JPS61148933A - Multiplex line concentration system - Google Patents

Abstract

PURPOSE:To attain ease of fault check at fault of a relay line by constituting the titled system of a pattern generating collating means and a multiplex line concentrating means and providing a control means for applying multiplex control to a faulty circuit. CONSTITUTION:If a fault takes place in a relay line 306, a modulator- demodulator 304 detects a line fault, transmits a line quality deterioration signal to a multiplex line concentrator 303 and gives it to a control circuit 110 via a level converting circuit 116. The circuit 110 supervises the line quality of a relay line and has a function of multiplex separation control, transmission/ reception of control information and input/output control of test pattern to which each low speed line data of transmission/reception circuits 105-108 is to be multiplexed in relay lines 1, 2. In controlling the test pattern from a pattern generating circuit 121 that the test pattern from a pattern generating circuit 121 is transmitted to the relay line 1 via the circuit 110 with multiplexing, a multiplex line concentration circuit 109 multiplexes the test pattern and transmits the result to the device 304 via a transmission/reception circuit 111 and a level converting circuit 114. The test pattern is returned by the device 304, collated with the transmission pattern to locate the fault.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a multiple line concentration system for digital communication equipment.

In particular, the present invention relates to a multiplexing and concentrating system that allows easy troubleshooting in the event of a fault in a trunk line.

〔overview〕

In a method of multiplexing and concentrating a large number of digital low-speed signals onto a small number of relay lines, a test pattern generating and checking means is provided, and by manipulating this means to connect to the relay line, it is possible to investigate the failure state of the relay line. This is how it was done.

[Conventional technology]

In general, a multiplexing line concentrator is installed oppositely between a terminal device and a communication control device provided at a center station via a relay line and a modem. FIG. 2 shows a plurality of terminal devices 209
FIG. 3 is a configuration diagram of a conventional system in which data is multiplexed by a multiplexing line concentrator 207 and data is transmitted between the multiplexing line concentrator 203 installed on the opposing communication control device 201 side using a relay port vAz.

In FIG. 2, from the communication control device 201 to the terminal device 20
9 is communicated to the multiplexing line concentrator 2 through the low-speed line 202.
03, and after multiplexing, the modulators 204 and 21
0 and transmitted to the other party's modem equipment 206 and 212 through trunk lines 205 and 21), where it is demodulated and input to the multiplex concentrator 207. Here, the data is separated into data for each terminal device and transmitted to each terminal device 209 through the low-speed line 208. Data from each terminal device 209 is sent to the communication control device 209 through the reverse route to the above.
1.

Furthermore, in the conventional example shown in FIG. 3, the first trunk line 305, 306
If a failure such as line quality deterioration or line disconnection occurs at the point marked with an x, the modulator/demodulator 304 detects this failure and sends a reception carrier disconnection or line quality deterioration signal to the multiplexing concentrator 303. is sent to the multiplex concentrator 303. When the multiplexing line concentrator 303 receives the fault detection signal, it recognizes the fault on the first trunk line l side and switches the low-speed line 30
All 18 lines are concentrated and multiplexed on the second trunk line 309 side, and at the same time, the opposing station is notified via the first trunk line 305 that the own station side has concentrated and multiplexed all eight lines on the second trunk line 309 side. The multiplexing line concentrator 3 that received this notification signal
In step 12, all eight low-speed lines on the terminal side are multiplexed to the second line 310 side.

Also, the transmission side of the modem 304, the reception side of the multiplexing line concentrator 303, or the relay line 3 of the modem 307
06, the multiplex concentrator, or the transmit side of the device 312, or if data transmission from the multiplex concentrator 312 to the multiplex concentrator 303 becomes abnormal, the above will also apply. Similarly, multiplexing and concentrating devices 303 and 312 perform concentrating and multiplexing to the second trunk line.

In this way, the trunk line 306 or the multiplex concentrator 30
3.312, modem device 304, or modem device 307 becomes a failure, it is necessary to investigate the failure location.

Here, the modem, 304.307 and trunk line 30
In the section 5.306, the return function and pattern generation matching function of the modem are used, or the section 304.3 of the modem is
07 can be disconnected from the multiplex concentrator 303, 312 and connected to external test equipment to perform testing.

(Problem to be solved by the invention) However, all the low-speed lines connected to the multiplexing line concentrators 303 and 312 are multiplexed and concentrated on the second trunk line side, and the first trunk line multiplexing unit and the first trunk It is not possible to perform a test that includes the line.For example, if the line side of the modem 304 is looped back, the multiplex concentrator 303
may determine that the first trunk line 305, 306 has become normal, but the opposing multiplexing line concentrator 312 determines that the failure on the first trunk line side continues and determines the location of the failure. becomes insufficient.

Furthermore, as mentioned above, in the conventional system, the multiplexing line concentrator 3
03 and 312 are performing multiplexing and concentrating to the second trunk line 309 and 310, respectively, and it was not possible to conduct a test including the first trunk line multiplexing unit and the first trunk line, and the trunk line 305
．． 306, the modulator/demodulator 304, 307, or the multiplex concentrator 303, 312 cannot be investigated.

The present invention solves the above-mentioned problems, and when a multiplexing line concentrator is connected using a plurality of trunk lines, each component section is The purpose of this invention is to provide a multiplexing and concentrating method that facilitates fault investigation.

[Means for solving problems]

The present invention provides a system for transmitting data using multiplexing line concentrators installed facing each other between a plurality of trunk lines, and when a failure occurs in the multiplexing line concentrator system on one of the trunk lines, the other one is normal. A multiplexing line concentration method for concentrating all low-speed lines on the line side, comprising a pattern generation matching means and a multiplexing line concentration means, and comprising a control means for controlling multiplexing to the faulty line side. [Operation] If a fault occurs in the first trunk line, the modem detects the line fault, sends a signal indicating line quality deterioration to the multiplexing line concentrator, and provides this to the control circuit. The control circuit monitors the quality of the first and second trunk lines, for example, and controls whether to multiplex to the first or second relay concentrator side, separation control, control information, and human output of the test pattern. We will also investigate failures in each relay line.

〔Example〕

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

Level conversion circuits 101 and 102 are respectively transmitting and receiving circuits 1
05.106 to multiplex concentrator circuit 109. Level conversion circuits 103 and 104 are coupled to multiplexing concentrator circuit 109 via transmitting and receiving circuits 107 and 108, respectively. The multiplexing line concentrator 109 is coupled to the modem 304 outside the multiplexing line concentrator 303 via the transmitter/receiver circuit 1) 1 and the level converter circuit 1) 4, and is further coupled to the first trunk line l. Similarly, transmitting/receiving circuit 1) 2, level conversion circuit 1) 5,
The modem 308 is coupled to the second trunk line 2 . The outputs of the modulators 304 and 308 are input to the control circuit 1)0 via the level conversion circuit 1)6. This control circuit 1)0
is coupled to the pattern generation circuit 121, the multiplexing concentrator circuit 109, and the transmitting/receiving circuit 1)3. This transmitting/receiving circuit 1) 3 is coupled to a tester 120 outside the multiplexing line concentrator 303 via a level conversion circuit 1) 7.

In FIG. 1, the multiplex concentrator 303 (or 3
12) are level conversion circuits 101 to 101 provided for low-speed lines.
104, transmitting/receiving circuits 105 to 10B, a multiplexing concentrating circuit 109, level conversion circuits 1) 4 and 1) 5 provided for high-speed lines, and transmitting/receiving circuits 1) 1 and 1) 2. A control circuit 1) 0, a level conversion circuit 1) 6 for line quality and carrier disconnection detection, a level conversion circuit 1) 7 for control information input/output, a transmitting/receiving circuit 1) 3, and a pattern generation circuit 121 are added to the device. There is.

If a failure occurs in 306 of the first trunk lines 305 and 306, the modem 304 detects the line failure and sends a line quality deterioration signal 51 to the multiplexed line concentrator bag W303, level conversion circuit 1) 6 to the control circuit 1)0. The control circuit 1)0 monitors the line quality of the first trunk line 306 and the second trunk line 310, and
It has demultiplexing control for determining whether each low-speed line data of the transmitting/receiving circuits 105 to 108 is multiplexed to the first trunk line side or the second trunk line side, transmission and reception of control information, and input/output control functions for test patterns. There is.

Here, when a fault in the first trunk line 306 is applied to the control circuit 1) 0, all data from each low-speed line is multiplexed to the transmitting/receiving circuit 1) 2 side of the second trunk line, and the level conversion circuit 1) 5 The signal is then sent to the modem 308 on the second trunk line side. Conversely, the multiplexed data signal from the modulator/demodulator 308 is separated into each low-speed line via the reverse path. In this state, the operation when investigating a fault location in one example of a trunk line will be described.

When investigating a fault location on the relay line 1 side using a tester 120 that can generate data signals input to each low-speed line, the tester 120 is used as a control information input/output unit 1).
Connect to 0. The test pattern from the tester 120 is applied to the control circuit 110 via the level conversion circuit 1) 7, the transmitting/receiving circuit 1) 3. The control circuit 1) 0 controls the input/output of the transmitter/receiver circuit 1) 3 to be multiplexed and concentrated on the -th relay line side of the multiplexing circuit 109 by manual operation during a fault test. Test pattern -
The receiver is passed to the relay line side. The multiplex concentrator circuit 109 sends a signal in which the test pattern is multiplexed to the transmitting/receiving circuit 1) 1, and sends it to the modulation/demodulation device 304 of the relay line 1 via the level conversion circuit 1) 4. Here, when the modem 304 is looped back to investigate the first trunk line, the multiplexed signal is added to the multiplex concentrator 303 again, and is returned to the tester 120 via the reverse path as described above, and the transmission pattern is verification is performed, making it possible to investigate the failure. At this time, in addition to the loopback 123 of the modem 304, when loopback is performed at the modem 307 and loopback at the transmitter/receiver circuit 1) 1, the multiplexed test pattern is transferred to the first trunk line corresponding section of the multiplex concentrator or the modulator/demodulator. After being folded back by the device 307, it is manually input to the tester 120.

In addition, if the pattern generation circuit 121 provided inside the device is operated and controlled so as to be multiplexed and concentrated on the trunk line 1 side via the control circuit 1)0 without using the tester 120, the pattern generation circuit 121 provided inside the device will be multiplexed and concentrated on the trunk line 1 side as described above. The test pattern can be multiplexed and concentrated, and by setting the turning point as described above, the test pattern returns to the pattern generation circuit 121 again.

Furthermore, the multiplexing line concentrators of the present invention are installed facing each other via the relay lines 1 and 2, and the pattern generation circuits 121 are operated simultaneously in the re-device without setting the loop back. If a failure occurs in the first trunk line 306, the failure is detected by the pattern generation circuit 121 on the multiplexing line concentrator 303 side.
No failure is detected on the modem 307 side.

〔Effect of the invention〕

As described above, failures occur when the control circuit controls the control information output section to multiplex and concentrate lines to which relay line, or when the pattern generation circuit similarly multiplexes and concentrates lines. This has the effect that it is possible to easily investigate failures in the trunk line corresponding section on the relay line side, the modem side, or the trunk line.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram showing a conventional system that performs multiplexing and demultiplexing using a plurality of relay lines. FIG. 3 is a block diagram showing the flow of signals when a failure occurs on the trunk line side in the conventional system shown in FIG. 2. 1.2...Relay line, 101.104.1) 4-1)
7...Level conversion circuit, 105.10B, 1) 1~
1) 3... Transmission/reception circuit, 109... Multiplex concentrator circuit, 1) 0... Control circuit, 120... Tester, 121
...Pattern generation circuit 122.123...Return, 201...Communication control device, 202.208.30
1...Low speed line, 203.207.303.312.
...Multiplex line concentrator, 204.206.210.212
．． 304.307.308.31)...modulation/demodulation device,
205.213.305.306...first trunk line,
209.313...Terminal device, 21). 214.30
9.310...Second relay line.

Claims (1)

[Claims] (1) It is connected between a large number of digital low-speed lines and multiple trunk lines, and includes a multiplexing concentrator circuit, and when a failure occurs in one of the trunk lines, the low-speed lines are multiplexed to a trunk line that is free of failure. The multiplex line concentrator system is equipped with a means for controlling the multiplex line concentrator circuit to condense lines, and includes an operating terminal that can be manually operated, and a test pattern generator that sends a specific pattern signal to the relay line and detects the response. The multiplexing concentrator circuit includes circuit means for connecting the transmission output and reception input of the test pattern generation and verification means, and the controlling means controls the circuit means by a signal from the operating end. A multiplexing and concentrating method characterized by including means for controlling.