JPH0423984B2 - - Google Patents

Description

[Detailed description of the invention] [Table of contents] Overview Industrial field of application Conventional technology Problems to be solved by the invention Means for solving the problems (Fig. 1) Working examples (Fig. 2, (Figure 3) Effects of the invention [Summary] It is possible to monitor or test the D channel by separating the D channel signal of the digital subscriber line, inserting a test signal and introducing it into the digital switching network. This is what I did.

[Industrial application field]

The present invention relates to a signal line introduction system for digital subscriber lines, and particularly to a system in which the signal line, that is, the D channel signal, is separated and introduced into the network in order to easily monitor and test it. .

[Conventional technology]

Integrated service digital network
Services Digital Network (ISDN) or Advanced Information and Communication System (Information Network)
In systems such as INS), a digital switching network is connected to a network termination device that can connect multiple terminals such as telephones, workstations, and facsimiles, and 2B+D digital signals, that is, PCM such as voice, are transmitted to B1 and B2. A digital signal consisting of a D channel (64 Kb/s) and a control signal D channel (16 Kb/s) is transmitted on the subscriber line.

By the way, among these data, B1 and B2 data are sent to the destination via the digital switching network, so
If you want to monitor or test this, you can connect a monitor device or test device to the digital exchange network and selectively connect the data of these B channels to the monitor device or test device. It is possible.

[Problem that the invention seeks to solve]

However, the data of the D channel, which is a control signal, is connected to the data link control section on the processor side and undergoes processing such as flag detection and CRC check code checking, so it is transmitted to the digital switching network and monitored. It was not possible to switch to equipment or test equipment. Therefore, in order to monitor the D channel, one must select the transmission line connected to the data link control section from the printed circuit board and apply a probe to it to monitor the data, or one must monitor the data on the printed circuit board. There is a problem in that it is necessary to disconnect the transmission line and insert test data, and it is not possible to easily monitor or test the transmission line.

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to connect a D channel of a digital subscriber line to a digital switching network in order to improve the above-mentioned problems.

[Means for solving problems]

In order to achieve the above object, in the present invention, as shown in FIG. A signal for controlling the D channel, which is also obtained from the subscriber circuit 1, is transmitted to the mixer 5. The mixer 5 transmits this to the D channel processing section 6, and the processor provided in the D channel processing section 6 performs flag detection, CRC check, etc. The mixer 5 not only transmits the D channel signal to the digital switching network 4 via the multiplexer 3, but also has an inserter so that it can send the signal to the digital subscriber circuit 1.

[Effect]

Since the mixer 5 can transmit the D channel to the digital switching network 4 via the multiplexer 3, this D channel can be monitored by the monitor device 7, and the test trunk device 8 can insert a test signal and check the return status. You can perform tests such as checking.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 2 and 3.

FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is a detailed diagram of the mixer.

In the figure, parts with the same symbols as in other figures indicate the same parts.
-0 to 1-n are digital subscriber circuits 1-0 to 1
-n, and network termination devices 2-0 . . . are connected to the digital subscriber circuit 1-0 as representatively shown. A plurality of terminals 10 (only one terminal is illustrated in FIG. 2) are connected to the network terminal devices 2-0.

Digital subscriber circuits 1-0 to 1-n are each provided with demultiplexers 11-0 to 11-n, which send two B channel signals on the digital subscriber line to multiplexer 3-0, and send a D channel signal to multiplexer 3-0. The signal is sent to mixer 5. Mixer 5 sends these D channel signals to multiplexer 3-
0 and also transmits it to the D channel processor 6.
checks this D channel signal and performs processing such as flag detection, CRC check, and request for retransmission in the event of an error.

The digital switching network 4 includes a multiplexer 3-0.
~3-m are connected, and not only data input/output is performed, but also a monitor device 7 and a test trunk device 8 are connected, and multiplexers 3-0 to 3-m
can be selectively connected.

As shown in FIG. 3, the mixer 5 selectively inserts signals into the signal lines No. 0 to No. n connecting the digital subscriber circuits 1-0 to 1-n and the D channel processing section 6. an inserter 51- for inserting test signals into signal lines No. 0 to No. n;
0 to 51-n, a selector 52-0 for selecting a monitor signal, a selector 52-1 for selecting a test signal, and the inserters 51-0 to 51-5.
1-n, selector 52-0, 5
2-1.

In addition, as the monitor device 7, for example, a serial
For example, a bit error measurement trunk can be used as the test trunk device 8 using a data scope.

Next, the operation of the present invention will be explained.

(1) When performing a test When performing a test, the control section 53 selects the inserter connected to the digital subscriber circuit connected to the digital subscriber line to be tested. For example, when testing the digital subscriber circuit 1-0, the control section 53 operates the inserter 51-0. At the same time, the control unit 53 selects the selector 52-1 and controls the data from the No. 0 signal line to be sent to the multiplexer 3. In this case, multiplexer 3 includes inserters 51-0 to 51-n and selector 5.
The signal line combination 2-1 is selected, and at this time the digital switching network 4 operates to connect the multiplexer 3 and the test trunk device 8.

Therefore, the D channel test data sent from the test trunk device 8 is transmitted to the No. 0 signal line via the inserter 51-0, and is transmitted to the digital subscriber circuit 1-0.
It is sent to the network terminal device 2-0. The response to this is sent from the network terminal device 2-0 to the digital subscriber circuit 1-0 to the signal line No. 0 to the selector 52.
-1-Multiplexer 3-Digital switching network 4
is transmitted to the test trunk device 8 via. The test trunk device 8 can test each of these parts by checking the D channel response signal returned in response to the sent test pattern.

(2) When performing monitoring When performing monitoring, the control section 53 causes the selector 52-0 to select the signal line connected to the digital subscriber line to be monitored.
For example, when monitoring the digital subscriber circuit 1-0, the selector 52-0 selects the signal line No.
The control unit 53 controls to select 0. In this case, the multiplexer 3 is the selector 52-0
When selected, the digital switching network 4 operates to transmit the output of the multiplexer 3 to the monitor device 7.

Therefore, the D channel signal passing through the network termination device 2-0 and the digital subscriber circuit 1-0 is sent to the monitor device via the signal line No. 0, the selector 52-0, the multiplexer 3, and the digital switching network 4. 7, the monitor device 7 can monitor the D channel signal by collecting and analyzing it.

〔Effect of the invention〕

The present invention makes it easy to monitor or test the D channel signal of any digital subscriber circuit. In other words, it is possible to connect the upstream/downstream signals of a specified line to the digital switching network, the upstream signal of the specified line can be connected to the digital switching network, and the downstream signal can be connected from the digital switching network. Therefore, the D channel signal of any line,
For example, it is very easy to monitor with a serial data scope or test with a bit error measurement trunk.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention, FIG. 2 is a configuration diagram of an embodiment of the present invention, and FIG. 3 is a detailed diagram of a mixer. DESCRIPTION OF SYMBOLS 1...Digital subscriber circuit, 2...Network termination device, 3...Multiplexer, 4...Digital switching network, 5...Mixer, 6...D channel processing section, 7...Monitor device, 8...Test・Trunk device.

Claims (1)

[Claims] 1. Network termination device 2 to which a digital terminal is connected.
In a digital network comprising a digital subscriber circuit 1 and a digital switching network, a separating means 11 for separating a B channel signal and a D channel signal is provided in the digital subscriber circuit 1.
, inserters 51-0 to 51-n provided on the down lines to each of the digital subscriber circuits 1-0 to 1-n and inserting test signals, and digital subscriber circuits 1-0 to 1-n to be monitored. a first selector 52-0 that selects a signal line for 1-n;
Digital subscriber circuit 1-0 to be tested
A second selector 5 that selects the signal line from 1-n
2-1, a mixer 5 having a control unit 53 for controlling these inserters and each selector, a monitor means 7 and a test means 8, which inserts a test signal into the D channel via the inserter, and which also has an optional mixer 5. A signal line lead-in system for a digital subscriber line, characterized in that the D channel of the line is selectively connected to a digital switching network, thereby making it possible to monitor and test the D channel signal.