JP2624166B2 - Multiplex transmission equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the SDH standard STM-
The present invention relates to an SDH synchronous multiplex transmission device (hereinafter, referred to as a multiplex transmission device) in an N high-speed signal transmission system, and more particularly to an improvement in an alarm issuing control means.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing an example of a conventional multiplex transmission device. In FIG. 2, this multiplex transmission apparatus transmits m STM-M (M is a natural number) low-speed signal.
(M is a natural number) low-speed signal interface units 1-1 to 1-m connected to each of the low-speed transmission paths;
Low-speed signal interface units 1-1 to 1-m and ST
A high-speed signal interface unit 2 connected between a single high-speed transmission line through which an MN (N is the product of M and m) high-speed signal is transmitted;
And an alarm processing unit 3 connected to the

[0003] In terms of distinguishing the multiplex transmission apparatus into transmission means and reception means, first, as transmission means, the low-speed signal interface units 1-1 to 1-m respectively perform frame synchronization of STM-M low-speed signals. And an SOH termination unit 101 that terminates RSOH and MSOH as section overhead (SOH), removes SOH and outputs a low-speed data signal including an AU pointer and a payload, which will be described later, and performs pointer termination processing and replacement processing. Pointer processing unit 1 that outputs the low-speed data signal to high-speed signal interface unit 2
02. The high-speed signal interface unit 2 includes the low-speed signal interface units 1-1 to 1-m
A multiplexing unit 201 for multiplexing the low-speed data signals from the respective units, and RSOH and MSO
And an SOH insertion unit 202 for inserting an H and outputting an STM-N high-speed signal to the high-speed transmission line.

On the other hand, as a receiving means, the high-speed signal interface unit 2 removes the SOH by performing frame synchronization and RSOH and MSOH termination processing on the STM-N high-speed signal input from the opposite device (not shown) through the high-speed transmission line. Terminating section 20 for outputting a high-speed data signal including an AU pointer and a payload
3, a separating unit 204 for separating a high-speed data signal into a plurality of low-speed data signals, a pointer termination process and a replacement process for each low-speed data signal to convert each low-speed data signal into a corresponding low-speed signal interface unit 1-1 to 1-1. 1-
m, a pointer processing unit 205 that identifies the state of the received pointer, and outputs a path AIS, which will be described later, and an alarm to the alarm processing unit 3 as an alarm when a pointer abnormality is detected. Each of the low-speed signal interface units 1-1 to 1-m includes an SOH insertion unit 103 that inserts RSOH and MSOH into a low-speed data signal from the pointer processing unit 205 and outputs an STM-M low-speed signal to a low-speed transmission line. In. The alarm processing unit 3 collects path AIS and pointer abnormality alarms detected by the pointer processing unit 205 and issues a path alarm indicating a path abnormality to the outside of the apparatus.

[0005] Here, the low-speed signal interface units 1-1 to 1-m are each provided with a single VC according to the interface of the device connected to the low-speed signal interface unit.
STM-n (n) containing one or more VC-3 signals, VC-4 signals, or VC-4 concatenation signals (described in the CCITT recommendation) from an STM-0 interface containing Is a natural number). Referring to FIG. 3A, the low-speed signal interface unit of the STM-0 interface has
It has an OH insertion unit 5, an SOH termination unit 6, and a pointer processing unit 7. Referring to FIG. 3B, S
The low-speed signal interface unit of the TM-n interface includes a multiplexing unit 8 and an SOH insertion unit 5, an SOH termination unit 6, a demultiplexing unit 9, and a pointer processing unit 7.

FIG. 4 is a block diagram showing an example of a system in which the multiplex transmission apparatus shown in FIG. 2 is used oppositely. still,
In FIG. 4, the alarm processing unit in the multiplex transmission device is not shown.

In FIG. 4, the system includes a low-speed signal interface unit (shown as low-speed INF in FIG. 4) 110-1 to 110-n and a high-speed signal interface unit (shown as high-speed INF in FIG. 4) 120. The multiplex transmission device 10 including the low-speed signal interface units 210-1 to 210-L (L is a natural number) and the high-speed signal interface unit 220
And a path terminating device 40. While the three low-speed signal interface units 110-1 to 110-3 in the multiplex transmission device 10 are operated by STM-0, the low-speed signal interface unit 210-1 in the opposing multiplex transmission device 20 is
Low-speed signal interface units 110-1 to 110
-3 is connected to the path terminating device 40 via the STM-1 interface.

The low-speed interface units 1-1 to 1-m in the multiplex transmission apparatus as shown in FIG.
On the other hand, not all low-speed signal interface units are necessarily mounted and operated, and some low-speed signal interface units may be operated without being mounted. Hereinafter, the latter case will be applied to the configuration shown in FIG.

Referring to FIG. 4, low-speed signal interface units 110-1 and 11 in multiplex transmission apparatus 10 are provided.
The multiplex transmission apparatus 10 is used in a state where the low-speed signal interface unit 110-3 is not mounted while the 0-2 is mounted. In this case, the low-speed signal interface unit 1 input to the high-speed signal interface unit 120
Since the low-speed data signal from 10-3 is in an open state, it is fixed at 1 or 0.

In the multiplex transmission apparatus as shown in FIG. 2, the high-speed signal interface unit uses the time slot corresponding to the AU pointer and the payload (ST ST in FIG. 5) among the signals input from the low-speed signal interface unit.
MN frame) is transmitted through the high-speed transmission line through-through, so that the STM-
In the N high-speed signals, a fixed value of 1 or 0 is transmitted to the AU pointer and the time slot of the payload corresponding to the low-speed data signal from the unmounted low-speed signal interface unit 110-3.

FIG. 6 is a diagram showing the configuration of an AU pointer corresponding to one VC-3. Referring also to FIG.
G. CCITT recommendations. In 709, if the received AU pointer is fixed at 1 for both H1 and H2, it is determined to be path alarm display information (hereinafter referred to as path AIS),
The received AU pointer is a normal pointer, NDF (“011
"0" or "1001"), if a pointer value that does not correspond to any of the above-described path AIS, positive stuff (I bit is inverted), and negative stuff (D bit is inverted) is received, it is determined that the pointer is abnormal. .

Referring again to FIG. 4, the multiplex transmission apparatus 20
Then, in the pointer processing unit of the high-speed signal interface unit 220, the status of the AU pointer for the multiplex transmission device 10 is determined and the AU pointer is replaced. At this time, the AU pointer for the low-speed signal interface unit 110-3 is 1 or Is a fixed value of 0,
According to the CITT recommendation, when the AU pointer is fixed at 1, it is determined that the path is AIS, and when the AU pointer is fixed at 0, it is determined that the pointer is abnormal. In any case, the unmounted low-speed signal interface unit 110-
Regarding 3, any one of the path warnings is issued even though the path is unused. And
Based on the determined result, a path alarm is issued by the alarm processing unit, and the path A in the high-speed signal interface unit 220 is output by the pointer processing unit.
IS is inserted and the low-speed signal interface unit 21
0-1 is sent to the path terminating device 40. That is, an unnecessary path AIS for the non-operational path spreads to the downstream device.

[0013]

As described above,
In the conventional multiplex transmission apparatus including the multiplex transmission apparatus shown in FIG. 2, only the low-speed signal interface unit required for operation is mounted, while when the unnecessary low-speed signal interface unit is operated without being mounted, the opposite apparatus is used. There is a problem in that it is not possible to distinguish whether a path alarm that is issued in response to an unmounted low-speed signal interface unit is due to a failure or to a non-mounted low-speed signal interface unit of an opposing device. For this reason, in order to prevent unnecessary path alarms from being issued for non-operational paths, the mounting state of the low-speed signal interface unit of the opposing device is set from outside the device, and based on this setting, the alarm processing unit Means must be provided, such as to prohibit the issuance of alarms, which not only complicates the configuration as a multiplex transmission apparatus, but also causes a problem that a user or a maintenance person is required to perform cumbersome work in maintenance management.

Incidentally, in Japanese Patent Application Laid-Open No. 3-212942,
There has been proposed an alarm suppression system in a transmission device itself. However, if the interface unit is not mounted on the opposing device, it is not subject to alarm suppression, and it has not been possible to prevent the issuance of an unnecessary path alarm or the spread of the unnecessary path AIS to the downstream device for the inactive path. .

It is an object of the present invention to provide a multiplex transmission apparatus capable of automatically recognizing a state of mounting a low-speed signal interface unit of an opposing apparatus and controlling generation of a path alarm in accordance with the recognition result.

Another object of the present invention is to automatically recognize the mounting state of the low-speed signal interface unit of the opposing device,
An object of the present invention is to provide a multiplex transmission device that can prevent a path alarm signal from spreading downstream according to a recognition result.

[0017]

According to the present invention, there is provided between a plurality of low-speed transmission lines and one high-speed transmission line,
After multiplexing a plurality of low-speed signals from a plurality of low-speed transmission paths, performing a transmission operation of inserting a section overhead and outputting as a high-speed signal, and removing a high-speed signal from the high-speed transmission path from the section overhead. And then outputs the plurality of low-speed signals to any of the plurality of corresponding low-speed side transmission paths, and issues a path alarm indicating a path abnormality based on the value of the pointer included in the separated low-speed signal. In the multiplex transmission apparatus that performs a receiving operation, the transmitting operation includes collecting each signal representing the opening and closing of each of the plurality of low-speed transmission paths as mounting operation information, and including the mounting operation information in the section overhead. The receiving operation is included in the section overhead removed from the high-speed signal. Multiplex transmission apparatus is obtained and performs an operation for controlling the emission of said path alarm based on the mounting operation information about the facing device.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multiplex transmission apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a multiplex transmission apparatus according to this embodiment. In the figure, the same or similar parts as in the conventional example are denoted by the same reference numerals as in FIG. 2 and will not be described in detail.

In FIG. 1, this multiplex transmission apparatus is connected to each of m (m is a natural number) low-speed transmission lines through which STM-M (M is a natural number) low-speed signals are transmitted, as in the conventional example. Low-speed signal interface units 1-1 to 1--1
m, low-speed signal interface units 1-1 to 1-m
And a STM-N (N is the product of M and m) high-speed signal interface unit 2 connected to one high-speed transmission line for transmitting a high-speed signal, and connected to high-speed signal interface unit 2 The low-speed signal interface units 1-1 to 1-m include an SOH termination unit 101, a pointer processing unit 102, and an SOH insertion unit 103, respectively. Multiplexer 201 and SOH inserter 20
2, an SOH termination unit 203, a separation unit 204, and a pointer processing unit 205.

Further, the multiplexing apparatus has a specific configuration described below.

First, as transmission means, the low-speed signal interface units 1-1 to 1-m each generate a mounting signal indicating that they are mounted and output the mounting signal to the high-speed signal interface unit 2. 104
Contains. That is, among the low-speed signal interface units 1-1 to 1-m, the mounted signal is not output from the unmounted low-speed signal interface unit.

The high-speed signal interface unit 2 collects the mounting signals from the low-speed signal interface units 1-1 to 1-m, and collects the low-speed signal interface units 1-1 to 1-m. m, which includes a mounting information generating unit 206 that generates mounting operation information collectively indicating that each m is not mounted and outputs the generated mounting operation information to the SOH inserting unit 202. SOH insertion unit 202
After inserting the mounting operation information obtained from the mounting information generation unit 206 into a predetermined byte among the undefined bytes (see FIG. 5) in the RSOH or MSOH, the RSOH and the MSOH including the mounting operation information are multiplexed. The signal is sent to the high-speed transmission line as an STM-N high-speed signal.

On the other hand, as a receiving means, the high-speed signal interface unit 2 is provided with an RSOH terminal extracted from the STM-N high-speed signal input from a counterpart device having a similar configuration (not shown) through a high-speed transmission line by the SOH termination unit 203.
And the mounting operation information on the opposing device is extracted from the MSOH and from the MSOH, the non-mounted state of each of the plurality of low-speed signal interface units in the opposing device is recognized based on the mounting operation information, and the recognition result is output to the alarm processing unit 3. At the same time, based on the recognition result, an unmounted signal indicating whether or not each of the low-speed signal interface units in the opposing device is not mounted is generated to form a path with the unmounted low-speed signal interface unit in the corresponding opposing device. State identification unit 2 for outputting to any of low-speed signal interface units 1-1 to 1-m
07.

The alarm processing unit 3 includes a pointer processing unit 2
The alarm processing unit 301 collects alarms of the path AIS and the pointer abnormality detected at 05, and outputs a path alarm signal indicating the path abnormality, and the mounting state identification unit 207 determines the path alarm signal from the alarm processing unit 301. And a path alarm control unit 302 for controlling the issuance of a path alarm to the outside of the device based on the recognition result of the other device. More specifically, when the path alarm signal is obtained from the alarm processing unit 301, the path alarm control unit 302 refers to the recognition result regarding the opposing device from the mounting state identification unit 207 and determines whether the path alarm signal is When the path warning signal is for a path related to a low-speed signal interface unit that is not mounted in the device, the issuance of a path warning is prohibited, but only the path warning for a path in operation is issued.

Low-speed signal interface unit 1-1
1-m also notifies the external device (not shown) on the low-speed side transmission path connected to itself of the fact that the corresponding path is inactive, so that the mounting state identification in the high-speed signal interface unit 2 is performed. The SOH insertion unit 1 generates path non-operation information indicating that the corresponding path is non-operation based on the non-mounted signal from the unit 207.
03 is included. The SOH insertion unit 103 includes the path non-operation information generation unit 10
5, the path non-operation information obtained from RSOH or MS
After being inserted into a predetermined byte among the undefined bytes in the OH, the RSOH and the MSOH including the path non-operation information are inserted into the separated low-speed data signal, and transmitted to the low-speed side transmission path as an STM-M low-speed signal.

According to the multiplex transmission apparatus of the present embodiment having the above-described configuration, when an unnecessary low-speed signal interface unit is not mounted on an operating path, the path alarm corresponding to the unmounted low-speed signal interface unit is used. Issue and the spread to downstream devices can be prohibited.

[0028]

According to the multiplex transmission apparatus of the present invention, as a transmission operation, a plurality of low-speed signal interface units generate and output a mounting signal indicating that each of them is mounted. Each mounting signal for each interface unit is collected and included in the section overhead as mounting operation information. On the other hand, as a receiving operation, mounting operation information on the opposing device included in the section overhead removed from the high-speed signal by the high-speed signal interface unit. Is output to the alarm processing unit, and based on the mounting operation information, an unmounted signal indicating that each low-speed signal interface unit is not mounted in the opposing device is generated, and a corresponding plurality of low-speed signal interface units are generated. The alarm processing unit controls the issuance of a path alarm based on the mounting operation information on the opposing device, and the plurality of low-speed signal interface units perform their own operations based on the unmounted signal on each device. Some low-speed signal interface units are not implemented to generate path non-operation information indicating that the path formed with the mounted low-speed signal interface unit is non-operational and to include it in the section overhead. In the case where the low-speed signal interface unit is installed in the low-speed signal interface unit, it is possible to prohibit the issuance and propagation of the path alarm corresponding to the low-speed signal interface unit that is not mounted.
As a result, with respect to the path alarm, only the path alarm corresponding to the path in operation can be issued, so that the state of the system path can be determined only by confirming the alarm,
The user or maintenance person can easily perform maintenance and management without having to perform complicated maintenance work.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing a multiplex transmission device according to a conventional example.

3A and 3B are block diagrams illustrating a configuration example of a low-speed signal interface unit. FIG. 3A illustrates an STM-0 interface, and FIG. 3B illustrates an STM-n interface.

FIG. 4 is a block diagram showing a configuration example of a system using the multiplex transmission apparatus shown in FIG.

FIG. 5 is an ST applied to an embodiment of the present invention and a conventional example.
It is a figure showing the composition of an MN frame.

FIG. 6 shows an AU applied to an embodiment of the present invention and a conventional example.
FIG. 3 is a diagram illustrating a configuration of a pointer.

[Explanation of symbols]

 1-1 to 1-m Low-speed signal interface unit 2 High-speed signal interface unit 3 Alarm processing unit 101 SOH termination unit 102 Pointer processing unit 103 SOH insertion unit 104 Mounting information insertion unit 105 Path non-operation information generation unit 201 Multiplexing unit 202 SOH Insertion unit 203 SOH termination unit 204 Separation unit 205 Pointer processing unit 206 Mounting information generation unit 207 Mounting state recognition unit 301 Alarm processing unit 302 Path alarm control unit

Claims (3)

(57) [Claims] 1. A high-speed signal which is arranged between a plurality of low-speed side transmission paths and one high-speed side transmission path, multiplexes a plurality of low-speed signals from the plurality of low-speed side transmission paths, and inserts a section overhead to obtain a high-speed signal. While transmitting, the high-speed signal from the high-speed transmission line is separated from the high-speed signal after removing the section overhead, and a plurality of low-speed signals are output to any of the corresponding low-speed transmission lines. In addition, in a multiplex transmission device that performs a reception operation that issues a path alarm indicating a path abnormality based on the value of the pointer included in the separated low-speed signal, the transmission operation includes, for each of the plurality of low-speed side transmission paths While collecting each signal indicating the opening and closing as mounting operation information, while performing the operation of including the mounting operation information in the section overhead, the reception operation and The multiplex transmission device performs an operation of controlling the issuance of the path alarm based on mounting operation information on the opposing device included in the section overhead removed from the high-speed signal. 2. A plurality of low-speed signal interface units connected to a plurality of low-speed transmission lines, respectively, and a high-speed signal interface unit connected between the plurality of low-speed signal interface units and one high-speed transmission line And an alarm processing unit connected to the high-speed signal interface unit. As a transmission operation, the plurality of low-speed signal interface units respectively convert a plurality of low-speed signals from the plurality of low-speed side transmission paths into a plurality of low-speed signals. Output as a data signal, the high-speed signal interface unit multiplexes the plurality of low-speed data signals, inserts a section overhead, and outputs as a high-speed signal. The high-speed signal from the After removing the bar head, the low-speed data signals are separated into a plurality of low-speed data signals, and each low-speed data signal is output to any of a plurality of corresponding low-speed signal interface units. A multiplex transmission device that outputs the plurality of low-speed signals to the plurality of low-speed side transmission paths, and the alarm processing unit issues a path alarm indicating a path abnormality based on a value of a pointer included in the high-speed data signal. The transmission operation further includes the plurality of low-speed signal interface units each generating and outputting a mounting signal indicating that the plurality of low-speed signal interface units are mounted, and the high-speed signal interface unit includes: Collect each of the above mounting signals and use them as mounting operation information The high-speed signal interface unit is included in the section overhead, and as the reception operation, the high-speed signal interface unit extracts the mounting operation information related to the opposing device included in the section overhead removed from the high-speed signal, and based on the mounting operation information. And recognizes the unmounted state of each of the plurality of low-speed signal interface units in the opposing device, and outputs a recognition result to the alarm processing unit. A mounted unmounted signal indicating whether or not mounted is generated and output to any of the plurality of corresponding low-speed signal interface units, and the alarm processing unit is configured to output the path alarm based on the recognition result regarding the opposite device. Controlling the launch, said plurality Each of the high-speed signal interface units generates path non-operation information indicating that a path formed between itself and an unmounted low-speed signal interface unit in the opposite device is non-operation based on the non-mounted signal. A multiplex transmission apparatus for performing an operation to be included in the section overhead. 3. A first to m-th low-speed signal interface unit connected to each of m (m is a natural number) low-speed transmission lines through which STM-M (M is a natural number) low-speed signals are transmitted; A high-speed signal interface unit connected between the first to m-th low-speed signal interface units and one high-speed transmission line through which STM-N (N is the product of M and m) high-speed signals is transmitted; An alarm processing unit connected to the high-speed signal interface unit, wherein each of the first to m-th low-speed signal interface units performs termination processing of the STM-M low-speed signal as transmission means, thereby providing a section overhead. And a section overhead terminator for outputting a low-speed data signal including an AU pointer and a payload. The interface unit, the first
And a multiplexing unit for multiplexing a plurality of the low-speed data signals from the low-speed signal interface units to the m-th low-speed signal interface unit, and inserting a section overhead into the multiplexed signal to output the STM-N high-speed signal. And the high-speed signal interface unit as the receiving means includes the ST
A section overhead terminator for terminating an MN high-speed signal to output a high-speed data signal including an AU pointer and a payload by removing section overhead; and separating and processing the high-speed data signal into a plurality of low-speed data signals. A separation unit that outputs each low-speed data signal to any of the corresponding first to m-th low-speed signal interface units, wherein each of the first to m-th low-speed signal interface units outputs A section overhead insertion unit for inserting the section overhead to output the STM-M low-speed signal, wherein the alarm processing unit detects a path abnormality based on a pointer value of each AU pointer included in each of the plurality of high-speed data signals. A warning that issues a path warning In the transmission device, the first to m-th low-speed signal interface units each further include, as the transmission unit, a mounting information insertion unit that generates a mounting signal indicating that the first to m-th low-speed signal interface units are mounted and outputs the mounting signal to the high-speed signal interface unit. Wherein the high-speed signal interface unit includes a mounting information generating unit that collects the mounting signals for each of the first to m-th low-speed signal interface units and generates mounting operation information, and the section overhead insertion. The section includes the mounting operation information in a section overhead, and further includes, as the receiving means, the high-speed signal interface unit, wherein the mounting operation information related to the opposing device included in the section overhead removed from the STM-N high-speed signal. To extract the Recognizing the unmounted state of each of the plurality of low-speed signal interface units in the opposing device based on the mounting operation information, outputting a recognition result to the alarm processing unit, and outputting the recognition result to the alarm processing unit, And generating an unmounted signal indicating whether or not each of the low-speed signal interface units in the opposing device is not mounted on the opposite device and outputting the signal to any of the first to m-th low-speed signal interface units. A state identification unit, wherein the alarm processing unit includes a path alarm control unit that controls the issuance of the path alarm based on the recognition result regarding the opposed device, and the first to m-th low-speed signal interface units each include: Based on the mounted / unmounted signal, the unmounted low-speed signal A path non-operation information generation unit that generates path non-operation information indicating that a path formed between the interface unit and the interface unit is non-operation, and the section overhead insertion unit stores the path non-operation information in the section overhead. A multiplex transmission apparatus characterized in that the multiplex transmission apparatus includes: