure diagnosis by simultaneous broadcast. This failure diagnosis response request is packetized and sent out simultaneously from the main station 2m to the LAN transmission line 7, and each station receives the failure diagnosis response request packet and responds in accordance with the request. LAN packets
To the transmission line 7 of. This response packet is received by the main station 2m and passed from the main station 2m to the management device 8. The management device 8 obtains a response from each station, performs a failure diagnosis based on the response, and if a failure is found, displays alarm information on an alarm display panel 9 provided for displaying an alarm.

As described above, conventionally, the failure diagnosis request is packetized and sent out to the transmission line by simultaneous broadcast, received at each station side and made to respond, and after waiting for this response, the state is judged and an alarm is issued in case of abnormality. I am trying to display it. The failure diagnosis request can be arbitrarily set within 10 to 120 minutes, and the request is generated and monitored at the set time interval. Therefore, conventionally, even if an abnormality occurs in a station or a transmission line of a LAN, it is not immediately known, and there is a concern that maintenance may be delayed and system operation may be seriously hindered.

Further, according to this system, the monitoring function is lost when a failure occurs in the management device itself.
Even if an abnormality occurs, it is not known at all, and the failure of the optical loop LAN separated from the loop due to the failure of the optical loop system is also unknown.

[0013]

As described above, conventionally, a management device having a failure monitoring function is used, this management device is connected to one station, and a failure diagnosis request is transmitted from the management device by simultaneous broadcast. It is sent to the road, received at each station and made a response, and after waiting for this response, the state is judged and an alarm is displayed in case of an abnormality. And
The failure diagnosis request generation interval is arbitrarily set between 10 minutes and 120 minutes, and the request is generated and monitored at the set time interval. Therefore, conventionally, even if an abnormality occurs in a station or a transmission line of a LAN, it is not immediately known, and there is a concern that maintenance may be delayed and system operation may be seriously hindered.

Further, according to this system, the monitoring function is lost when a failure occurs in the management device itself.
There is a problem that even if an abnormality occurs, it is not known at all, and there is also a problem that the failure of the optical loop LAN that is separated from the loop due to the failure of the optical loop system is not known. To solve this problem, connect the management device to each station respectively. The configuration causes a problem that the system costs too much.

The conventional monitoring is a method of diagnosing a failure according to how a response from each station responds to a failure diagnosing request, and there is no response or a response result even if there is a response. Since the failure is judged from the result such as something wrong, a rough alarm was issued.

Therefore, the object of the present invention is to
LAN system fault monitoring in real time, and
An object of the present invention is to provide a fault monitoring device for a communication network system, which can be reliably performed and can realize a monitoring function that can give an alarm at a low cost so that the user can also know what kind of failure is occurring and which has high reliability and maintainability. .

[0017]

In order to achieve the above object, the present invention is configured as follows. That is, a plurality of stations for connecting communication terminals and branch lines are connected by a transmission line, and communication is performed between the communication terminals through the stations. A failure detecting means for directly detecting a failure of the station, an alarm sending means that operates by a detection output of the failure detecting means to generate an alarm output, and an alarm output from the alarm sending means are independent dedicated lines. And an alarm display means for displaying an alarm.

[0018]

In the above structure, when a failure occurs in the station, the failure detecting means detects the failure and generates a detection output, whereby the alarm sending means generates an alarm output. This alarm signal is sent to the alarm display means via an independent dedicated line and is displayed on the alarm display means.

As described above, the failure detecting means provided in the station of the communication network system detects the failure, and when the failure is detected, the alarm signal can be directly sent to the alarm display means by the dedicated line. Therefore, at the same time as the occurrence of a failure, it is possible to know which station has a failure, and it is possible to take prompt action. Further, when a failure is continuously detected, it is possible to set it as a failure occurrence, and in this case, it is possible to prevent the failure alarm from ringing or being displayed due to a transient effect.
It is possible to prevent useless response by alarm display for a failure that does not continue. Since the failure is directly monitored, it is possible to distinguish the kind of failure.

Therefore, according to the present invention, it is possible to provide a reliable and maintainable local area network system capable of real-time and surely monitoring a failure of a LAN system and realizing a monitoring function at low cost. You can

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is a fault detecting means for detecting a fault in a main control system in a station, and a fault determination for determining whether the fault is a continuous fault or a transient fault and determining that a fault occurs when the fault is a continuous fault. Means and a fault detection means for detecting a fault of the power supply system in the station, and configured to drive the alarm sending means when a failure occurs in either the main control system or the power supply system, The alarm sending means is constituted by a non-voltage contact method and a tone sending method, and is sent to the alarm display means by a dedicated line and displayed. An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an optical loop L showing an embodiment of the present invention.
FIG. 2 is a block diagram of an alarm sending circuit in the AN device, and FIG. 2 is a block diagram showing a configuration of a LAN system using this alarm sending circuit.

In FIG. 2, 1 is a ring-shaped LAN system, 2a, 2b, 2c to 2m are stations (stations), 31 is an alarm sending circuit, and as shown in FIG. Stations 2a, 2b, 2
It is provided at c, ... 2 m. Reference numeral 5 is a branch line LAN, 6 is a terminal device, and 7 is a ring-shaped transmission path of the LAN system 1.

The LAN system 1 comprises a plurality of stations 2
2m are provided, and these are sequentially connected in a ring shape by the transmission path 7 so that information can be transmitted between the stations. A station is used to connect a host computer or terminal device, or to connect a branch line LAN. This is used when a packet whose destination is the address assigned to the terminal connected to itself is transmitted. In addition to the function of taking in and sending out unrelated packets to the downstream side, it is possible to perform transmission of transmission packets from terminals etc. to the transmission path, monitoring of the transmission path, control of competition, etc. These functions are the stations 2a, 2b,
It is realized under the control of the built-in main control unit of 2c, ..., 2m.

The alarm sending circuit 31 is provided for each station 2a,
2b, 2c, ... 2m, which are interface failures of terminals connected to the station to which they belong,
An abnormality of the main control unit, which is the center of control of the station,
When the power failure of the own station is monitored and an abnormality is detected, the information is sent to the outside as an alarm output, which is configured as shown in FIG.

In FIG. 1, 20 is each station 2
a, 2b, 2c, ... 2m are the main control units. The main controller 20 is composed of, for example, a CPU (processor), a memory, and the like. Reference numerals 32 to 46 are constituent elements of the alarm transmission circuit 31, and among these, 32 is a main control failure detection unit including, for example, a memory parity error detection circuit and a watch dog timer.
When an event related to an operation abnormality of the main control unit 20 is detected, such as a data parity error occurring due to the operation of the main control unit 20 or a watch dog timer timing out, the main control system is detected. A fault detection signal is generated. Further, the main control system failure detection unit 32 resets the CPU in the main control unit 20 by the failure detection,
It has a function to perform recovery processing.

Reference numeral 33 is a fault detection counter for counting the number of fault occurrences, which counts when it receives a main control system fault detection signal output from the main control fault detection unit 32.

Reference numeral 34 denotes a fault monitoring timer for determining whether or not the continuous fault is a transient fault, and when receiving a main control system fault detection signal from the main control fault detection unit 32, starts a time counting operation, The gate control signal is generated at the stage when the main control system failure detection signal for the reference determination number is received before the predetermined time elapses. The failure monitoring timer 34 is reset when the main control system failure detection signal is not received for the reference number of determinations before the elapse of a predetermined time.

Reference numeral 35 indicates how many times the same failure occurs and is determined to be a failure (that is, how much the failure is monitored).
A determination count setting switch for setting the determination count, which gives the set determination count to the failure monitoring timer 34.

Reference numeral 36 is a setting switch for setting a reference value for how many times the same failure occurs to determine a failure, and the set reference value is given to the comparator 37.
The comparator 37 is a comparator for comparing the count value of the failure detection counter 33 and the value of the judgment number setting switch 35, and the comparator 37 of the failure detection counter 33 is based on the judgment number value set in the judgment number setting switch 35. When the count values are compared and the count value reaches the reference value, a main control system abnormality detection output is generated.

Reference numeral 46 denotes a gate, which is a fault monitoring timer 34.
The gate control signal output from the comparator 37 opens the gate to pass the main control system abnormality detection output from the comparator 37.
When there is no gate control signal, the gate is closed and the comparator 37
The main control system abnormality detection output from is blocked.

