JPH05336114A - Network monitoring system - Google Patents

Abstract

PURPOSE:To early find out the abnormality of a line and a communication equipment by using a response monitoring time taking the line transmission state and the operating state of an equipment to be monitored into account in a network monitoring system monitoring the operating state of plural communication equipments constituting of a digital communication system by a supervisory and controlling device through the line. CONSTITUTION:The supervisory and controlling device 1 and the equipment 2 to be monitored are connected by a communication channel 3 for monitoring and controlling, the supervisory and controlling device 1 sends a command to the equipment 2 and when the device 1 does not receive a response from the equipment 2 within the prescribed monitoring time, it is decided that the equipment 2 or a communication channel 3 to the device is abnormal. When the device 1 sends a command to the equipment 2, the response time of the communication implemented with the equipment 2 so far is referenced and the decided monitoring time is set to a response monitoring timer 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network monitoring system in which a supervisory control device monitors operating states of a plurality of communication devices (monitored devices) constituting a digital communication system or the like through a line.

[0002] In recent years, with the enormous and complicated communication networks, there is a demand for higher reliability of the communication networks. For this reason, it is necessary to early detect and deal with failures in communication networks.

[0003]

2. Description of the Related Art FIG. 4 is a diagram showing a supervisory control system of a communication network to which the present invention is applied. In FIG. 4, a central control and monitoring device monitors and controls the operating states of a plurality of communication devices.

The supervisory control device 1 and a plurality of communication devices (monitored devices) 2 are connected by a supervisory control communication line 3, and the supervisory control device 1 requires periodic or supervisory control. At any time point, commands such as status inquiry and control are transmitted to the communication device (monitored device). The monitored device 2 decodes the command, performs a predetermined process, and then transmits a response corresponding to the command.

However, if a failure of the control / monitoring communication line 3 or a failure of the communication control unit of the monitored device 2 occurs, the response to the command transmitted from the monitoring device is not returned.

Therefore, a response monitoring timer in which the monitoring time (Tmax) unique to the system is set in the monitoring controller 1.
16 is provided, and the occurrence of a time-out in the monitoring timer 16 has been one of the factors for determining a failure in the communication device or the communication network.

That is, the monitor control device 1 activates the response monitor timer 16 when a monitor / control command is transmitted to the monitored device (counterpart device) 2, and within the monitor time Tmax set in the monitor timer 16. When the response from the monitored device is not returned, the monitoring timer 16 has timed out and it has been determined that the monitored device 2 or the communication line 3 leading to the monitored device 2 is in trouble.

The time until a response is received from the partner device in response to the transmitted command varies depending on the line route to the partner device, the state of the transmission path, the congestion state of the partner device, and so on. In order to detect only the true failure regardless of the above, the set time of the timeout is set to the maximum time Tmax that can absorb those fluctuations, and the same value is used for all the devices. Therefore, even with respect to the partner device having a short response time, the failure cannot be determined until the time Tmax has elapsed, and there is a problem that the speed of abnormality detection is impaired.

[0009]

In the above-mentioned prior art, there is a problem in that a failure cannot be detected until a time longer than the time when the response monitoring timer is set and the failure cannot be detected, and the response to the network failure is delayed.

The present invention has been made in view of the above problems, and by using a response monitoring time-out period in consideration of the transmission status of a line and the control device status,
It is an object of the present invention to enable early detection of an abnormality in a communication device.

[0011]

FIG. 1 is a block diagram showing the principle of a network monitoring system according to the present invention. As shown in FIG. 1, in the communication network in which the supervisory control device 1 and the monitored device 2 are connected by the supervisory control communication line 3, the supervisory control device 1 sends a command to the monitored device 2 as shown in FIG. If the response from the monitored device 2 to the command is not received within a predetermined monitoring time, the monitored device 2
Alternatively, in the network monitoring method that determines that the communication line 3 to the device is abnormal, when the monitoring device 1 transmits a command to the monitored device 2, The network monitoring system of the present invention is characterized in that the response monitoring timer 16 is set with the monitoring time determined by referring to the response time of the communication performed so far.

[0012]

[Operation] Response to the command of this time by referring to the response time in the communication that has changed depending on the device or the time transition due to the condition of the monitored device (delay of communication line, processing congestion in the monitored device, etc.) Since the response monitoring time can be set, the monitoring time can be shortened compared to the conventional technology in which the entire multiple monitored devices are monitored at the same fixed monitoring time, and line failures and monitored device failures can be prevented. It can be discovered early.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 2 is a diagram showing an embodiment of the method of the present invention, and FIG. 3 is a sequence diagram showing a monitoring time setting method.

In FIG. 2, reference numeral 1 is a supervisory controller.
Reference numeral 2 is a monitored device, and 3 is a communication line for monitoring control. The control and monitoring device 1 includes a command transmitting unit 11, a response receiving unit 12, an actual response time calculating unit 13, an actual response time storage unit 14 for the monitored device, a processing time table 15, a response monitoring timer 16, and a monitoring time setting unit. 17 are provided.

The processing time table 14 stores, for each command type, a standard processing time Te for performing processing based on the command received by the monitored device and returning a response.

The command transmission section 11 issues control / monitoring commands to each monitored device 2 periodically and randomly and sends them out. The response receiving unit 12 receives a response from each monitoring device 2.

As shown in FIGS. 2 and 3, the actual response time calculation unit 13 measures, every time a command is issued, the time T from when the command is issued until the response is received from the partner monitored device, and the content of the command is calculated. The corresponding standard processing time Te is read from the processing time table 15, the actual response time Tr is calculated by Tr = T-Te, and recorded in the actual response time storage unit 14 provided for the monitored device.
The actual response time Tr consists of a transmission delay time of the line to the partner monitored device, a processing waiting time depending on the load state of the monitored device, and the like, and is a value peculiar to the monitored device at that time. .

In this way, the control and monitoring device 1 stores the actual response real time Tr for the commands up to that time in the actual response time storage unit 13 for each monitored device. Next, when the control / monitoring device 1 attempts to issue the monitoring / control command of this time, the monitoring time setting unit 17 uses the actual response time Tr stored up to that time in the actual response time storage unit 14. The monitoring time Tadpt is determined by the following and set in the response monitoring timer 16.

Setting monitoring time Tadpt = selected actual response time Tk + standard processing time Te + margin time Ts As the selected actual response time Tk, the average value obtained by adding the actual response times Tr to the commands n times until then, the command of the immediately preceding time Actual response time T for one
Either r or the value updated to the maximum value by comparing the actual response times Tr up to that time each time is used.

As the standard processing time Te, the standard processing time Te corresponding to the content of the command to be issued this time is obtained from the processing time table 15. In this way, each time the command is sent for the monitoring time, the shortest monitoring time that can absorb the response delay due to the line route at that time and the operating status of the monitored device is set in the response monitoring timer 16.
It is possible to detect early that there is no response returned due to a failure of the line or the monitored device.

Prior to issuing the control / monitoring command, a sense command that directly obtains a response time T close to the actual response time Tr, which is the standard processing time of the partner device, is transmitted each time, The actual response time Tr may be directly obtained from the response time to the sense command, and the set monitoring time Tadpt may be determined based on the actual response time Tr. In this case, there is an advantage that it becomes more accurate because the delay time is required due to the operating state of the transmission path or the partner device immediately before the command is issued, but there is a disadvantage that the frequency of line use increases, and it is used properly according to the purpose.

[0022]

As is apparent from the above description, according to the network monitoring method of the present invention, the shortest monitoring time can be set according to the operating status of the partner monitored device and the characteristics of the transmission line, so that the failure detection time can be set. Is shortened, and the operation of the communication network is smoothly performed.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of a network monitoring method of the present invention.

FIG. 2 is a diagram showing an embodiment of the method of the present invention.

FIG. 3 is a sequence diagram showing a monitoring time setting method.

FIG. 4 is a diagram showing a supervisory control system of a communication network to which the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1-Control and monitoring device, 11 ... Command transmitting unit, 12 ... Command receiving unit, 13 ... Actual response time calculating unit, 14 ... Actual response time storage unit, 15 ... Processing time table, 16 ... Monitoring time setting unit, 17 ... Response Monitoring timer, 2 ... Monitored (communication)
Equipment, 3 ... Communication line for control and monitoring

Claims (2)

[Claims] 1. In a communication network in which the monitoring control device (1) and the monitored device (2) are connected by a monitoring control communication line (3), the monitoring control device (1) is connected to the monitored device 2 Command and the response from the monitored device (2) to the command is not received within the predetermined monitoring time, it is determined that the monitored device (2) or the communication line (3) to that device is abnormal. In the network monitoring method, when the monitoring device (1) sends a command to the monitored device (2), the monitoring is performed with the monitored device (2) each time. A network monitoring method characterized in that the monitoring time determined by referring to the communication response time is set in the response monitoring timer (16). 2. The monitoring device (1) sends a sense command for detecting a response delay from the monitored device immediately before transmitting a command to the monitored device (2), and sets a response time to the sense command. The network monitoring method according to claim 1, wherein the monitoring time is determined with reference to the monitoring time.