JPH04358429A - Path monitoring system - Google Patents

Abstract

PURPOSE:To specify a faulty section if a fault occurs in a section where the monitoring is not carried out between the devices or in other sections in a path monitoring system which monitors the communication state of a signal path set in a device or between the devices. CONSTITUTION:A monitoring bit inserting part 1 is provided to insert a correct monitoring bit to a main circuit 6 of an input part at the relevant time point together with a path monitoring part 2 which monitors the monitoring bit via the circuit 6, a path monitoring bit reinserting part 3 which reproduces a monitoring bit similar to that of the part 1, and a selector part 4 which detects the monitoring bit passed through the circuit 6 at a path detecting part 2, transmits the signal of the circuit 6 as it is if a fault is detected, and then selects the monitoring bit of the part 3 and sends it to the following circuit 6 if no fault is detected. Thus the part 4 decides to transmit the original monitoring bit to the following stage as it is or to transmit the monitoring bit inserted to the part 3.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a path monitoring system for monitoring the state of a signal path within a communication device or between devices. With the development of the data society in recent years, the importance of communication devices is increasing, and highly reliable devices and transmission paths are required. For this reason, reliability is improved by monitoring the signal path within the device or between devices, and when a failure occurs in a certain section of the route, that section is switched to a backup line. For this reason, path monitoring has become extremely important.

0002

[Prior Art] Figure 4 shows a connection configuration diagram of a conventional bus monitoring system.
Shown below. FIG. 4A shows a method in which a path monitoring bit is inserted and detected for each section, and path monitoring is performed independently for each section. FIG. 4B shows a method in which a monitoring bit is added at an input point into the route, and monitoring is performed at an arbitrary point within the route according to the monitoring bit.

In the figure, 21 is a monitoring bit insertion unit that can insert the correct monitoring bit at that time, and 22 is a path detection unit that can insert the monitoring bit inserted by the monitoring bit insertion unit 21. 26 is a main circuit that performs monitoring, and refers to a circuit or cable within the device. Furthermore, thick lines indicate signal flows, and dotted lines indicate separations between monitoring sections.

[0004] Portions A, B, C, and D surrounded by dotted lines each include a main circuit 26. For example, the main circuit of A is an interface circuit that converts signals between 64 KHz and 8 Mhz, and the main circuits of B and C are It consists of a buffer circuit that uses a time switch circuit to check timing discrepancies and converts time slots.The main circuit of D is an interface circuit that converts signals between 8Mhz and 64KHz, and connects input terminals and output terminals. Performing data input/output. Each main circuit 26 is connected to A to D by a cable or a transmission path, and a transmission signal from the input terminal side is transmitted as a digital signal to the output terminal side via the main circuit. A monitoring bit inserting section 21 inserts a monitoring bit into each frame of the digital signal, and each path detecting section 22 detects the monitoring bit passing through the main circuit, thereby monitoring failures in the main circuit 26 and the transmission path.

[0005]

[Problem to be Solved by the Invention] In the method shown in FIG. 4(a), the sections a, b,
The transmission path portions c and d are not monitored at all, although only slightly. In addition, in the method shown in Fig. 4(b), monitoring is performed without interruption from the input point to the output point, but if a failure occurs in an arbitrary section B, an abnormality is detected, but the subsequent sections C and D are Regardless of whether it is normal or abnormal, it will be detected as abnormal. Therefore, if a fault occurs in multiple sections, it is impossible to identify other faulty sections unless the faulty section closest to the input is restored.

[0006] The present invention does not create sections where no monitoring is performed as in the method shown in FIG. The purpose of the present invention is to provide a path monitoring method that does not make it impossible to identify faulty sections.

[0007]

[Means for Solving the Problems] A diagram of the principle configuration of the present invention is shown in FIG. In the figure, 1 is a monitoring bit insertion section,
The correct monitoring bit at that time is inserted into the main circuit 6 of the input section. Reference numeral 2 denotes a path detection unit which monitors the monitoring bits passed through the main circuit 6. 3 is a path monitoring bit reinsertion unit that reproduces monitoring bits similar to the monitoring bit insertion unit 1; 4 is a path detection unit 2 that detects the monitoring bits that have passed through the main circuit 6;
A selector section is shown that passes the signal of the main circuit 6 as is if there is no failure, and selects the monitoring bit of the path monitoring bit reinsertion section 3 and sends it to the next main circuit 6 if there is a failure. 6 is a main circuit for monitoring, which refers to a circuit or cable within the device. Furthermore, thick lines indicate signal flows, and dotted lines indicate separations between monitoring sections.

This method basically employs the same monitoring method as the conventional method shown in FIG. 4(a), but the monitoring bit insertion section 1 is connected to the main circuit 6 of the input section, and the ,
A path detection section 2, a path monitoring bit reinsertion section 3, and a selector section 4 are connected after the main circuit 6, and a path monitoring bit reinsertion section 3 similar to the monitoring bit insertion section 1 is provided immediately after the detection point.
The selector unit 4 is configured to select whether to send out the original monitoring bit as it is or to send out the monitoring bit inserted by the path monitoring bit reinsertion unit 3.

[0009]

[Operation] A time chart of the monitoring bit of the present invention is shown in FIG. In the figure, ■ is input data of 8KH per frame.
'0' or '1' is inserted into the monitoring bit insertion position for each z. 3 is data that has passed through the main circuit 6, and the monitoring bit insertion position has been shifted. ■ is a monitoring bit inserted into the path detection unit 2, and '0' or '1' at the monitoring bit insertion position
monitor. (2) performs an EXOR operation on the monitoring bit (2) of the data that has passed through the main circuit 6 and the monitoring bit (2) of the path detection unit 2, and if they are the same, it sends out '0', and if they are not the same, it sends out '1'. If they are the same, the monitor bit from the main circuit is sent as is from the selector unit 4 as shown in ■; if not, the monitor bit from the path monitor bit reinsertion unit 3 is sent out by controlling the selector unit 4 as shown in ■. is reinserted.

Therefore, even if a failure occurs in a certain section, the selector section 4 allows the path monitoring bit reinsertion section 3 to insert the correct monitoring bit at that point.
It becomes possible to monitor the subsequent section.

[0011]

Embodiment FIG. 3 shows a connection configuration diagram of an embodiment of the present invention. The figure shows a device consisting of N packages.
All input/output points are provided with a path monitoring detection section, an insertion section, and a selector section, and the selector section can be freely selected for each point. Further, the input side of the first package is provided with a mask portion so as not to perform path monitoring.

In the figure, 10 is the first package;
20 is the second package, 30 is the Nth package, 11 is a monitoring bit insertion section, 12 is an input path detection section, 13 is a path monitoring bit reinsertion section, 14 is an input selector section, and 15 is a mask. 16 is a main circuit, 17 is an output selector section, and 18 is an output path detection section.

Naturally, the monitoring bit is not input to the first package 10, so the mask section 15 is set so that the input path detection section 12 does not detect it, and the input selector section 14 also inserts the monitoring bit at that point. choose to do so. The other output sides of the main circuit 16 are monitored as described above. Since the input and output sides of each package are monitored, it is possible to isolate whether the problem is within a package or between packages. If a failure occurs at any point, the input selector unit 14
to switch to the currently correct monitoring bit. This makes it possible to deal with failures occurring in multiple locations.

In the above embodiment, monitoring is performed only within one device, but when combined with a device having the same monitoring method, the mask portion 15 is released and the selector portion 14 also selects the one in front. By doing so, it is possible to easily monitor paths between devices with exactly the same accuracy for more than one device.

[0015]

[Effects of the Invention] As explained above, according to the present invention, even if a failure occurs in a certain section, it is possible to insert the correct monitoring bit at that point, so that the subsequent sections can be monitored. This has the effect of making it possible to identify the fault location even if a fault occurs at multiple locations.In addition, by doing as shown in the example, path monitoring between devices can be performed not only within the device. This has the effect of being easily and easily possible, and greatly contributes to improving the reliability of such communication devices.

[Brief explanation of drawings]

[Figure 1] Principle configuration diagram of the present invention

[Figure 2] Time chart of the present invention

[Figure 3] Connection configuration diagram of the embodiment

[Figure 4] Connection configuration diagram of conventional example

[Explanation of symbols]

1, 11, 21 Monitor bit insertion part 2, 12, 18, 22 Path detection section 3,13 Path monitoring bit reinsertion unit 4, 14, 17 Selector section 6, 16, 26 Main circuit 10, 20, 30 package 15 Mask part

Claims (2)

[Claims] 1. In a path monitoring method for monitoring the state of a signal path within a device or between devices in communication, a monitoring bit insertion unit (1) inserts the correct monitoring bit at that time into a main circuit (6) of an input unit. ), a path monitoring section (2) that monitors the monitoring bits passed through the main circuit (6), and a path monitoring bit reinsertion section (3) that reproduces the same monitoring bits as the monitoring bit insertion section (1). The path detection unit (2) detects the monitoring bit that has passed through the main circuit (6), and if there is no failure, the signal from the main circuit (6) is passed through as is, and if there is a failure, the path monitoring bit reinsertion unit (3) detects the monitoring bit that has passed through the main circuit (6). ) and sends it to the next main circuit (6).The selector part (4) selects whether to send the original monitoring bit backwards as it is or to send it to the next main circuit (6). A path monitoring method characterized by selecting whether to transmit the monitoring bit inserted by the reinsertion unit (3). 2. In the above configuration, the input side includes a monitoring bit insertion section, a path detection section, and a selector section, and the path detection section is provided with a mask section, so that path monitoring between devices without remaining within the device is performed. 2. The path monitoring method according to claim 1, wherein: