JP2001069243A - Subscriber transmitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably execute a subscriber test in an ISDN line in a short time. SOLUTION: The object specifying means 3a of this subscriber transmitting device 3 specifies an network terminating device to be a test object. An in- communication detecting means 3b decides whether the network terminating device specified by the means 3a is in the middle of communication at that time and notifies it to a testing means 3c. The means 3a executes a test about the electric characteristic and other characteristics of a subscriber line between the network terminating device specified by the means 3a and itself when the means 3b detects that the network terminating device is not in the middle of communication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a subscriber transmission device, and more particularly, to a subscriber transmission device disposed between an exchange and a network terminating device for relaying information between them based on a predetermined protocol.

[0002]

2. Description of the Related Art In recent years, with the spread of the Internet,
For example, ISDN (Integrated Service Digital Network)
rk) -BRA (Basic Rate Access) and the like are spreading to ordinary households.

[0003] In such an ISDN-BRA, if any communication failure occurs, a PSTN (Public Swithced Telephone) is used in order to identify the failure site.
As in the case of Network), it is necessary to perform a subscriber test to determine the quality of a subscriber line or the like.

[0004]

However, ISDN-
Since a subscriber test method for BRA has not been established at this time, a failure occurrence site is specified by measuring the electrical characteristics of the subscriber line as in the case of PSTN.

However, the ISDN-BRA has a problem that the line condition is different due to the connection of the network terminating equipment to the subscriber's house, and it is difficult to use the same method as the PSTN as it is. .

Further, it is conceivable to identify a faulty site by measuring an error generated in a subscriber line or the like by using a measuring device. Therefore, there is a problem that it is troublesome, and since such a complicated operation needs to be performed, a great amount of time is required until recovery.

Further, in the case of PSTN, since the line is controlled by a signal indicating that the loop has been opened or closed, it is relatively easy to detect whether or not a call is in progress. But ISDN-BR
In the case of A, the communication state cannot be easily known because it is necessary to decode the contents of the message when determining whether or not communication is being performed. Therefore, there is also a problem that if the test is executed ignoring this, communication is interrupted.

The present invention has been made in view of the above points, and has as its object to provide a subscriber transmission apparatus capable of performing a subscriber test such as ISDN-BRA.

[0009]

According to the present invention, in order to solve the above-mentioned problems, the exchange 4 and the network terminators 2a to 2 shown in FIG.
In a subscriber transmission device 3 that is disposed between 2c and relays information between them based on a predetermined protocol, target specifying means 3a for specifying a predetermined network termination device to be tested; The communication detecting means 3b for detecting whether the predetermined network terminating device specified by the means 3a is communicating, and the object specifying means 3a specified according to the detection result of the communication detecting means 3b. Test means 3c for testing characteristics relating to a communication state with the network terminating device.

Here, the target specifying means 3a specifies a predetermined network termination device to be tested. Communication detection means 3
b detects whether or not the predetermined network terminating device specified by the target specifying means 3a is communicating. Test means 3c
Tests the characteristic of the communication state with the network terminating device specified by the target specifying unit 3a according to the detection result of the communication detecting unit 3b.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a principle diagram for explaining the operation principle of the present invention. In this figure, subscriber terminals 1a to 1a
1c is composed of, for example, a telephone or a modem, converts an original signal such as a voice signal into a digital signal and supplies the digital signal to the network terminating devices 2a to 2c, and the digital signal supplied from the network terminating devices 2a to 2c. The signal is converted into a corresponding original signal and output.

The network terminating devices 2a to 2c are adapters for exchanging information with the subscriber transmission device 3 by digital signals. The subscriber transmission device 3 is an adapter that is installed to face the plurality of network terminating devices 2a to 2c and exchanges information with the network terminating devices 2a to 2c by digital signals.

Here, the subscriber transmission device 3 comprises an object specifying means 3a, a communication detecting means 3b, and a testing means 3c. The target specifying unit 3a specifies a predetermined network termination device to be tested.

The in-communication detecting means 3b includes an object specifying means 3a
It is detected whether or not the predetermined network terminating device specified by the above is communicating at that time. If the network terminating device specified by the target specifying unit 3a is not communicating at that time, the test unit 3c performs a test on the target network terminating device and the subscriber line.

In the subscriber transmission device 3 shown in FIG. 1, only parts related to the present invention are shown, and other parts are omitted. The exchange 4 performs a process of closing a line with a desired communication partner.

Next, the operation of the above embodiment will be described. Now, assuming that a telephone number or the like relating to the network termination device to be tested is input to the subscriber transmission device 3,
The target specifying unit 3a specifies a corresponding network terminating device with reference to, for example, a database.

The database has an independent configuration (external device), and information such as the ID of the network terminating device corresponding to the telephone number is searched in this external database.
May be specified by the target specifying unit 3a.

When the target network terminating device is specified, the in-communication detecting means 3b determines whether or not the target network terminating device is communicating. For example, if the network terminating device 2a is specified as a test target by the target specifying unit 3a, the in-communication detecting unit 3b refers to a message exchanged with the network terminating device 2a and is communicating. It is determined whether or not this is the case, and the test means 3c is notified.

Next, when the target network terminating device is not communicating, the test means 3c tests the electrical characteristics of the subscriber line connecting the network terminating device and the subscriber transmission device 3. At the same time, a data loopback is executed for a subscriber circuit (not shown) built in the subscriber transmission device 3 or a target network terminating device, and an error occurrence rate is measured. Then, by referring to these measurement results, it is possible to specify the location where the failure has occurred.

In the present example, since the network termination device 2a is the object of the test, the subscriber transmission device 3 firstly sets the electrical characteristics of the subscriber line with the network termination device 2a (for example,
Electrical resistance, capacitance, voltage, etc.).

Subsequently, the subscriber transmission device 3 requests the network termination device 2a to loop back transmission data,
Transmit data having a predetermined pattern. Then, by inspecting the looped-back data, the error occurrence rate between the subscriber transmission device 3 and the network termination device 2a is detected.

Next, the subscriber transmission device 3 requests the built-in subscriber circuit to perform loopback, and then supplies data having a predetermined pattern. Then, by inspecting the looped-back data, the internal error rate of the subscriber transmission device 3 is detected.

Finally, the subscriber transmission device 3 estimates the location of the failure by integrating the information obtained as a result of the test, and outputs it to a display device (not shown). As described above, according to the subscriber transmission device 3 according to the present invention,
After identifying the test target and determining whether or not the target is communicating, various tests are performed to estimate the location of the failure, thereby hindering the communication of the target subscriber. The test can be performed without the need for a test.

Further, not only can the labor for connecting the measuring instruments be omitted, but also a series of processes are automatically executed, so that the burden on the person who performs the test can be reduced.

Next, a configuration example of the embodiment of the present invention will be described. FIG. 2 is a diagram illustrating a configuration example of the embodiment of the present invention. In this figure, subscriber terminals 10a to 10a
c is composed of, for example, a telephone, a modem, a facsimile, etc., converts an original signal such as a voice signal or an image signal into a digital signal and supplies the digital signal to the network terminating devices 20a to 20c. Is converted into a corresponding original signal and output.

The network terminating devices 20a to 20c are adapters for exchanging information with the subscriber transmission device 30 by digital signals via the subscriber lines 25a to 25c, respectively.

FIG. 3 is a diagram showing a configuration example of the network termination device 20. In this figure, only the portion according to the present invention is shown. In this figure, when information for requesting loopback is transmitted from the subscriber transmission device 30, the detection unit 21 detects this. As information for requesting loopback, a predetermined bit of a packet transmitted by the subscriber transmission device 30 can be used.

When the detecting unit 21 detects the information requesting the loopback, the loopback unit 22
The data transmitted from the subscriber transmission device 30 is looped back.

The subscriber transmission device 30 is an adapter that is installed facing the plurality of network terminating devices 20a to 20c, and exchanges information with these devices by digital signals. In addition, the optical signal transmitted from the exchange 40 is converted into a 2B1Q (2binary 1 quaternary) signal by photoelectric conversion, and the 2B1Q signal, which is an internal signal, is converted into a corresponding optical signal and transmitted to the exchange 40.

FIG. 4 is a block diagram showing a detailed configuration example of the subscriber transmission device 30. In this figure, I / F
The (Interface) 30a converts the optical signal transmitted from the exchange 40 into a corresponding 2B1Q signal by photoelectric conversion, converts the internal 2B1Q into a corresponding optical signal, and transmits the signal to the exchange 40.

The cross-connect unit 30b accommodates a plurality of transmission lines and connects them to another transmission line, and connects / branches a low-speed line channel from an arbitrary transmission line to an arbitrary transmission line.

The subscriber circuit 30c is provided for each subscriber, and loops back data output from the cross-connect unit 30b when requested by the system control unit 30h. When loopback is performed in the network terminating device, a process of turning on a predetermined control bit is performed.

The switch 30d is connected to a subscriber line test unit 30g.
Switches the connection of the subscriber line 25 from the subscriber circuit 30c to the subscriber line test unit 30g.

The error measuring section 30e is provided with the pattern generating section 3
1 and an error detection unit 32, and when performing a test by loopback, the pattern generation unit 3
1 to generate data having a predetermined pattern, and the error detection unit 32 measures the error occurrence rate of the looped-back data.

The protocol processing unit 30f includes, for example, an IT
-G. of the UT recommendation. In accordance with the 965 (V5.2) protocol, communication control such as call connection control, failure processing, communication path control, and subscriber control is performed.

The subscriber line testing unit 30g includes a voltage detecting unit 3
3, a resistance detection unit 34 and a capacitance detection unit 35, which measure the voltage, resistance and capacitance of the subscriber line 25 and notify the system control unit 30h.

The system control unit 30h controls each unit of the apparatus, and when a test for a predetermined network termination device is requested from the subscriber test console 38, a test for specifying a failure in a predetermined order. Execute

The subscriber test console 38 is composed of, for example, a workstation or the like. When a telephone number or the like to be tested is inputted, the subscriber test console 38 refers to a built-in database and refers to a corresponding network. Termination device I
D is acquired and supplied to the system control unit 30h to request the test.

Next, the operation of the above embodiment will be described. FIG. 5 is a flowchart illustrating an example of a process performed in the embodiment illustrated in FIG. When this processing is started, the following processing is executed. [S1] The subscriber test console 38 receives an input of a subscriber telephone number to be tested. [S2] The subscriber test console 38 refers to a database or the like stored in a built-in storage device or the like to acquire the ID of the network terminating device corresponding to the entered subscriber telephone number. [S3] The subscriber test console 38 refers to the acquired ID, determines whether the service required by the target subscriber (subscribed service) is ISDN, and determines that the service is ISDN. Proceeds to step S4, and otherwise (for example, PSTN), ends the process.

The service demanded by the subscriber is P
In the case of STN, for example, a subscriber line test may be performed by the subscriber line test unit 30g. [S4] The subscriber test console 38 notifies the obtained ID to the system control unit 30h and requests execution of the test. [S5] The system control unit 30h sets the protocol processing unit 3
It supplies an ID to 0f and requests a check (busy check) as to whether the corresponding network terminating device is currently communicating. [S6] The system control unit 30h sends the protocol processing unit 3
As a result of the inquiry to 0f, if the target network terminating device is communicating, the process returns to step S6 and repeats the same processing. Otherwise, the process proceeds to step S7. [S7] The system control unit 30h switches the connection of the switch 30d to the subscriber line test unit 30g, and requests the subscriber line test unit 30g to test the subscriber line.

As a result, the subscriber line test unit 30g
, The electrical characteristics of the subscriber line are measured based on the processing described later. [S8] The system control unit 30h performs a loopback test on the target network termination device.

The details of this process will be described later with reference to FIG. [S9] The system control unit 30h performs a loopback test on the target subscriber circuit.

The details of this process will be described later with reference to FIG. [S10] The system control unit 30h refers to the results of the electrical test, the loop-back test of the network termination device, and the loop-back test of the subscriber's circuit to determine the location of the failure.

FIG. 6 is a diagram showing the relationship between test results and fault locations. As shown in the first item of the figure, when all the inspection results are “OK”, the subscriber transmission device 30 is normal and other equipment (for example, subscriber equipment,
The exchange 40, or the exchange 40 and the subscriber transmission device 30
May have failed.

The second item is a case where only the result of the electrical test is "NG". In this case, a failure of the subscriber line is considered. The third item is a case where both the electrical test and the loopback result of the network termination device are "NG". In this case, it is considered that a failure of the subscriber line and a failure of the network termination device occur. Can be

The fourth item is a state where only the loopback result of the network terminating device is "NG". In this case, it is considered that the network terminating device has failed. The fifth item is a case where the loopback result of the subscriber circuit 30c is "NG". In this case, the failure of the subscriber circuit 30c is considered regardless of the loopback result of the network termination device. [S11] The system control unit 30h compares the test result and the determination result in step S10 with the subscriber test console 38.
To be displayed. Then, the process ends.

According to the above-described processing, the test object is automatically specified only by inputting the telephone number of the target subscriber from the subscriber test console 38, and the test is executed when it is determined that the user is not on a call. Therefore, the burden on the tester can be reduced.

In addition, a series of tests are automatically executed, and a failure occurrence location is estimated and displayed based on the test result, so that it is possible to shorten the time until failure recovery.

Next, referring to FIG. 7, step S in FIG.
The details of the “electric test” shown in FIG. 7 will be described. When this flowchart is started, the following processing is executed. [S20] The voltage detection unit 33 of the subscriber line test unit 30g
DC (Direct) between AB, AG, and BG of the subscriber line 25
Current) Measure the voltage.

Here, A and B indicate each of the two signal lines, and G indicates the ground. Therefore, between AB and between two signal lines, between AG and between BG indicate between each of the two signal lines and the ground. [S21] The voltage detection unit 33 determines whether the subscriber line 25
An AC (Alternating Current) voltage between AG and BG is measured. [S22] If any of the AC voltages detected in step S21 exceeds 8 V, the system control unit 30h ends the processing to prevent the subscriber line test unit 30g from failing due to overvoltage. Otherwise, the process proceeds to step S23. [S23] If the absolute value of the DC voltage between the AGs detected in step S20 is less than 8 V, the system control unit 30h proceeds to step S24. Otherwise, the subscriber line test is performed by overvoltage. The process ends to prevent the unit 30g from breaking down. [S24] If the absolute value of the DC voltage between the BGs detected in step S20 is lower than 8 V, the system control unit 30h proceeds to step S25. The process ends to prevent the unit 30g from breaking down. [S25] The resistance detection unit 34 of the subscriber line test unit 30g
The resistance value between AG and BG is measured. [S26] The capacity detection unit 34 of the subscriber line test unit 30g
The capacitance value between AG and BG is measured. [S27] If the absolute value of the DC voltage between A and B detected in step S20 exceeds 8 V, the system control unit 30h uses the overvoltage to set the subscriber line test unit 30h.
The processing is ended to prevent the failure of g, and otherwise, the process proceeds to step S28. [S28] The capacity detection unit 35 of the subscriber line test unit 30g
The capacitance value between AB is measured.

The result measured as described above is notified to the system control unit 30h, and the quality of the subscriber line is determined with reference to the table shown in FIG. FIG.
In the example, not only ISDN but also PSTN is illustrated.

As shown in FIG. 8, if the subscriber line is normal, all the second to seventh check items are included.
If the test result is out of the illustrated range, it is determined to be normal.

Here, the second item is "Abnormal ins
ulation ”(insulation abnormality), and either RAG (resistance between AG) or RBG (resistance between BG) is 6KΩ or more.
The case where it is in the range of 60 KΩ is applicable.

The third item is "Line break".
This corresponds to the case where RAB (resistance between AB) is more than 6 KΩ or CAB (capacity between AB) is less than 0.4 μF.

The fourth item is "Mixture line" (short circuit), which corresponds to the case where RAB is less than 1.5 KΩ. The fifth item is “Touch to earth” (ground), which corresponds to the case where RAG or RBG falls within the range of 0 KΩ to 6 KΩ.

The sixth item is "Line Carry Voltage"
(For example, contact with commercial power supply) and VA
This corresponds to the case where any one of B (voltage between AB), VAG (voltage between AG), and VBG (voltage between BG) exceeds 4V.

The seventh item is “Electric leakage”
(Leakage), CAG (capacity between AG) or CBG
(Capacity between BG) exceeds 0.5 μF. If none of the above items apply, the subscriber line is determined to be normal.

Next, referring to FIG. 9, step S in FIG.
The process “loopback test for network termination device” shown in FIG. 8 will be described in detail. When this flowchart is started, the following processing is executed. [S30] The system control unit 30h sets the subscriber circuit 30c
Is transmitted to the network terminating device with a predetermined control bit (control bit for requesting loopback) turned ON.

As a result, in the corresponding network terminating device, FIG.
The detection unit 21 detects that the control bit is turned on, and notifies the loopback unit 22. The loopback unit 22 loops back the data transmitted from the subscriber transmission device 30 according to the notification from the detection unit 21. [S31] The system control unit 30h sets the error measurement unit 30
The generation of data having a predetermined pattern is started by the pattern generation unit 31 of e.

The data generated by the pattern generating unit 31 is transmitted to the network terminating device via the cross-connect unit 30b, the subscriber circuit 30c, and the switch 30d, where the data is looped back and the error is transmitted via the same route. It will be received by the detection unit 32. [S32] The error detector 32 determines whether or not the data generation has been completed.
The process proceeds to step S33, and otherwise returns to step S32 and repeats the same processing. [S33] The error detection unit 32 calculates an error occurrence rate by comparing the received data with the original data generated by the pattern generation unit 31. [S34] The error detection unit 32 notifies the system control unit 30h of the error occurrence rate calculated in step S33. [S35] The system control unit 30h sets the subscriber circuit 30c
Is controlled, and data in which a predetermined control bit (control bit for requesting loopback) is turned off is transmitted to the network terminating device.

As a result, the corresponding network terminating device
The detection unit 21 detects that the control bit is turned off, and notifies the loopback unit 22.
The loopback unit 22 receives the notification from the detection unit 21
Stop looping back data.

According to the above processing, it is possible to cause a predetermined network terminating device to execute data loopback and measure the error occurrence rate. Next, with reference to FIG. 10, the details of the “loopback test of the subscriber circuit” shown in step S9 of FIG. 5 will be described. When this flowchart is started, the following processing is executed. [S40] The system control unit 30h sets the subscriber circuit 30c
Is set to loop back the data from the cross-connect unit 30b. [S41] The system control unit 30h sets the error measurement unit 30
The generation of data having a predetermined pattern is started by the pattern generation unit 31 of e.

The data generated by the pattern generating section 31 is transmitted to the subscriber circuit 30c via the cross-connect section 30b.
Supplied to The subscriber circuit 30c makes the supplied data loop back to the cross-connect unit 30b. As a result, the data that has been looped back is
Will be received. [S42] The error detector 32 determines whether or not the data generation has been completed.
The process advances to step S43, and otherwise returns to step S42 and repeats the same processing. [S43] The error detection unit 32 calculates an error occurrence rate by comparing the received data with the original data generated by the pattern generation unit 31. [S44] The error detection unit 32 notifies the system control unit 30h of the error occurrence rate calculated in step S43. [S45] The system control unit 30h sets the subscriber circuit 30c
To stop the loopback operation.

According to the above processing, it is possible to cause the subscriber circuit 30c to execute loopback of data and measure the error occurrence rate. As described above, according to the embodiment of the present invention, it is possible to reduce the burden on the person who performs the test, and to perform the subscriber test in a short time and at low cost. Become.

In the above embodiment, ISDN is taken as an example of a communication network, and V is used as a communication protocol.
Although description has been made by taking 5.2 as an example, the present invention is not limited to only such a case.

[0066]

As described above, according to the present invention, a subscriber transmission apparatus, which is disposed between an exchange and a network terminating apparatus and relays information between them according to a predetermined protocol, is to be tested. Target identification means for identifying the predetermined network termination device; communication detection means for detecting whether or not the predetermined network termination device identified by the target identification means is communicating; Accordingly, a test means for testing characteristics relating to a communication state with the network terminating device specified by the target specifying means,
The subscriber test can be reliably executed in a short time.

[Brief description of the drawings]

FIG. 1 is a principle diagram for explaining the operation principle of the present invention.

FIG. 2 is a diagram illustrating a configuration example of an embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration example of a network termination device illustrated in FIG. 2;

FIG. 4 is a diagram showing a detailed configuration example of the subscriber transmission device shown in FIG. 2;

FIG. 5 is a flowchart illustrating an example of a process performed in the embodiment shown in FIG. 4;

FIG. 6 is an example of a table referred to when determining a test result.

FIG. 7 is a flowchart illustrating details of an “electric test” shown in FIG. 5;

FIG. 8 is a table referred to when judging the quality of a subscriber line from the measurement result of the electrical test shown in FIG. 7;

FIG. 9 shows a “loopback test of network termination device” shown in FIG.
6 is a flowchart for explaining details of FIG.

FIG. 10 is a flowchart illustrating details of a “subscriber circuit loopback test” shown in FIG. 5;

[Explanation of symbols]

 1a-1c Subscriber terminal 2a-2c Network termination device 3 Subscriber transmission device 3a Target specifying device 3b Detecting device during communication 3c Testing device 4 Switching device 10a-10c Subscriber terminal 20a-20c Network termination device 21 Detecting unit 22 Loopback unit Reference Signs List 30 subscriber transmission device 30a I / F 30b cross-connect unit 30c subscriber circuit 30d switch 30e error measurement unit 30f protocol processing unit 30g subscriber line test unit 30h system control unit 31 pattern generation unit 32 error detection unit 33 voltage detection unit 34 Resistance detector 35 Capacity detector 40 Exchanger

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K019 AA02 AA08 AC09 BA52 BA61 BB03 BB31 BB35 CC01 CC14 CC15 CC16 CD08 CD11

Claims (4)

[Claims] 1. A subscriber transmission device disposed between an exchange and a network terminating device for relaying information between them based on a predetermined protocol, for specifying a predetermined network terminating device to be tested. Specifying means, during-communication detecting means for detecting whether or not the predetermined network terminating device specified by the target specifying means is communicating, and according to the detection result of the during-communication detecting means, the target specifying means Test means for testing characteristics relating to a communication state with the network terminating device specified by the above. 2. The subscriber transmission apparatus according to claim 1, wherein said test means includes an electric characteristic measuring means for measuring an electric characteristic of a communication line with said network terminating device. 3. The test means includes: a pattern data generating means for generating data having a predetermined pattern; and a test circuit for looping back the data generated by the pattern data generating means in a subscriber circuit provided therein. 1 loopback means, second loopback means for looping back the data generated by the pattern data generating means in the network termination device, and loopback by the first or second loopback means. 2. The subscriber transmission device according to claim 1, further comprising: error detection means for detecting an error included in the data. 4. Comparing an error contained in the data looped back by the first loopback means with an error contained in the data looped back by the second loopback means. 4. The subscriber transmission apparatus according to claim 3, further comprising a fault occurrence point estimating means for estimating a fault occurrence point.