JPH0818532A - Monitor or multiplex converter monitor changeover system - Google Patents

Abstract

PURPOSE:To surely and quickly detect even a very small fault such as deterioration in quality of a transmission line by comparing transmission signals of each part of a transmission path of a transmission network and detecting a very small fault as an error. CONSTITUTION:One of transmission signals received from branch connectors 18, 19 is fed to a demultiplexing multiplex converter 48 and the other is fed to a comparison monitor section 49. The converter 48 detects a parity error from a transmission signal and demultiplexes it and the result is fed to a data bit string comparison section 50, and a parity error detection signal is fed to a parity error counter section 51. The comparator section 50 compares the transmission signal bit strings before multiplexing and after demultiplexing from the connector 18 in the unit of bits and counts a comparison errors when dissident. Simultaneously the counter section 51 counts number of parity errors from the parity error detection signal and the counted comparison error and parity error are fed to an in-station line concentrator, where they are monitored centralizingly. As a result, when a very small fault takes place at a point C, the very small fault is surely and quickly detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an independent synchronous digital hierarchy (PDH) having a stuffing multiplexer for inserting a stuffing pulse for synchronization adjustment and synchronizing and multiplexing a signal train.
Iterative Hierarchy) transmission network, in particular,
In the PDH system transmission network, a multiplex converter monitoring switching system capable of reliably and promptly detecting even a minor failure that cannot be detected by a conventional monitoring method such as deterioration of the transmission path quality and significantly improving the reliability of the transmission network. Monitoring device.

[0002]

2. Description of the Related Art Generally, when a signal is transmitted between a plurality of stations, one station inserts a stuff pulse for synchronization adjustment to synchronize a PCM signal sequence, multiplex the signals and transmit them to the other station. At the other station, an independent synchronous digital hierarchy (hereinafter referred to as PDH system) transmission network is known, which is configured to separate and restore the transmitted multiplexed signal. In the PDH system transmission network, in order to detect a failure (that is, transmission error) on the transmission network, a parity bit is added to a transmission signal and transmitted, and the parity bit and the transmission result are collated, A parity monitoring method has been used in which a failure is judged when the level in the matching result is equal to or higher than a predetermined detection threshold.

However, with the above-described parity monitoring method, it is not possible to reliably and promptly detect a slight failure such as deterioration of the transmission line quality, as shown below. First,
For example, as shown in FIG. 6, a first multiplex conversion device 1 for stuff-multiplexing a plurality of signal sequences from a user and the first multiplex conversion device 1
In the PDH system transmission network having the second multiplexing and converting apparatus 2 which separates the multiplexed signal sequence from the multiplexing and converting apparatus 1 of No. 1 and supplies it to a plurality of users, deterioration of the transmission path quality (minor However, since the above-mentioned failure is a minor failure, the error level becomes below the detection threshold value. The above failure could not be detected. Therefore, in this case, there is a risk of being left untreated and causing complaints from the user.

Further, even if the detection threshold value is lowered so that the minor fault can be detected by the parity check, it takes a very long time and a lot of labor to limit the fault section as shown below. was there. That is, for example, as shown in FIG. 7, a first multiplex conversion device group 3 for stuff-multiplexing a plurality of signal sequences from a user or the like and the first multiplex conversion device group 3
A second multiplex conversion device 4 for further stuff-multiplexing a plurality of multiplexed signal sequences from the multiplex conversion device group 3 of FIG.
Repeater 5 for relaying and transmitting the multiplexed signal from the multiplex converter 4, the third multiplex converter 6 for separating the multiplexed signal sequence from the repeater 5, and the third
And a fourth multiplex converter group 7 for further separating the signal sequence from the multiplex converter 6 of FIG.
In the system transmission network, when the transmission line quality is deteriorated (minor failure) at the point B, the first to fourth multiplex conversion devices 3,
Even if the minor faults can be detected by the parity check of 4, 6, and 7, the faults are expressed only in the same multiplexing hierarchy (degree of multiplexing). Only 7 could detect it. Therefore, it is necessary to sequentially investigate each section from the fourth multiplex converter 7 in which the failure is detected to the point B, and it takes a very long time and much labor to limit the failure section. I was sick.

[0005]

The present invention has been made in view of the above circumstances, and in a PDH system transmission network, it is possible to reliably and quickly detect even a minor failure such as deterioration of transmission line quality that cannot be detected by conventional monitoring methods. It is an object of the present invention to provide a monitoring device for a multiple conversion device monitoring and switching system capable of significantly improving the reliability of a transmission network.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention multiplexes and transmits a plurality of transmission signals and separates the multiplexed and transmitted transmission signals to obtain an original signal. A monitoring device of a multiplex converter monitoring and switching system for monitoring a failure in an integrated transmission network compares transmission signals of respective parts taken in by branching means from respective parts of the transmission path of the transmission network, and regards a minor failure as an error It is characterized in that it is configured to detect. Another feature of the present invention is that the multiplex transmission network has a plurality of multiplex converters for multiplexing or demultiplexing the transmission signals, and the branching means has an input side and an output side of each of the multiplex converters. Of a plurality of branch connectors which are provided on the transmission path of the multiplexer and monitor and take in the transmission signal passing through the transmission path without affecting the transmission signal. Alternatively, a multiplexer / demultiplexer that separates a transmission signal from a branch connector provided on the input side, a signal from the multiplexer and a transmission signal from a branch connector provided on the input side or the output side of each of the multiplex converters And bit by bit, and if they are not exactly the same, a comparison monitoring unit that counts as a comparison error. Still another feature of the present invention is that the multiplexed transmission network has a relay device that relays the multiplexed transmission signal,
The branching means is provided on the transmission paths on the input side and the output side of the relay device, and comprises a large number of branch connectors that monitor and take in the transmission signals without affecting the transmission signals passing through the transmission paths. , The monitoring device compares the transmission signal from the branch connector provided on the output side of the relay device and the transmission signal from the branch connector provided on the input side of the relay device in bit units, and they are exactly the same. If not, it is composed of a comparison monitoring unit that counts as a comparison error. Still another feature of the present invention is that the above-mentioned multiplexed transmission network has an independent synchronous digital hierarchy (PDH: PDH) having a stuffing multiplexer for inserting a stuffing pulse for synchronization adjustment and synchronizing a signal train for multiplexing. Plesi
Ochronous Digital Hierarc
hy) A transmission network.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on illustrated embodiments. FIG. 1 is a block diagram showing a PDH system transmission network including an embodiment of a monitoring device of a multiplex converter monitoring switching system according to the present invention. As shown in FIG. 1, this PDH system transmission network includes a first multiplex converter group 8 for stuff-multiplexing a plurality of signal sequences from users and the like, and a plurality of multiplex converter groups 8 from the first multiplex converter group 8. A second multiplex conversion device group 9 for further stuff-multiplexing the multiplexed signal sequence, and a third multiplex conversion device 10 for further stuff-multiplexing the multiplexed signal sequence from the second multiplex conversion device group 9. , First and second relay devices 11 and 12 for relaying and transmitting the multiplexed signal from the third multiplexer / converter 10 and the multiplexed signal from the second relay device 12. A fourth multiplexer / demultiplexer 13 for separating the columns, a fifth multiplexer / demultiplexer group 14 for further separating the signal stream from the fourth multiplexer / converter 13, and a fifth multiplexer / demultiplexer group 14 for separating the signal train. A sixth multiplex variable that further separates the signal sequence and supplies it to the user, etc. It is configured to have an apparatus group 15.

It should be noted that in FIG. 1, only one of the multiplex conversion device groups is shown and the others are omitted. Then, the first to sixth multiplexing and converting devices 8, 9, 10, 1
3, 14, 15 and the first and second relay devices 11,
A spare (not shown) is prepared for each of the transmission lines 12 and the transmission lines that connect them, and they can be switched to the respective spares when a failure occurs as described later. This PD
The H-system transmission network is provided with a multiplex converter monitoring switching system described below.

That is, as shown in FIG. 1, this multiplex converter monitoring and switching system includes the first multiplex converter group 8 as described above.
First and second branch connectors 16 and 17 provided on the transmission lines on the signal string input side and the signal string output side, respectively.
And third and fourth branch connectors 18 and 19 respectively provided on the signal line input side and signal line output side transmission lines of the second multiplex converter group 9, and the third multiplex converter 10 Of the fifth and sixth branch connectors 20 and 21 respectively provided on the signal line input side and the signal line output side of the transmission line, and the signal line input side and the signal line output side of the first relay device 11 described above. 7th and 8th branch connectors 22 and 23 respectively provided on the road, and 9th and 10th branch connectors respectively provided on the signal train input side and signal train output side transmission lines of the second relay device 12. Branch connectors 24 and 25, and eleventh and twelfth branch connectors 26 and 27 provided on the signal line input side and signal line output side transmission lines of the fourth multiplexer 13 respectively.
And a thirteenth signal line provided on the signal line input side and the signal line output side of the fifth multiplex converter group 14, respectively.
And fourteenth branch connectors 28 and 29, and fifteenth and sixteenth branch connectors 30 and 31 provided on the signal line input side and signal line output side transmission lines of the sixth multiplexer / demultiplexer group 15, respectively. have.

The branch connectors 16 to 31 are
The main signal passing through the transmission line is not affected and the main signal is monitored and pulled in and output. A first monitoring device 32 is connected to the output side of the first and second branch connectors 16 and 17, and a second monitoring device is connected to the output side of the third and fourth branch connectors 18 and 19. A device 33 is connected, a third monitoring device 34 is connected to the output sides of the fifth and sixth branch connectors 20, 21, and a third monitoring device 34 is connected to the output sides of the seventh and eighth branch connectors 22, 23. A fourth monitoring device 35 is connected, and a fifth monitoring device 35 is connected to the output sides of the ninth and tenth branch connectors 24 and 25.
Monitoring device 36 of the sixth monitoring device 3 is connected to the output side of the eleventh and twelfth branch connectors 26, 27.
7 is connected, a seventh monitoring device 38 is connected to the output side of the 13th and 14th branch connectors 28, 29, and the 15th and 16th branch connectors 30, 31 are connected.
An eighth monitoring device 39 is connected to the output side of the.

Then, the first to third monitoring devices 32 to
34 denotes a first intra-station concentrator 40 and a packet network 41.
Connected to a centralized monitoring device 42 via the network, and the fourth and fifth monitoring devices 35 and 36 are connected to the second and third intra-station concentrators 43 and 44 and the packet network 4, respectively.
Is connected to the central monitoring device 42 via the
~ The eighth monitoring devices 37 to 39 are the fourth intra-station concentrator 4
5 and the packet network 41, and is connected to the centralized monitoring device 42. Then, the centralized monitoring device 42
A switching system 46 and an alarm concentration center 47 are connected to the.

Next, the above first to third monitoring devices 32 to 3
The configuration of No. 4 will be described with reference to FIG. FIG. 2 is a diagram showing an internal configuration of the monitoring device, and in this case, an example of the second monitoring device 33 is shown. As shown in FIG. 2, the second monitoring device 33 includes the fourth branch connector 1
A demultiplexing multiplexer 48 connected to the output side of 9;
Comparison and monitoring section 4 connected between the output side of the third branch connector 18 and the output side of the demultiplexing multiplexer / demultiplexer 48.
9 and the comparison and monitoring section 49 includes a data bit string comparison section 50 and a parity error counting section 51. Also, the sixth to eighth monitoring devices 37 to 39 described above.
As shown in FIG. 3, the basic configuration is the same as that of the first to third monitoring devices except that the directions of multiplexing and demultiplexing are different. Here, FIG. 3 shows an example of the sixth monitoring device 37. Incidentally, the above-mentioned fourth and fifth
Since the first and second relay devices 11 and 12 do not perform the multiplexing, the monitoring devices 35 and 36 of FIG. 4 have the output side of the seventh and eighth branch connectors 22 and 23 as shown in FIG. It is only the comparison and monitoring unit 52 connected to. However, in this case, the comparison and monitoring section 52 also performs a parity check. Here, FIG. 4 shows the fourth
The example of the monitoring device 35 of FIG.

Next, the operation of the multiplex converter monitoring and switching system of the PDH system transmission network having the above configuration will be described. First, as a multiplexed transmission, a signal sequence sent from the user or the like to the first multiplex conversion device group 8 is sequentially multiplexed by the first to third multiplex conversion devices 8, 9 and 10. , Is sent to the fourth multiplex converter 13 via the first and second repeaters 11 and 12, and the fourth to sixth multiplex converters 13, 14 and 15 in turn reverse the multiplexing. Are sequentially separated and sent to users and the like. Here, a parity bit for parity monitoring is added to the transmission signal. In the multiplexed transmission, the transmission signals are pulled in by the first to sixteenth branch connectors 16 to 31 without affecting the transmission signals on the transmission path, and the first to eighth monitoring devices 32 are provided. ~ 39 respectively monitored as described below.

Here, the first to third monitoring devices 32 to
The monitoring operation of 34 will be described with reference to FIG. 2 by taking the second monitoring device 33 as an example. As shown in FIG. 2, in the multiplex transmission, the third and fourth branch connectors 1 described above are used.
One of the transmission signals drawn in by the signals 8 and 19 is sent to the demultiplexing / multiplexing device 48, and the other is sent to the comparison and monitoring unit 4.
Sent to 9. The transmission signal sent to the demultiplexing multiple conversion device 48 is separated at the same time that the demultiplexing multiple conversion device 48 detects a parity error. Then, the separated transmission signal is sent to the data bit string comparison unit 50, and the parity error detection signal is sent to the parity error counting unit 51. In the data bit string comparison unit 50, the third branch connector 18
The bit string of the transmission signal before being multiplexed and the bit string of the separated transmission signal are compared in bit units,
If they are not exactly the same, it is counted as a comparison error. At the same time, in the parity error counting section 51,
Parity errors are counted from the parity error detection signal. Then, the counted comparison error and parity error are sent to the first intra-station concentrator 40,
Centralized monitoring is performed as described below.

Therefore, according to the monitoring apparatus having the above-mentioned configuration, for example, when the transmission line quality deterioration (minor failure) occurs at the point C in FIG. 2, the transmission signal bit string to be compared by the data bit string comparing unit 50. Are not the same and the comparison errors are counted, so that the above-mentioned minor failure can be detected reliably and quickly. Regarding the monitoring operations of the sixth to eighth monitoring devices 37 to 39, the directions of multiplexing and demultiplexing are different from those of the first to third monitoring devices. That is, as shown in FIG. 3, one of the transmission signals drawn in by the eleventh and twelfth branch connectors 26, 27 in the multiplex transmission is sent to the demultiplexing multiplexer 53 and the other is compared and monitored. Sent to section 49. The transmission signal sent to the demultiplexing multiplex converter 53 is demultiplexed while the parity error is detected in the demultiplexing multiplex converter 53. Then, the separated transmission signal is sent to the data bit string comparison unit 50, the parity error detection signal is sent to the parity error counting unit 51, and in the data bit string comparison unit 50, the twelfth branch connector. The bit string of the separated transmission signal from 27 and the bit string of the separated transmission signal are compared in bit units, and if they are not exactly the same, they are counted as a comparison error. At the same time, the parity error counting section 51 counts parity errors from the parity error detection signal. Then, the counted comparison error and parity error are sent to the fourth intra-station concentrator 45, and centralized monitoring as described later is performed. Therefore, also in this case, according to the monitoring device having the above-described configuration, for example, when the transmission path quality deterioration (minor failure) occurs at point D in FIG. 3, the transmission signal compared by the data bit string comparison unit 50. Since the bit strings are not the same and the comparison error is counted, the above-mentioned slight failure can be detected reliably and quickly.

Next, the above-mentioned fourth and fifth monitoring devices 3
The monitoring operations of Nos. 5 and 36 will be described with reference to FIG. 4 and taking the fourth monitoring device 35 as an example. As shown in FIG.
The transmission signals drawn in by the seventh and eighth branch connectors 22 and 23 in the multiplex transmission are both sent to the comparison and monitoring unit 52, and the data bit string comparison unit 54 of the comparison and monitoring unit 52 uses both of them. Are compared bit by bit, and if they are not exactly the same, they are counted as a comparison error. At the same time, the parity error detector 55 of the comparison monitor 52 detects and counts the parity error based on the transmission signal from the eighth branch connector 23. Then, the counted comparison error and parity error are sent to the second intra-station concentrator 43, and centralized monitoring as described later is performed. Therefore, according to the monitoring device having the above-described configuration, for example, when the transmission path quality deterioration (minor failure) occurs at point E in FIG. 4, the transmission signal bit strings compared by the data bit string comparison unit 54 are the same. However, since the comparison errors are counted, the above-mentioned minor failures can be detected reliably and quickly.

Next, the above first to eighth monitoring devices 32 to 3
The comparison error and the parity error from No. 9 are sent to the centralized monitoring device 42 via the first to fourth intra-station concentrators 40 to 45 and the packet network 41, respectively, and the centralized monitoring as described below is performed. That is, in the centralized monitoring device 42, the failure section is limited based on the notified comparison error and parity error, and an instruction to switch to a spare device is sent to the switching system 46 according to the level of the failure, and the failure section is notified. Is switched to a spare device, and an instruction to issue an alarm is issued by the alarm concentration center 47.
Sent to and an alarm is issued. Further, the failure section is displayed to the maintenance person, and the monitoring result is recorded as quality data for a long period of time and displayed at a desired time.

Next, another embodiment of the present invention will be described. In the above-described embodiment, one monitoring device is provided for one monitored object. For example, although the first multiplex conversion device group 8 shown in FIG. 1 is not shown, It is composed of 12 multiplex conversion devices 8, and as a result, 36 monitoring devices are required, which is very large scale. Therefore, in another embodiment of the present invention, a large number of monitored objects are monitored by one monitoring device. Therefore, a time-division switching device is provided between the monitored object and one monitoring device so that the large number of monitored objects are sequentially scanned and monitored.

With reference to FIG. 5, the detailed structure of this embodiment will be described by taking the first multiplex converter group 8 shown in FIG. 1 as an example. In FIG. 5, the time division switching device 5
Reference numeral 6 denotes a first branch connector group 16 provided on the input side of the first multiplex converter group 8 and connected to the first branch connector group 16.
And the second selectors 57 and 58, and the third selector 5 connected to the first and second selectors 57 and 58.
9 and a fourth branch connector group 17 provided on the output side of the first multiplex converter group 8 respectively.
And a fifth selector 60, 61 and a sixth selector 6 connected to the fourth and fifth selectors 60, 61.
And 2. The third and sixth selectors 59 and 62 are connected to the single monitoring device 63. Then, the time-division switching device 56 uses the large number of monitored objects (3 × 3 = 9 in the case of the example shown in FIG. 5).
The above-mentioned one monitoring device 63
Sequentially scans and monitors the large number of monitored objects.
Therefore, according to the second embodiment, the number of monitoring devices can be significantly limited, so that the entire device can be downsized and
The cost can also be reduced.

In the above description, the first multiplexer / demultiplexer group 8 shown in FIG. 5 has been described, but the description has been given to the case of the multiplexer / relay device other than the first multiplexer / converter group 8. The description is omitted because it is the same as the case of the example.
Further, in the explanation example shown in FIG. 5, only nine monitored objects are shown, but the first, second, fourth, and fifth selectors 57, 58, 60, 61 are further monitored. It goes without saying that you can add targets. In addition, the first
~ For the sixth selectors 57 to 62, semiconductor switches that can operate in a short cycle are used.

[0021]

As described above, according to the present invention, a monitoring device for performing comparative monitoring is connected to each of the multiplex conversion devices and relay devices so that a minor failure can be monitored.
In the DH system transmission network, even a minor failure that cannot be detected by the conventional monitoring method such as deterioration of the transmission line quality can be surely and quickly detected, and the reliability of the transmission network can be remarkably improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a PDH system transmission network including an embodiment of a monitoring device of a multiplex converter monitoring switching system according to the present invention.

FIG. 2 is an internal configuration diagram of a second monitoring device shown in FIG.

FIG. 3 is an internal configuration diagram of a sixth monitoring device shown in FIG.

4 is an internal configuration diagram of a fourth monitoring device shown in FIG. 1. FIG.

FIG. 5 is a main part configuration diagram of another embodiment of the multiplex converter monitoring and switching system according to the present invention.

FIG. 6 is an explanatory diagram of problems in a conventional PDH system transmission network.

FIG. 7 is an explanatory diagram of a problem of a conventional PDH system transmission network.

[Explanation of symbols]

1, 2, 3, 4, 6, 7, 8, 9, 10, 13, 14,
15 ... Multiplexing device, 5, 11, 12 ... Relay device, 1
6, 17, 18, 19, 20, 21, 22, 23, 2
4, 25, 26, 27, 28, 29, 30, 31 ... Branch connector, 32, 33, 34, 35, 36, 37, 3
8, 39 ... Monitoring device, 40, 43, 44, 45 ... Intra-station concentrator, 41 ... Packet network, 42 ... Centralized monitoring device,
46 ... Switching system, 47 ... Warning centralized center, 48 ... Separation multiplex converter, 4
9, 52 ... Comparison monitoring unit, 50, 54 ... Data bit string comparison unit, 51, 55 ... Parity error counting unit, 56 ... Time division switching device, 57, 58, 59, 6
0, 61, 62 ... Selector,

Claims (6)

[Claims] 1. Multiplexing for monitoring a fault in a multiplex transmission network for multiplexing and transmitting a plurality of transmission signals and separating the transmission signals transmitted in the multiplexed manner to obtain an original signal. A monitoring device of a converter monitoring and switching system, characterized by comparing transmission signals of respective parts taken in by branching means from respective parts of a transmission path of the transmission network, and detecting a minor failure as an error. Monitoring device for device monitoring switching system. 2. The multiplex transmission network has a plurality of multiplexers for multiplexing or separating the transmission signals,
The branching means is provided on the transmission paths on the input side and the output side of each of the multiplex conversion devices, and a large number of branch connectors for monitoring and fetching the transmission signals without affecting the transmission signals passing through the transmission paths. The monitoring device for a multiplex converter monitoring and switching system according to claim 1, comprising: 3. A multiplexer that separates a transmission signal from a branch connector provided on an output side or an input side of each of the multiplex converters, and a signal from the multiplex converter and each of the multiplexors. 3. A comparison monitoring unit for comparing bit by bit with a transmission signal from a branch connector provided on the input side or the output side of the conversion device and counting as a comparison error if they are not exactly the same.
A monitoring device of the multiplex converter monitoring and switching system described in 1. 4. The multiplexed transmission network has a relay device for relaying the multiplexed transmission signal, and the branching means is provided on a transmission path on an input side and an output side of the relay device. 2. The monitoring device for a multiple conversion device monitoring and switching system according to claim 1, further comprising a plurality of branch connectors which monitor and take in the transmission signal without affecting the transmission signal passing through the transmission path. . 5. The monitoring device compares, in bit units, a transmission signal from a branch connector provided on the output side of the relay device and a transmission signal from a branch connector provided on the input side of the relay device. The monitoring device of the multiplex converter monitoring and switching system according to claim 4, further comprising: a comparison monitoring unit that counts as a comparison error if they are not exactly the same. 6. The independent synchronous digital hierarchy (PDH: Plesiochronous D) in which the multiplex transmission network has a stuff multiplex conversion device for inserting a stuff pulse for synchronization adjustment and synchronizing and synchronizing a signal sequence.
2. The monitoring device of the multiplex converter monitoring and switching system according to claim 1, wherein the monitoring device is a digital Hierarchy) transmission network.