KR100221528B1 - Test access method of synchronous transmission network - Google Patents

Abstract

The present invention relates to a synchronous transmission network using a circuit distribution device as a central node. When the network is composed of only single-station devices as in the conventional transmission network, the present invention provides a method for testing a signal state of a currently serving channel when there is doubt. We used an inefficient method of seeing the status of the signal returned by manually looping back the signal from the other station through the contact or by cutting off the signal at the input terminal of the other station and attenuating the signal. The present invention for solving the above problems is the apparatus in the non-cutting test state and the cutting test state by using the pseudo-random pattern test signal generation and transmission function and the test signal reception function and detection function according to each signal level applied in the synchronous transmission Function Blocks and Functions of Synchronous Transport Network Nodes of Other Stations Automatically set up transmission paths to extract and aggregate path fault information and performance information so that connection status between multiple, branch, distribution and multiplexing functions or adjacent functions involved in channel end-to-end connection can be checked. By automatically finding and isolating the point of failure of transmission path or deterioration of performance, it is possible to determine the failure or non-connection and wrong connection in circuit distribution system based on test access function. Improve performance of transmission path and reliable information service on the network by analyzing performance information on the adjacent transmission node connected to the outside of distribution device, path of end-to-end connection, cause of failure and location of failure, etc. By providing, the transmission network can be used efficiently.

Description

Test access method of synchronous transmission network

The present invention utilizes pseudorandom pattern test signal generation and transmission function and test signal reception function and detection function according to each signal level applied in synchronous transmission. The transmission path is automatically set by the functions of the synchronous network nodes of the office to extract the fault information and the performance information of the path, and then aggregate and multiply, branch, distribute, and multiplex the functions involved in the channel end-to-end connection. It can check the connection status between functions and automatically find and isolate the point that causes the failure or performance degradation of the transmission path.

Therefore, based on the test access function, it is possible to determine the failure or unconnected or incorrect connection of the path in the circuit distribution apparatus, and to determine the path of the adjacent transmission node device connected to the outside of the circuit distribution apparatus and the path of the end and end connections. It is an object of the present invention to provide a comprehensive information by analyzing the performance information, the cause of the failure and the location of the failure, and to efficiently use the transmission network by improving the performance of the transmission path in the network and providing reliable information service. .

The main application field of the present invention is a line distribution device that has a function of terminating synchronous and asynchronous signals and resetting the path of a broadband distribution channel, and provides a state monitoring or termination and reconnection function for digital transmission sections and signal paths. Is a test access method in a transmission network applied as shown in FIG.

In case that the signal status of the channel currently being serviced is in doubt, if the signal status of the currently serviced channel is configured like a conventional transmission network, a method of testing the signal is to manually loop back the signal from the other station for the currently serviced signal. We have used inefficient methods to see the state of the signal, or to cut off the signal at the input terminal of the other station, and to attenuate the signal through the attenuation function.

The manual test access method of the transmission network and the transmission apparatus described above could be possible in a transmission network composed of a conventional coaxial cable having fewer lines.

However, in modern transmission networks consisting of tens of gigabytes of optical fiber, manual channel-level testing is not practical.

In addition, in a synchronous transmission network, when a synchronous transmission network including a broadband circuit distribution device that plays a key role in a synchronous transmission network and serves as a transmission network node that reconfigures a transmission path connected to the network is connected to a path during path switching by the circuit distribution device. Automated test access is essential for checking status or recovering from failures.

In addition, as the transmission network becomes more complex, unmanned station operation is required. In this case, an automated test access method is required even more when a pre-installation operation test or a remote loopback test is required by the automated test access method.

The automated test access method of the present invention is applied as a method of the initial transmission test of the component network when a large capacity device such as the broadband distribution line device is installed in the transmission network.

1 is a block diagram of a device in a new synchronous transmission network to which the present invention is applied.

2 is a block diagram of a circuit distribution apparatus to which the test access function of the present invention is applied.

3 is a block diagram of a test access unit of the present invention.

Figure 4a is a test access path configuration by the cut test in the circuit distribution apparatus itself of the present invention.

Figure 4b is a test access path configuration by the cut test in the circuit distribution apparatus itself of the present invention.

Figure 5a is a test access configuration (remote cutting test) for the whole section of the sub-network centered on the circuit distribution apparatus according to the present invention.

Figure 5b is a test access configuration (remote cutting test) for the line side of the sub-network centered on the circuit distribution apparatus according to the present invention.

5c is a diagram illustrating a test access configuration (remote cutting test) for an east line of a sub network centered on a circuit distribution system.

* Explanation of symbols for main parts of the drawings

1000: Central Office (CO) 1100: Branch-mounted equipment (ADM)

1200: Circuit Distribution Device (DCS) 1210: Receiver

1220: front end switch section 1230: space switch section

1240: rear switch 1250: transmitter

1260: test access unit 1261: DS3 test signal generation / detection unit

1262: C3 signal mapping unit 1263: VC32 formation and detection unit

1264: AU pointer forming unit 1265: AU front and rear time switch

1266: DS1 test signal generator / detector 1267: VC1n formation and detector

1268: TU pointer forming unit 1269: TU front and rear time switch unit

1300: station device 1400: source node device

1500: relay node device 1600: destination node device

1700: test management

The automated test access method proposed by the present invention is applied.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of a circuit distribution apparatus to which the test access function to which the present invention is applied is applied.

In view of the above configuration, the receiver 1210 which connects the light to perform electrical conversion and performs pointer processing to synchronize with the reference clock, the shear time switch unit 1220 that performs the low / high speed signal distribution switch, and the space switch unit 1230, a post-end time switch unit 1240, and a transmitter 1250 for converting the switched time switch into an optical signal and outputting the same, so that the test access unit 1260 has a front-rear end-time switch function. It is connected to the space switch unit 1230 and operates.

3 is a diagram illustrating a test access path by a non-cutting test in the circuit distribution apparatus itself of the present invention.

In order to configure the apparatus of the automated test method, a test access signal generator and a detector as shown in FIG. 3 are required.

In addition, the transmission level of the test pattern to be used for the configuration test of the environment, that is, the type of transmission path to be tested is determined by the device management system or the transmission network operation management system of the circuit distribution apparatus 1200, and the types are C11, C12, C32, etc., is a method to increase the efficiency of the test. After searching the maintenance information of the equivalent level with respect to the type of the channel where the failure or performance has occurred, the test transmission path for the highest transmission level is established.

The signal of the pseudorandom pattern is generated in a unit mounted for the test access function of the circuit distribution apparatus 1200. The circuit distribution apparatus performs the distribution functions of the AU32, TU11, and TU12 units, so that the DS1N, DS1E and Therefore, since the actual path change of the DS3 signal is performed, the test signal is mapped to the corresponding virtual container as follows according to the bit unit synchronization method of the asynchronous signal in the existing synchronous multiple device.

In addition, it is possible to connect the BER tester with the external DSn signal unit to support the DSN-level upstream AIS signal insertion function accommodated in the existing synchronous multiple devices or to maintain the test between the domestic systems for the system initialization or special purpose. It shall be possible to avoid limiting the type of test signal.

The test pattern having transmission rates of DS1N and DS1E selects a pseudo random binary sequence signal having a length of 2 ¹⁵ -1 as recommended by ITU-T.

The BS1E is synchronized to C12 and then multiplexed to TU12 via VC12, and the DS1N test signal 1266 is input to the test transmission path through the multipath to C12-VC12-TU12 / C11-VC11-TU11.

The test signal 1261 of the DS3 transmission rate uses a pseudorandom pattern having a length of 2 ¹⁵ -1 and is multiplexed to AU32 via C32-VC32.

As described above, the AIS signal of each signal level and the signal generated from the BER tester can also be adopted as the test signal.

Fig. 4 is a block diagram of a test access path by the cut test in the circuit distribution apparatus of the present invention.

The above configuration applies the non-cutting test method and the cutting test method.

The non-crunching test monitors the state of the path overhead detected by the receiver 1210 in order to determine the exact cause of the path inside the circuit distribution apparatus 1200 of the normally suspected channel or the problem signal. At the same time, the overhead of the signal output from the transmitter 1250 is monitored to find a fault point.

This is divided into both sides around the space switch to which the test access unit 1260 is connected in the device as shown in Figure 4a divided into 'ga' section and 'I' section, which is a problem in the space switch unit 1230 in the device Bridge the signal on the path and supply the same signal to the test access section to determine the state of the 'A' section.

If there is no error in the information monitored by the receiver 1210 to know the state of the 'ga' section, and there is an error in the information detected by the test access unit 1260, it is determined that there is a problem in the path of the 'ga' section. do.

However, if there is no error in the 'a' section, it is determined that there is a problem in the path of the 'b' section.

After determining the performance and failure of the corresponding path in the line distribution apparatus 1200 itself by the non-cutting test as described above, the state of the 'a' or 'b' section is determined and separation of the failure point is easy.

The results of the above non-cutting test are reported to the operator of the circuit distribution apparatus 1200, and when the operator wants a more accurate result or the condition of the path in question is very bad, the cut test access method is used. do.

In the above-described device cutting test access method, as shown in FIG. 4B, a service switch 1230 is cut by inserting a payload of an original signal by cutting a service previously provided and inserting a test pattern generated in the test access unit 1260. After transmitting through), and transmits to the 'b' section shown in the figure, and loops back the output signal of the transmitter 1250 and inputs it to the test access section through the 'ga' section to find out the exact location of the failure.

Through the above truncation test, the exact location of the fault can be determined and its fault separation must be serviced to start the signal again.

Before performing the truncation test, service interruption of the corresponding signal is performed at the source node and the destination node along the path.

The message is transmitted using a data communication channel (DCC) or a data communication network (DCN), which is a communication method in a current transmission network.

The test access unit 1260 analyzes pseudorandom pattern signal error information of the payload together with the monitoring information of the path overhead, and obtains the status information of the corresponding path and reports it to the device operator.

Based on the test result report data, the device operator determines whether a person with a disability is present in the device itself or a person with a disability outside the device and reports on a path in which the self-disability occurs.

In addition, when it is determined that the failure is external to the device, it is reported to the network manager of the sub network centered on the circuit distribution apparatus 1200 to perform the test procedure in the sub network.

5a, 5b, and 5c show the configuration of the remote test access unit 1260, which is a cutting test method in a sub network by the operation of the network manager.

The above items are divided into two sections, namely, 'west line' and 'east line', and the sub network centering on the circuit distribution device 1200 is tested for each section. For the paths generated, the entire section through each connected node is tested.

Under the above structure, the necessary functions of the circuit distribution apparatus 1200 include a manager 1600 that manages a sub network in the device, so that the path connection point information of the sub network, the status information of the path, and each node necessary for test management are provided. Management through a data communication channel (DCC) or a data communication network (DCN).

5A is a block diagram of a test access for all sections of a sub-network centered on a circuit distribution apparatus according to the present invention.

According to the above configuration, it is a method of setting and testing a path of a sub network centered on the circuit distribution apparatus 1200 and a test path from the source node apparatus 1300 to the destination node apparatus 1500.

In this way, the test results for the entire route from 'west track' to 'east track' are obtained.

The report of the results tested at each node is transmitted through the data communication channel or data communication network.

5B is a block diagram of a test access unit 1260 for a line side of a sub network centered on a circuit distribution apparatus according to the present invention.

In the above configuration, a test path is set and tested for the 'west line' of the line distribution device 1200 from the source node unit 1300 in the path of the sub-network centering on the circuit distribution device 1200.

5C is a diagram illustrating a test access configuration for the east line of the sub network centered on the circuit distribution apparatus 1200.

The test access configuration is a method of setting and testing a test path for an 'east line' from a circuit distribution apparatus 1200 to a destination node in a path of a sub network centered on the circuit distribution apparatus 1200.

The paths of the sub-network centering on the circuit distribution apparatus 1200 are divided by the above three methods, and the test signals generated by the test access unit 1260 are inserted to form a path through a space switch in the device. Deliver the test signal.

When the destination node is a circuit distribution unit, the space switch unit 1230 in the device of the destination node device 1500 loops back a signal to the source node device 1300 by a distribution function to find a failure state.

When the destination node device 1500 passes through the relay node device 1400, the relay node device 1400 may bypass the signal by the operation of the network manager.

At this time, the test results collected from the corresponding paths at each node are transmitted to the circuit distribution apparatus 1200 through the data communication channel or the data communication network, and the test manager 1600, which is a function in the device, of the sub network. By accurately determining the overall path status, it is possible to determine the cause of the failure, to identify the cause of the failure, and to isolate the failure, thereby improving the reliability of the communication service and quickly recovering from the failure.

When the circuit distribution device to which the automated test access method as described above is configured as the central function of the synchronous transmission network, the state check in the device and the test management of the function blocks of the device can be performed.

The above results in constructing a convenient and reliable device and transmission network that cannot be compared with the conventional manual test method.

In addition, by using the test access function of the circuit distribution apparatus, end-to-end connection tracking for an arbitrary path and multiple, branching, and distribution functions of transmission nodes connected to the path are identified, and thus the failure or performance of the transmission path is prevented. It becomes possible to isolate the point which causes a fall.

In addition, when the large-scale line distribution device or station equipment is installed in the synchronous transmission network, the test access method described above for the initial transmission test on the component network can save time and cost and improve the stability of the device.

As a result, by applying the test access method, the basis for determining the cause and location of the fault based on the accurate path tracking of the transmission path, the initial test of the transmission path, and the accurate performance information of the transmission path are provided. It can improve the failover and survivability of the transport network.

Claims (8)

An optical signal is connected to a receiver to perform electrical conversion by performing optical processing, and to process a pointer to a reference clock, a front time switch unit, a space switch unit, a rear switch unit, and the switched time switch to perform a low speed / high speed signal distribution position. In the test access method in a synchronous transmission network having a space switch unit for converting and outputting and the test access unit connected to the space switch unit having the front and rear end time switch function, the test is a non-cutting test method and a cutting test The non-crunching test may be performed in such a manner that the state of the path overhead detected by the receiver 1 may be determined in order to determine the exact cause of the path in the circuit distribution apparatus of a normally suspected channel or a problem signal. The fault point by monitoring the overhead of the signal output from the transmitter 5 at the same time The process of searching for and separating the two sides of the space switch to which the test access unit 6 is connected to the 'ga' section and 'b' section and the path of the problem in the space switch unit 3 in the device Bridge the signal and supply the same signal to the test access section to determine the state of the 'ga' section, and the information monitored by the receiver 1 to know the state of the 'ga' section there is no error and the test access section If there is an error in the detected information, the process of determining that there is a problem in the path of the 'a' section, and if there is no error in the 'a' section, the process determines that there is a problem in the 'b' section. After determining the performance and the failure of the corresponding path in the circuit distribution device itself by the non-disconnection test, such as the process of separating the failure point and the state of the 'A' or 'B' section, and The results of the initial cut test are reported to the operator of the circuit distribution system, and the cut test access method is used to fundamentally find out when the operator wants a more accurate result or the condition of the path in question is bad; After cutting the service in the apparatus and inserting the test pattern generated in the test access unit 3 into the payload of the original signal and passing it through the space switch unit 3, and transmits to the 'B' section shown in the figure Looping back the output signal of (5) and inputting it to the test access unit through the 'a' section to find the exact location where the failure occurred; and in the test access unit 6 together with the monitoring information of the path overhead, Analyzing the pseudo random pattern signal error information to obtain the status information of the corresponding path and reporting it to the device operator; In the process of reporting the path of self-disability by judging whether the disability is in the device itself or the outside of the device based on the test result report data, and when it is determined that the failure is external to the device, it focuses on the line distribution device. And a step of reporting to a network administrator of a sub-network to perform a test procedure in the sub-network. The test access method according to claim 1, wherein the signal distribution is monitored by bridging to a test access unit through a switch distribution function without disconnecting the signal service to be monitored in the circuit distribution apparatus. The method of claim 1, wherein the input / output is cut in the circuit distribution apparatus to insert a test signal generated by the test access unit, loop the inserted signal to the input / output, and divide the two signals into two sections to find fault points step by step. Test access method of synchronous transmission network. 2. The apparatus of claim 1, wherein the circuit distribution apparatus to which the test access function is applied is configured as a central function of a synchronous transmission network, and thus the status of the device and the fault separation and the transmission path and the functional blocks of the apparatus in association with adjacent node devices on the transmission network. Test access method for a synchronous transmission network, characterized in that for the test management. The test access method according to claim 1, wherein the test signal is looped back through a switch distribution function when the destination node is a circuit distribution device. 2. The test access method according to claim 1, wherein the network constructed in the above configuration is divided into east and west directions with respect to the circuit distribution device to enable a test on the foreground path and a test on the half path. . The test access method according to claim 1, wherein a test result message between nodes is provided and transmitted through a DCC or a DCN with a test manager for test management of the configured transmission network. The test access method according to claim 1, wherein the test access function is applied to the transmission test between the device itself and the adjacent nodes when the circuit distribution apparatus or the station apparatus is initially installed in the synchronous transmission network.