Reference numeral 38 is a non-voltage contact type alarm sending circuit, which is composed of a main control failure relay 39 and a power failure relay 45. Of these, the main control failure relay 39 is a relay that operates when a main control system failure occurs, and the power supply failure relay 45 is a relay that operates and closes the contacts when a power supply failure occurs. That is, the main control failure relay 39 is connected to the gate 4
6 is activated by the main control system abnormality detection output from the comparator 37, and the power supply failure relay 45 is activated by receiving the power system failure detection output of the power system failure detection unit 44. 39a is a relay contact of the main control fault relay 39, 4
5b is a relay contact of the power failure relay 45.

Reference numeral 40 is a tone sending type alarm sending circuit, which is composed of a tone generating section 41, a level adjusting section 42, and a matching transformer 43. Tone generator 41
Operates when it receives the main control system abnormality detection output from the comparator 37 or the power supply system fault detection output of the power supply system fault detection unit 44 which is given through the gate 46. A different predetermined tone signal is generated depending on whether the system fault detection output is output. That is, the tone generator 41 is composed of, for example, a tone generator, and generates different tones depending on the fault of the main control system and the fault of the power supply system.

The level adjusting unit 42 adjusts the transmission level of the tone signal generated by the tone generating unit 41.
The matching transformer 43 is a transformer for performing matching when the tone signal adjusted by the level adjusting unit 42 is sent to the dedicated line. Reference numeral 44 is a power supply system failure detection unit for detecting a power supply system failure, and when the power supply to the station to be monitored by itself is cut off,
The power supply system fault detection output is generated. The power failure relay 45, which operates when a power failure occurs, is configured to be activated upon receiving a failure detection output from the power failure detection unit 44.

The operation of the present apparatus having such a configuration will be described. The main control system failure detection unit 32 of the alarm transmission circuit 31 is composed of a memory / parity / error detection circuit, a watch dog timer, etc., and when a failure occurs in the main control unit 20 built into the monitored station of its own. The main control system failure detection unit 32 is reset by the memory parity error detection circuit and the watch dog timer function (when the main control unit 20 is operating normally, it is reset periodically, and even if a predetermined time elapses). If it is not reset, an alarm is generated to monitor the operation abnormality) and the fault is detected and a detection output is generated. Then, with this detection output of the main control system failure detection unit 32, the failure detection counter 33 is operated and the failure monitoring timer 34 is started. Further, the main control system failure detection unit 32 detects the failure and detects the C in the main control unit 20.
PU is reset and recovery processing is performed.

Here, if the generated fault is not a one-time fault but a continuous fault, the main control system fault detection unit 32 will detect the fault again, and the fault detection counter 33 will be detected by the detected output. Advances one count.

In this way, if there is a continuous failure,
While the fault monitoring timer 34 is operating, the same fault is detected several times, and since it continues, it can be determined that the fault is complete.

That is, the main control system failure detection unit 32 resets the main control unit 20 and generates a failure detection output each time a failure is detected, and the failure detection counter 33 increments by one each time. At the same time, the failure detection output from the main control system failure detection unit 32 is counted for a predetermined time from the time when the failure monitoring timer 34 receives the first failure detection output, and this count value is set to the determination number setting switch 35.
Compared with the number of judgments given from, if the number of judgments is reached, a gate control signal is output. Since this gate control signal is given to the gate 46, the gate 4
6 is opened.

On the other hand, the comparator 37 is the fault detection counter 33.
Is compared with the set value of the setting switch 36 as a reference, and when the count value reaches the reference value, an abnormality detection output is generated and given to the gate 46. Therefore, this abnormality detection output is given to the alarm output circuit 38 and the alarm output circuit 40 through the gate 46.

If the failure detection output from the main control system failure detection unit 32 does not reach the number of judgments given from the judgment number setting switch 35 before the failure monitoring timer 34 times out, the failure monitoring timer 34. Does not generate a gate control signal, the gate 46 is not opened, and therefore, even if the comparator 37 outputs an abnormality detection output, it does not pass through. This results in complete failure (continuous failure)
Can be determined by distinguishing erroneous detections due to a continuous failure that does not continue or noise or the like.

