JP2959940B2 - Network monitoring system - Google Patents

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 for monitoring a communication state of each signal line of a communication network such as an ISDN or a packet communication network.

[0002]

2. Description of the Related Art ISDN (Integrated Services Digital Network) and packet communication networks are communication systems for transmitting a large number of multiplexed data at high speed and efficiently. FIG. 11 is a block diagram showing a schematic configuration of such a communication system.

[0003] An ISDN signal line 2a connected to one ISDN exchange in a communication network 1 composed of a large number of ISDN exchanges and a large number of signal lines connecting the same is connected to a DSU (DSU) provided in a user's home. (Line terminating device) 3a. The DSU 3a is connected via a signal line to a TE1 (I
SDN standard terminal) 4 is connected.

[0004] The other ISDN signal line 2b is connected to a TE2 (I2) of a personal computer or the like via a DSU 3b and a TA (terminal adapter device) 5 similarly arranged in the user's house.
SDN non-standard terminal) 6.

Further, the ISDN in the communication network 1
A packet signal line 7 connected to the exchange is connected to a DTE (packet terminal) 9 through a DCE (data line terminating device) 8.
Connected to In some cases, the IS
A normal telephone terminal 10 is connected to a DN exchange via an analog telephone line 11.

In a communication system having such a configuration,
The interface between the ISDN exchange and each DSU 3a is constituted by a basic interface of [2B + D] or a primary rate interface such as [23B + D] or [24B].

The interface between the DSU 3a and the TE 14 and between the DSU 3b and the TA 5, that is, the interface at the S / T point is constituted by a basic interface or a primary rate interface.

Further, the interface between TA5 and TE26, that is, the interface at point R is, for example, RS-
232C (V.24 / V.28). The interface between the DCE 8 and the DTE 9, that is, the interface at the point DDX-P, 24 / V. 28, X. 21 / V. 11, V.
35 and the like.

[0009] In this way, at different points, when a new communication system having an individual interface configuration is constructed or during periodic inspection and maintenance, each IS
In the DN signal lines 2a and 2b and the packet signal line 7, a hardware failure such as a disconnection failure of the cable, a contact failure of the connector, or a connection abnormality between the exchange and the DSU or DCE is detected. Also, not only hardware obstacles,
It is necessary to detect a software failure such as a transmission error at an early stage and repair it.

Further, it is necessary to statistically evaluate the line quality such as a transmission error by measuring over a long period of time. Conventionally, when such a test is performed, the above-described S / T point. A signal measuring device is connected to each interface point such as R point, DDX-P point, etc., and the communication state of each point is monitored and displayed by a cathode ray tube or the like, and its signal waveform or digital value is analyzed to estimate an abnormal position. I was

[0011]

However, in the technique of installing the above-described signal measuring devices at each interface point in a user's home and observing a signal waveform or a measured digital value while a technician is resident, Not only is the task of loading and unloading each signal measuring device into and out of the user's house complicated, but also a technician must go to the user's house each time, which greatly increases the work load on the technician.

In addition, for an abnormal phenomenon that is constantly occurring, the abnormal phenomenon can be easily specified by a signal waveform or the like, and the cause of the abnormality can be investigated in a relatively short time. However, an abnormal phenomenon that occurs sporadically cannot be easily reproduced even by a technician who is familiar with this communication system, and it takes a lot of time and effort to identify the abnormal phenomenon and investigate the cause of the abnormality. .

In order to determine the cause of the abnormality, it is necessary to specify the position of the abnormality by comparing and comparing the communication state at each point on the communication line with respect to the same communication call originating from one terminal, for example. . However, even if the communication state at each interface point is measured by an individual signal measurement device, how many signal waveforms or data values measured by each signal measurement device correspond to each other is measured. Is complicated, and the time required to determine the cause of the abnormality further increases.

The present invention has been made in view of such circumstances, and by remotely operating a monitoring device provided at each interface point on a signal line and at a V point in an exchange by an external remote control device. It is possible to reduce the size of the monitoring device installed in the user's home, and to automatically collect communication information at each point on the signal line with a remote control device without having a technician resident at the user's home. It is an object of the present invention to provide a network monitoring system capable of investigating quality and cause of occurrence of an abnormality in a short time.

[0015]

In order to solve the above-mentioned problems, a network monitoring system according to the present invention comprises an S / T point, an R point and a DDX of each signal line of a communication network.
A plurality of terminal-side monitoring devices for detecting the communication state at point P and storing the detection result as monitor information and log information, and detecting the communication state at point V in the exchange in the communication network to determine the detection result as monitor information and An exchange-side monitoring device that stores as log information, and a remote control device that is connected to a signal line of a communication network, sends a transmission request to each monitoring device, and collects monitoring information and log information stored in each monitoring device. Have.

According to another aspect of the present invention, an abnormality analyzing means for judging an abnormal communication position on a communication network by comparing and comparing each remote control device with monitor information of each monitoring device for the same collected communication call. Is added.

[0017]

In the network monitoring system configured as described above, the terminal side monitoring device is connected to the S / T point, R point and DDX-P point of the signal line in each user's home of the communication network, and the switching equipment of the communication network is connected. Of the exchange-side monitoring device is connected to the V point inside. Then, for example, the remote control device is connected to a communication line drawn into the management center of the telephone company.

The point V in the exchange of the communication network indicates an interface point between the interface signaling device in the exchange and the subscriber line terminal equipment, and the exchange flowing through the signal line introduced into the user's home. Can be regarded as the output point within.

Each monitoring device detects the communication state at the S / T point, the R point, and the V point, and stores and holds the communication state as monitor information and log information. The monitor information and log information stored and held in each monitoring device are automatically transmitted to the remote control device in response to a transmission request from the remote control device.

Therefore, since it is not necessary to observe and analyze the waveform and data value of the signal state detected by the monitoring device provided in the user's house, the device itself can be made compact and lightweight. Also, there is no need for the technician to go to the user's home.

In another aspect of the invention, each remote control device not only collects monitor information and log information from each monitor device, but also compares and compares the monitor information of each monitor device for the same collected communication call. , A function of determining a communication abnormal position on a communication network is added.

That is, for example, a communication call originating from one terminal is transmitted to the user's premises via a signal line connected to a terminal of the communication destination via an exchange of the communication network. Existing V point. S / T point,
By monitoring the communication state at the point R, when a communication error occurs, the position where the error has occurred can be determined on the remote control device side.

[0023]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a communication system in which the network monitoring system according to the embodiment is incorporated. The same parts as those of the communication system shown in FIG. 11 are denoted by the same reference numerals.
Therefore, the detailed description of the overlapping part is omitted.

In the network monitoring system of this embodiment, an S / S between a DSU (line terminating device) 3b and a TA (terminal adapter device) 5 connected to an ISDN exchange in the communication network 1 via an ISDN signal line 2b. T
The terminal side monitoring device 12 is connected to a point and an R point between TA5 and TE2 (ISDN non-standard terminal) 6.

The DCE in the packet signal line 7
(Data line terminator) 8 and DTE (packet terminal) 9
Another terminal-side monitoring device 13 is connected to a point DDX-P between the terminals. This terminal side monitoring device 13 is connected to an ISDN exchange in the communication network 1 via the DSU 3c and the ISDN signal line 2c. Further, the terminal side monitoring device 13 is connected to an ISDN exchange in the communication network 1 via a modem 14a and a telephone line 11a.

Further, an exchange-side monitoring device 15 is connected to a point V in the ISDN exchange in the communication network 1. This exchange side monitoring device 15 is composed of DSU3d and ISD
ISD in communication network 1 via N signal line 2d
Connected to N exchange. Further, the exchange side monitoring device 15 is connected to the ISDN exchange in the communication network 1 via the modem 14b and the telephone line 11b.

Further, a DSU is connected to another ISDN signal line 2e connected to the ISDN exchange of the communication network 1.
The remote control device 16 is connected via 3e. The remote controller 16 is connected to an ISDN exchange in the communication network 1 via a modem 14c and a telephone line 11c. The remote control device 16 is provided, for example, in a management center of a telephone company.

FIG. 2 shows one IS in the communication network 1.
The above-described exchange-side monitoring device 15 in the DN exchange 17
It is a figure which shows the V point position to which is connected. The distribution module 18 is connected to the subscriber module 19 connected to the external ISDN signal line 2 and the external general telephone line 1.
1 is connected to the concentrator 20 connected. Further, in the subscriber system module 19, a signal device 22a for the basic interface and a signal device 22b for the primary group speed interface for incorporating information to be transmitted into a prescribed transmission format are connected to the communication path device 21.
Signals output from the basic interface signaling device 22a and the primary rate interface signaling device 22b are transmitted through the I-type subscriber line termination device 23a and the primary rate interface multiple subscriber line termination device 23b, respectively.
The signal is transmitted to the SDN signal line 2.

