JPS58105654A - Detecting system for line state - Google Patents

Abstract

PURPOSE:To precisely detect troubles generated in an opposite device by comparing a pattern in a receiving frame from the opposite device with an inherent pattern in the self-device and detecting that the information of the self-device is folded by the opposite device. CONSTITUTION:A frame receiving circuit 5 receives a receiving frame from an opposite communication device, and when frame synchronization is confirmed, applies the received information to a selecting circuit 4 and informs a timing signal to a comparator 8. The comparator 8 compares the inherent pattern NID of the device in the received information with the inherent pattern NID of the self-device set up in an inherent pattern setting circuit 3, and when both the patterns coincide each other, informs a coincidence signal to a data decoding circuit 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a line state detection method for detecting the presence or absence of a failure in a partner device between communication devices connected via a transmission path.

When communicating between communication devices via a transmission path, communication may become impossible due to a failure in a device other than the own station. In such cases, it is necessary to isolate where the failure occurred. It is necessary to investigate. In particular, if there is a fault in the partner device, it is desirable to be able to detect this early. However, there has been no known means for clearly detecting the presence or absence of a failure in such a partner device. Therefore, when a failure occurs, try disconnecting the own device, the transmission path, and the other device each time while setting various situations.
The location of the failure had to be determined.

The present invention aims to solve these problems in the prior art, and its purpose is to provide a means for setting a pattern unique to the communication device within the communication device, and to set this unique pattern in the transmission frame. The device is equipped with means for comparing the pattern in the frame received from the other device with the unique pattern of the own device, and the information of the own device is folded and transmitted by the other device based on the comparison result. The object of the present invention is to provide a method that can detect a failure in a destination device by knowing that the device is being sent back.

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

FIG. 1 shows an embodiment of the format of a transmission frame in the line state detection method of the present invention. In the figure, 5YNC is a frame synchronization pattern necessary for synchronizing transmitted frames in a communication device. Further, DATA is inter-device transfer information transferred between communication devices. The NID is a device-specific pattern specific to the communication device, and is used to know the state of the other device in the line state detection method of the present invention.

FIG. 2 shows the configuration of an embodiment of the line state detection method of the present invention. In the figure, 1 is a data generation circuit, 2
3 is a frame generation circuit, 3 is a unique pattern setting circuit, 4 is a selection circuit, 5 is a frame reception circuit, 6 is an OR circuit, 7 is a frame transmission circuit, 8 is a comparison circuit, 9 is a data decoding circuit, 10 is a fault detection circuit These are the communication device 20
included in.

In FIG. 2, a data generation circuit 1 generates inter-device transfer information DATA based on data to be transferred to a partner device, and inputs it to a frame generation circuit 2.

Further, the unique pattern setting circuit 3 is set with a unique pattern for the communication device, and the unique pattern NI of the device is set.
D is generated and input to the frame generation circuit 2. The frame generation circuit 2 multiplexes the inter-device transfer information DATA and the device-specific pattern NID and sends it to the selection circuit 2 as transmission information.
At the same time, the selection circuit 4 is notified of a timing signal indicating the delimiter of the transmission information. Reception information from the frame reception circuit 5 is further applied to the selection circuit 4, and the selection circuit 4 selects the transmission information from the frame generation circuit 2 and the reception information from the frame reception circuit 5 according to the switching instruction signal from the OR circuit 6. Select one of them and input it to the frame transmitting circuit 7. The frame transmitting circuit 7 adds a frame synchronization pattern 5YNC for frame synchronization generated within its own circuit to the information received from the selection circuit 4, and sends it to the other communication device as a transmission frame.

When the communication frame reception circuit 5 receives the reception frame from the partner communication device and establishes frame synchronization, it applies the reception information to the selection circuit 4 as described above, and also applies the reception information and reception information to the comparison circuit 8. A timing signal indicating the delimiter of the received information extracted from the frame is notified. The comparison circuit 8 compares the device-specific pattern HID in the received information with the device-specific pattern NID of the own device set in the device-specific pattern (turn setting circuit 3), and when they match, data decodes the matching signal. Notify the circuit 9 O The data decoding circuit 9 receives the received information via the comparison circuit 8, and does not decode the data when it receives a match signal from the comparison circuit 8, but does not decode the data when it receives a match signal from the comparison circuit 8. If the received information is not received, the device-to-device transfer information DATA part of the received information should be deciphered, and the remote switching instruction has been issued from the other device to the effect that the received information should be sent back to the other device. generates a remote switching instruction signal and inputs it to the OR circuit 6.

Further, the fault detection circuit 10 detects the presence or absence of a fault within its own device, and when a fault occurs, generates a fault detection signal and inputs it to the OR circuit 6.

As a result of such table control, if frames are being transmitted and received normally with the other device, the device-specific (NID) of the own device will not be received in the received frame. No coincidence signal is generated from the comparison circuit 8, and it can therefore be detected that the other device is normal. Also, on the other party's device, the information sent from the own device is 11.
When the signal is being looped back, a matching signal is generated from the comparison circuit 8, so that it can be known that the signal is being looped back.

The data generation circuit 1 can send a remote switching instruction to the other device as inter-device transfer information DATA. Therefore, when it is determined that the partner device is in the callback state based on the occurrence of a match signal from the comparison circuit 8, it is determined whether the remote switchover instruction described above is given or not. It is possible to check whether or not reversal is being performed. Fault detection circuit 1
No. 0 instructs the selection circuit 4 to switch when there is a failure in the own device, thereby causing a call back within the own station in the event of such a failure. Furthermore, it is also possible to detect the occurrence of a failure in the transmission path due to the loss of frame synchronization in the frame receiving circuit 5.

Furthermore, by adding a separate check code to the transmission frame and transmitting it, the frame receiving circuit 5 detects an error in the check code in the frame received by the other device, thereby detecting the occurrence of a failure on the transmission path. Is possible.

As described above, according to the line state detection method of the present invention, means for setting a pattern unique to the communication device is provided in the communication device, and this unique pattern is superimposed at a predetermined position in a transmission frame. By providing a means to compare the pattern in the frame sent and received from the other device with the unique pattern of the own device, the information of the other device is known that the information of the own device is returned by the other device. It is extremely effective because it can reliably detect failures.

Note that the line status detection method of the present invention is not limited to the other party's equipment, but as long as the information received at the time of failure can be simply folded back and returned as is, the detection method of the present invention can be applied to the other party's equipment. It is possible to detect the presence or absence of a failure in the device.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the format of a transmission frame in the line state detection method of the present invention, and FIG. 2 is a block diagram showing the configuration of an embodiment of the line state detection method of the present invention. 1... Data generation circuit, 2... Frame generation circuit,
3... Unique pattern setting circuit, 4... Selection circuit, 5
...7L/-A receiving circuit, 6...OR circuit, 7...
・Frame transmission circuit, 8... Comparison circuit, 9... Data decoding circuit, 10... Fault detection circuit, 20... Communication device patent applicant Fujitsu Ltd.

Claims (1)

[Claims] In a communication device that communicates with each other in the same frame format via a transmission path and loops back received frames and sends them out when a failure occurs in the device, a means for setting a pattern unique to the device, and a method for setting a pattern unique to the device. means for superimposing the pattern at a predetermined position of a transmitted frame, and means for comparing the pattern at the predetermined position in the received frame and the unique pattern of the own device and generating a match signal when they match, A line state detection method characterized in that occurrence of a failure in a partner device is detected by generation of the matching signal.