The monitoring time of the failure monitoring timer 34 is, for example, a monitoring time setting switch 35 composed of a switch group.
Can be set to any value within a certain range. Further, in order to determine how many times the same fault occurs as a fault, for example, an arbitrary value within a certain range is set by a decision count setting switch 36 formed of a switch group, and this value is set. And the value of the failure detection counter 33 are compared by the comparator 37 to make a determination.

When it is determined that there is a failure by the above processing,
The main control fault relay 39 and the tone output type alarm output circuit 40 in the voltageless contact type alarm output circuit 38 are simultaneously driven and output to the outside as an alarm signal. That is,
The comparator 37 produces an output when the count value reaches the reference value, which is given to the gate 46 as an abnormality detection output. On the other hand, the fault monitoring timer 34

The tone generation section 41 of the tone transmission type alarm transmission circuit 40 is composed of, for example, a tone generator, and generates different tones depending on the fault of the main control system and the fault of the power supply system. The generated tone is sent to the dedicated line via the matching transformer 43 after the sending level is adjusted by the level adjusting unit 42.

Next, regarding the failure of the power supply system, the power supply system failure detection unit 44 monitors the power supply of the station to be monitored by itself, and when the power failure is detected, the power supply failure detection signal is generated and the power of the alarm sending circuit 38 is supplied. It is sent to the fault relay 45 and the tone generator 41 of the alarm output circuit 40. This excites the power failure relay 45 and closes its relay contact 45a,
Further, the tone generator 41 is driven to generate a tone signal. This tone signal is level-adjusted by the level adjusting unit 42 and is sent to the dedicated line via the matching transformer 43.

In this way, even when the power supply system failure occurs, the power supply failure relay 45 and the tone sending method alarm sending circuit 40 in the voltageless contact type alarm sending circuit 38 are driven, as in the main control system failure. An alarm output operation by a non-voltage contact and an alarm output operation by a tone signal are performed.

In this way, the alarms can be monitored by the alarm sending circuit 31 in each station, but in this system, as shown in FIG. 3, an alarm display panel 9 is provided for each alarm sending circuit 31. To display an alarm, or as shown in FIG. 4, an alarm display panel 9 is provided in the central monitoring center, and the alarm output of each alarm transmission circuit 31 is guided to the alarm display panel 9 of this monitoring center. It becomes possible to say that it is displayed here. Of course, in FIG. 3, the alarm display panel 9 provided for each alarm transmission circuit 31 may be arranged at the central monitoring center or in the vicinity of each station.

In this system, when the alarm display panel 9 is near the alarm transmission circuit 31, an alarm is displayed by using the contact signals of the relays 39 and 45 of the alarm transmission circuit 38,
When the alarm display panel 9 is far from the alarm transmission circuit 31, the alarm display is performed by using the alarm signal by the tone signal of the alarm transmission circuit 40 of the tone transmission system. This is because the line resistance does not pose a problem in the case of a short distance, so it is possible to use the contacts of the relays 39 and 45, which are simple in circuit configuration on the alarm display panel 9 side, as a signal and display an alarm. The circuit configuration on the side of the alarm display panel 9 becomes a little complicated because the resistance of the line becomes a problem if the distance is far, but a tone signal that can send an alarm to a distant place is used. Since the tone signal is different between the power supply system and the main control system, it is possible to distinguish and display an alarm even if any system failure occurs.

As described above, the present apparatus is provided in a station, and a failure detecting means for detecting a failure of the main control system of the station, and a main control system when the failure detecting means detects the failure a predetermined number of times within a predetermined time. An abnormality determination means for generating an abnormality detection output, a power supply failure detection means for monitoring the power supply of the station and generating a failure detection output when an abnormality occurs in the power supply, and a switch which is opened / closed in response to the main control system abnormality detection output. And a switch that opens and closes in response to the fault detection output, and uses the non-voltage contact type alarm transmission means for notifying failure information by opening and closing the non-voltage contact, and the main control system abnormality detection output and fault detection output as inputs. , A tone signal generating means for generating different tone signals corresponding to each, and a main control system of a station to be monitored and When the power supply is monitored and the main control system continues to be abnormal, and when the power supply system has an abnormal power supply, a fault detection output is generated for each, and it differs depending on whether the main control system is abnormal or the power supply system is abnormal. Generates a tone signal, opens and closes the contacts for each system of the main control system / power supply system to generate an alarm output, and displays the alarm output (tone signal or contact signal) on a dedicated line. Since it is sent to the panel and the alarm display or alarm sounds, it becomes possible to immediately detect the failure of the main control system / power supply system of the monitored station and notify it to the outside, and the alarm output is a tone. Since it is output as a signal and contact output, contact output is sufficient for short-distance alarm display panels, and a tone signal can be used for long-distance alarm display panels. , Also, so that can be installed even in remote locations.

In this way, the state of the station is directly
By monitoring and detecting the failure of the main control system / power supply system and outputting the alarm to the line dedicated to the alarm, the failure of the monitoring device to be monitored from the center of the LAN system as in the past,
The situation that the failure can be monitored due to the failure of the transmission line of the LAN is solved, and unlike the conventional method of monitoring the failure at a predetermined time interval, the failure is immediately detected when it occurs. An alarm can be issued and maintenance can be performed quickly.

Further, since an alarm can be issued for each failure, it is possible to immediately know what kind of failure has occurred, and it is possible to take an appropriate action and to realize it with a relatively simple structure. The cost increase of the system can be suppressed.

Therefore, the failure of the LAN can be monitored in real time and reliably, and a monitoring function that can give an alarm at a low cost and to know what kind of failure is realized can be realized. It is possible to obtain a fault monitoring device for a good communication network system. The present invention is not limited to the embodiments described above and shown in the drawings, but can be appropriately modified and implemented within the scope of the invention.

[0052]

As described above, the station of the LAN system is provided with means for monitoring a failure, and when a failure occurs, an alarm signal can be sent directly from the station via a dedicated line. It is possible to know whether a station has a fault and take quick action. Also, since it is possible to prevent the fault alarm from ringing due to transient effects, it is possible to prevent wasteful response due to the alarm ringing. , A reliable and maintainable communication network that can perform real-time and reliable fault monitoring of LAN, and can also provide a monitoring function that can give an alarm at low cost to let you know what kind of failure it is. A system failure monitor can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an alarm transmission circuit according to the present invention.

FIG. 2 is a LAN incorporating an alarm transmission circuit according to the present invention.
The system block diagram which shows the structural example of a system.

FIG. 3 is a system block diagram showing a configuration example of a LAN system according to the present invention including an alarm display panel.

FIG. 4 is a system block diagram showing a configuration example of a LAN system including an alarm display panel according to the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional system.

[Explanation of symbols]

1 ... LAN system 2a-2m ...
Station 7 ... Transmission path 8 ... Management device 9 ... Alarm display panel 20 ... Main control unit 31 ... Alarm transmission circuit 32 ... Main control system fault detection unit 33 ... Fault detection counter 34 ... Fault monitoring timer 35 ... Judgment number setting switch 36 ... Setting switch 37 ... Comparator 38 ... Alarm sending circuit of non-voltage contact system 39 ... Main control failure relay 39a that operates when main control system failure occurs ... Relay contact of main control failure relay 39 ... Alarm sending circuit of tone sending method 41 ... Tone generating section 42 ... Level adjusting section 43 ... Matching transformer 44 ... Power system failure detecting section 45 ... Power failure relay 45b that operates when power failure occurs 45b ... Relay contact 46 of power failure relay 45 ... Gate.

Claims (4)

[Claims] 1. An apparatus for fault monitoring used in a communication network system in which a plurality of stations for connecting communication terminals and branch lines are connected by a transmission line, and communication between communication terminals is performed through the stations. Fault detection means provided in the station for directly detecting a fault of the station, alarm sending means for operating by the detection output of the fault detecting means to generate a warning output, and warning output from the warning sending means are independent. A fault monitoring device for a communication network system, comprising: an alarm display unit for receiving an alarm and displaying an alarm on a dedicated line. 2. The fault monitoring apparatus for a communication network system according to claim 1, wherein the alarm output of the alarm sending means uses a contact of a non-voltage contact. 3. The fault monitoring device for a communication network system according to claim 1, wherein the alarm output of the alarm sending means is a tone signal. 4. The fault monitoring apparatus for a communication network system according to claim 1, wherein the fault detecting means has a function of outputting a detection signal when a fault is continuously detected for a predetermined time.