The basic interface signal device 2
V-points are respectively set between 2a and the I-type subscriber line terminal 23a, and between the primary rate interface signaling device 22b and the primary rate interface multiple subscriber line terminal 23b. Thus, the exchange-side monitoring device 15 detects the signal state at each V point.

FIG. 3 shows the S / T point, R point, DDX-P point, V
FIG. 3 is a block diagram showing a schematic configuration of terminal side monitoring devices 12 and 13 and a switching side monitoring device 15 for detecting a signal state of each interface point of the point.

As shown in FIG. 3, each of the monitoring devices 12, 13, and 15 is a monitoring device main body 24 that detects the communication state of the S / T point having the same configuration over all the monitoring devices 12, 13, and 15.
And each interface point (R point, DDX-P
(Point V, point V). Each adapter device 25 is detachably provided to an adapter terminal 25a of the monitoring device main body 24.

Therefore, when detecting the communication state at the S / T point, the terminal side monitoring device 12 is constituted using only the monitoring device main body 24, and when detecting the respective communication conditions at the S / T point and the R point, Monitoring device main body 24 and R-point adapter device 25
To configure the terminal-side monitoring device 12.

Further, when detecting the communication state of the DDX-P point, the terminal side monitoring apparatus 12 is constituted by using the monitoring apparatus main body 24 and the adapter apparatus 25 for the DDX-P point. Further, when detecting the communication state of the V point, the monitoring device main body 24
And the switch-side monitoring device 15 using the V-point adapter device 25.

Interfaces at the points R and DDX-P are RS-232C or V.264. Since these are similar serial interfaces such as 35, each adapter device 25 for the R point and the DDX-P point is composed of a simple circuit such as signal level adjustment and impedance adjustment. Therefore, DDX
The adapter device 25 for the point P uses the communication state at the point DDX-P as information equivalent to the communication state at the point R, and
Send to

Since the interface at point V is a basic interface or a primary group speed interface,
Close to point interface. Therefore, the adapter device 25 for the V point converts the communication state at the V point into information equivalent to the communication state at the T point, and sends the information to the monitoring device main body 24.

The monitoring device main body 24 is composed of a kind of information processing device such as a microcomputer. Then, as shown in FIG. 3, a control unit 27, a monitor unit 28, a log information detection unit 29, a trigger generation unit 30,
The communication unit 31 is connected. Further, a monitor information file 32 is connected to the monitor unit 28, and a log information file 33 is connected to the log information detection unit 29. The operation unit 34 is connected to the trigger generation circuit 30. In the monitor information file 32, an S / T point monitor information file and an R point monitor information file are formed.

Next, the operation of each section will be described in order. The monitor unit 28 monitors the communication state of the S / T point input from the signal connection terminals 35a and 35b connected to the S / T point of the ISDN signal line 2. Specifically, it monitors (a) layer 1 protocol information of the ISDN signal, (b) layer 2 and 3 protocol information on the D channel, and (c) layer 2 and 3 protocol information on the B channel.

When the communication state changes, the change time is written to each address of the S / T point monitor information file in the monitor information file 32 as S / T point monitor information in time series. When the monitor information is written to the last address of the S / T point monitor information file, the write address returns to the first address. That is, the S / T point monitor information file always stores the latest predetermined number of monitor information together with the generation time.

The monitor section 28 receives an input from the adapter device 25 connected to the adapter terminal 25a.
The monitor information of the communication state of each interface point to which the corresponding adapter device 25 is connected is written in the monitor information file 32 in time series.

For example, when the adapter device 25 is an R-point adapter device, that is, the terminal-side monitoring device 12 of FIG. 1, the input monitor information of the R-point is stored in the R-point monitor information in the monitor information file 32. The file is written in the same procedure as described above.

When the adapter device 25 is a DDX-P point adapter device, that is, the terminal side monitoring device 13 of FIG. 1, the input monitor information of the DDX-P point is stored in the monitor information file 32 at the R point. The information is written in the monitor information file in the same procedure as described above. In this case, since the signal connection terminals 35a and 35b are open, the monitor unit 28 does not monitor the communication state at the S / T point.

When the adapter device 25 is a V point adapter device, that is, the exchange side monitoring device 15 of FIG. 1, the input monitor information of the V point is stored in the S / T point monitor information in the monitor information file 32. The file is written in the same procedure as described above. In this case, the signal connection terminal 3
Since the terminals 5a and 35b are open, the monitor unit 28
Does not monitor the communication status at the / T point.

The log information detecting section 29 detects predetermined log information (event occurrence information) of the monitor information of the layers 1 and 2 detected by the monitor section 28 and stores the log information in the log information file 33. Register the number of occurrences.

That is, in the log information detecting section 29, as shown in FIGS. 4 to 7, log information to be detected is previously stored in a table format for each interface point (S / T point, R point). Is set.

For example, FIG. 4 shows a log information setting table 29a in which log information to be detected in layer 1 at the S / T point is set. The log information setting table 29a includes “normal noise detection”, “INF” in the direction from the terminal to the network (network) and in the direction from the network to the terminal.
A large number of abnormality detection items such as "out of synchronization" are set.

The log information setting table 29b shown in FIG.
In the table, each abnormality occurrence detection item of log information to be detected in the D channel of layer 2 at the S / T point is set. Similarly, each log information table 29c in FIG.
29d, B of layer 2 at the S / T point
Each abnormality occurrence detection item of log information to be detected in channel 1 and channel B2 is set.

Further, the log information setting table 29 shown in FIG.
In e, each abnormality occurrence detection item of the log information to be detected at the point R is set. Although not shown, an item for detecting the length of the information portion of the I frame is set as the log information of the point R.

The log information at point DDX-P is based on the log information at point R, and the log information at point V is at point T, that is, S / T.
Same as point log information. As shown in FIG. 8, an S / T point log information memory 33a and an R point log information memory 33b are formed in the log information file 33.

In the S / T point log information memory 33a, an area for counting the number of occurrences of the corresponding log information is formed for each of the layers 1 and 2 and for each generation direction of the log information. Therefore, when the same abnormality repeatedly occurs in a short period of time, the number of occurrences of the corresponding log information dramatically increases.

In the R-point log information memory 33b, there is formed an area for counting the number of occurrences of the corresponding log information for each generation direction of the log information at the R point. further,
A frequency table 33c of the length of the information portion of the I frame is formed in the R point log information memory 33b. That is, by looking at the frequency table 33c, it is possible to obtain statistical data of the length of the information portion of the I frame.

The log information detecting section 29 judges from the monitor information detected by the monitor section 28 whether or not each log information set in each of the log information setting tables 29a to 29e of FIGS. When log information is generated, the log information is updated by increasing the number of occurrences of the corresponding item in each of the log information memories 33a and 33b and the frequency table 33c shown in FIG.

Next, the trigger generator 30 will be described. This “trigger” means that the monitoring information file 32 is sent from each monitoring device 12.14.15 to the remote control device 16.
And a signal transmitted to prompt a request for transmission of monitor information and log information recorded in the log information file 33.

The trigger generation unit 30 (a) detects an important abnormality by the operator and performs a trigger output operation on the operation unit 34, and (b) a trigger terminal 30a from an external device (not shown). When a trigger command is input, the log information memory 33a. When the number of occurrences of the log information specified in 33b exceeds a preset threshold value, a trigger signal is transmitted to the remote control device 16 via the communication unit 31.

The communication section 31 is connected to an external telephone line 11 via a connection terminal 31a, and is also connected to a local processing terminal 31b. Further, the communication unit 31
Is the ISDN signal line 2 to be monitored via the switching unit 36.
b are connected to the signal connection terminals 35a and 35b. Further, the communication unit 31 transmits another ISDN through the switching unit 36.
I in the communication network 1 via the signal lines 2c and 2d
It is connected to the SDN exchange 17.

Then, the communication unit 31 controls the IS to be monitored.
A DN signal line 2b or a dedicated ISDN signal line 2c,
Various kinds of information exchange and data transfer are performed with the remote control device 16 via 2d, 2e or the telephone lines 11a, 11b, 11c. The operator selects and sets in advance which transmission path to use.

The control unit 27 determines the type of the connected adapter device 25, instructs the monitor unit 28, and in response to a transmission request from the remote control device 16 received via the communication unit 31, It has a function of transmitting the monitor information and the log information stored in the monitor information file 32 and the log information file 33 to the remote control device 16. further,
When a monitor stop command is input from the remote control device 16, the control unit 27 instructs the monitor unit 28 to issue a monitor stop command.

FIG. 9 is a schematic configuration diagram of the remote control device 16. The remote control device 16 is also formed of a kind of information processing device such as a personal computer. A control unit 41, a communication unit 42, a data collection unit 43,
A collected data writing unit 45 for writing collected data to a data file 44, an abnormality analyzing unit 46, a collecting condition setting unit 47,
The output unit 48 includes a printer and a CRT display device.

The communication unit 42 is connected to the IS via the connection terminal 42a.
It is connected to the DN signal line 2e and to the telephone line 11c via the connection terminal 42b. Further, it is connected to a connection terminal 42c having an RS-232C interface standard that can be connected to an external host computer or the like.

In the data file 44, as shown in FIG. 10, a monitor information collection file 44a for storing the monitor information transmitted from each of the monitoring devices 12, 13, 15
And a log information collection file 44b for storing log information transmitted from the monitoring devices 12, 13, and 15 as well.

The collection condition setting unit 47 is provided with, for example, a timing at which a man-machine device (not shown) sends a monitor information and log information transmission request to each of the monitoring devices 12, 13 and 15 instructed by an operator, 1
The amount of information to be transmitted among the information stored in the monitor information files 32, 13, and 15, and the log information to be transmitted among the information memories 33 a and 33 b of the log information file 33. Is set and stored.

As the transmission timing of the transmission request,
For example, it is a predetermined time of the day such as 24:00 at night. Also, if monitor information and log information are simultaneously transmitted from each of the monitoring devices 12, 13, and 15, conflict occurs on the signal line. Therefore, the transmission timings of transmission requests to be transmitted to each of the monitoring devices 12, 13, and 15 are not matched. It is shifted little by little.

When the control unit 41 receives a trigger signal from, for example, one monitoring device 12 via the communication unit 42, the control unit 41 sends a monitoring stop command of the communication state of the interface point to each of the monitoring devices 12 and 15, and At the same time, a transmission command for each information is transmitted.

The data collection unit 43 collects monitor information and log information from the monitoring devices 12 and 15 via the ISDN signal lines 2b, 2d and 2e. The collected data writing unit 45 writes the monitor information and log information of each of the monitoring devices 12 and 15 collected by the data collection unit 43 to the monitor information collection file 44a and the log information collection file 44b of the data file 44.

The abnormality analyzer 46 monitors the monitor information at each interface point, which is written in the monitor information file 44a based on the analysis request from the controller 41 and is detected by each of the monitoring devices 12 and 15 for the same communication call. From the communication network on the communication network.

That is, for example, a communication call originating from one terminal is transmitted to the ISDN exchange 17 of the communication network 1.
And the terminal (T) of the communication destination via the ISDN signal line 2b.
E2) is transmitted to point V existing on the transmission path,
By comparing and comparing the monitor information indicating the communication state such as the protocol information at the S / T point and the R point, the position where the communication abnormality has occurred is determined.

The output unit 48 displays the monitor information collected by the data collection unit 43 on a CRT display device or prints out the information by a printer. Further, the output unit 46 displays or prints out abnormal monitor information that can determine the abnormality occurrence position analyzed by the abnormality analysis unit 46.

Further, the output unit 4 has a function of translating protocol information (monitor information) represented by digital codes obtained at each interface point into a language that can be understood by the operator. Therefore, the operator can immediately understand the CRT display screen, the monitor information output to the printer, and the abnormal monitor information from which the abnormality occurrence position can be determined.

The output unit 48 displays the number of occurrences or the occurrence frequency of each log information item at each interface point collected in the log information collection file 44b in response to a display command from the control unit 41 in the form of a table or a graph. To display.

In the network monitoring system thus configured, the S / T point. Connect the terminal side monitoring device 12 to the point R,
The terminal side monitoring device 13 is connected to the point DX-P. And
The exchange-side monitoring device 15 is connected to a point V in the ISDN exchange 17 of the communication network 1. And each monitoring device 1
The communication networks 1 and 3 and 15 are connected by dedicated ISDN signal lines 2c and 2d or telephone lines 11a and 11b. Then, the remote control device 16 is installed in the management center.

The monitoring devices 12, 13, and 15 only detect and store the communication state of each interface point, and do not require a display device, a large-scale operation panel, or a keyboard. Therefore, the monitoring device itself can be manufactured small and lightweight, and the manufacturing cost can be greatly reduced. Therefore, it can be easily installed in the user's house.

Further, each of the monitoring devices 12, 13, 15
Monitor information and log information detected by the remote control device 1
6 automatically in response to a transmission request from the remote controller 16
Sent to. Further, when an abnormality occurs, the number of occurrences of the specific log information sharply increases and exceeds the threshold, and a trigger signal is automatically transmitted to the remote control device 16. Therefore, since the remote control device 16 can be left unattended, labor costs can be greatly reduced.

Further, a technician resident in the management center collects monitor information and log information at the same time by the monitoring devices 12, 13 and 15 by using the remote control device 16 and executes the CR.
It can be observed at the output unit 48 such as a T display device. Therefore, it is possible to grasp the protocol state at each point configuring the communication system without going to each user's house. The cause can be investigated in a short time when an abnormality occurs, and immediate measures can be taken. Further, the line quality of each communication line that needs to be evaluated based on statistics such as the number of occurrences of errors can be easily evaluated.

[0073]

As described above, in the network control system of the present invention, the S / T point, R
Monitoring devices provided at each interface point such as a point and a V point in the exchange are remotely controlled by an external remote control device. Therefore, it is possible to reduce the size of the monitoring device provided in the user's home, and to automatically collect communication information of each point on the signal line by the remote control device without having a technician resident at the user's home. Investigation of the signal quality and the cause when an abnormality occurs can be performed in a short time.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a communication system in which a network monitoring system according to one embodiment of the present invention is incorporated.

FIG. 2 is a block diagram showing an ISDN exchange of the communication system.

FIG. 3 is a block diagram illustrating a schematic configuration of a monitoring device of the network monitoring system according to the embodiment.

FIG. 4 is a diagram showing a log information setting table stored in a log information detection unit of the monitoring device.

FIG. 5 is a view showing a log information setting table similarly stored in the log information detection unit.

FIG. 6 is a diagram showing a log information setting table similarly stored in the log information detection unit.

FIG. 7 is a view showing a log information setting table similarly stored in the log information detection unit.

FIG. 8 is a view showing storage contents of a log information file of the monitoring device.

FIG. 9 is a block diagram showing a schematic configuration of a remote control device of the network monitoring system according to the embodiment.

FIG. 10 is an exemplary view showing storage contents of a data file of the remote control device.

FIG. 11 is a block diagram showing a configuration of a general communication system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Communication network, 2a-2e ... ISDN signal line, 3a, 3b, 3c, 3e ... DSU, 4 ... TE1,5
... TA, 6 ... TE2, 8 ... DCE, 12, 13 ... Terminal side monitoring device, 15 ... Exchange side monitoring device, 16 ... Remote control device, 17 ... ISDN exchange, 24 ... Monitoring device main body, 25
... Adapter device, 28 ... Monitor unit, 29 ... Log information detection unit, 30 ... Trigger generation unit, 31 ... Communication unit, 32 ... Monitor information file, 33 ... Log information file, 34 ... Operation unit, 43 ... Data collection unit 44 data file, 45
... Collection data writing unit, 46. Abnormality analysis unit, 47. Collection condition setting unit, 48. Output unit.

Continuing from the front page (72) Inventor Masaki Nishizawa 5-10-27 Minamiazabu, Minato-ku, Tokyo Anritsu Corporation (72) Inventor Soji Oshima 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Shigeo Suzuki 1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (56) References JP-A-5-199326 (JP, A) JP-A-5-292190 (JP, A) JP-A-6-261114 (JP, A) JP-A-3-49329 (JP, A) JP-A-5-167582 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) ) H04M 3/22

Claims (2)

(57) [Claims] 1. S / T of each signal line of a communication network
A plurality of terminal side monitoring devices (12, 13) for detecting the communication state of the point, the R point and the DDX-P and storing the detection results as monitor information and log information; Switch side monitoring device (15) that detects the communication state and stores the detection result as monitor information and log information
A remote control device connected to a signal line of the communication network, transmitting a transmission request to each of the monitoring devices, and collecting monitor information and log information stored in each of the monitoring devices (16)
And a network monitoring system. 2. The abnormality analyzing means (46), wherein the remote control device (16) determines a communication abnormality position on the communication network by comparing and checking monitor information of each monitoring device for the collected same communication call. The network monitoring system according to claim 1, further comprising: