KR20070060492A - The fault detection mechanism depending on on/off state of the protection switching in sonet/sdh transport - Google Patents

Abstract

A method and a device for detecting a fault by protection switching in SONET(Synchronous Optical NETwork)/SDH(Synchronous Digital Hierarchy) equipment are provided to enhance reliability for fault detection in an operator system or other devices by transmitting the fault detected in the SONET/SDH equipment to the operator system or other devices. Each fault detector(110) detects the fault from a signal input terminal(150) of an SONET/SDH interface(170) in real-time. Each fault controller(120) transfers the detected fault information to the operator system or other devices(130) if the detected fault information is over a predetermined threshold. A protection switching part(140) performs a protection switching service by using the fault detected in the fault detector if the detected fault information is not over the predetermined threshold. The protection switching part is at least one of 1+1, 1:1, 1+N, and UPSR(Unidirectional Path Switched Rings).

Description

Fault detection mechanism and method for on / off state of the protection switching in SONET / SDH transport}

1 is a block diagram showing a failure detection device with or without protection switching in SONET / SDH equipment according to the present invention

2 is a flowchart illustrating a process of a failure control apparatus according to an embodiment of determining whether a protection switching operation is present in the present invention.

* Explanation of symbols for main parts of the drawings

110: failure detection unit 120: failure control unit

130: operating system and other devices 140: protection switching unit

150: signal input terminal 160: internal communication system

170: SONET / SDH interface

The present invention relates to a failure detection method of a SONET / SDH equipment, and in particular, the failure information detected at the time of protection switching in a system that periodically monitors failure information from a hardware failure detection device and handles the failure is transmitted to the operating system and other devices. A reliable failure detection apparatus and method for determining whether to do so.

In the SONET / SDH (Synchronous Optical Network / Synchronous Digital Hierarchy) network, there is an increasing demand for bandwidth for fast data transmission and reliable quality of service. In line with this situation, SONET / SDH equipment such as Packet over SONET (PoS) and Ethernet over SDH (EoS) continue to be developed, and the importance of service recovery due to failure detection increases due to the high impact of failures in each equipment. It became.

Therefore, SONET / SDH equipment supporting the conventional reliable service performs a protection switching function to maintain the current service without loss when a fatal failure occurs. This protection switching function continuously monitors the condition and detects a condition that may affect the quality of service or service, so that the recovery can be performed while maintaining the minimum effect.

However, in the conventional failure detection, recovery is performed by minimizing the impact of the service due to the protection switching, but the failure affecting the protection switching causes another failure to be transmitted to the operating system and other devices before the protection switching operates. .

Accordingly, the operating system and the other device may determine that a temporary failure is a normal failure, which affects the service of the corresponding system.

Accordingly, the present invention has been made to solve the above problems, when detecting a failure in the SONET / SDH equipment, the operator system or other device by controlling the transfer of the failure detected by the failure detection device to the operator system and other devices It is an object of the present invention to provide an apparatus and method for detecting a failure due to the presence of protection switching in SONET / SDH equipment that can increase the reliability of failure detection.

Another object of the present invention is to determine whether or not to transfer the failure detected by the failure detection device to the operator system and other devices by determining the presence or absence of a protection transfer from the protective switching operation device when detecting a failure in the SONET / SDH equipment And providing a method.

In the SONET / SDH equipment according to the present invention for achieving the above object, the fault detection method with or without protection switching in the interface failure detection method of the SONET / SDH network, by performing a real-time failure detection on the interface failure Detecting information, determining whether the corresponding failure information has been processed according to protection switching; and if the determination result is processed, transmitting and logging only cause information without transferring the failure information to the operating system and other devices; If the determination result is not processed, the failure information is determined, and if the threshold is exceeded, the operation system includes a step of performing a failure processing.

Preferably, the failure information includes Loss of Signal (LOS), Loss of Frame (LOF), Alarm Indication Signal on Line (MS-AIS), Remote Defect Indication on Line (MS-RDI), Bit Error Ratio in excess of BERSF. the provisioned Signal Fail limit), Bit Error Ratio in excess of the provisioned Signal Degrade limit (BERSD), Alarm Indication Signal of Path (AU-AIS), Remote Defect Indication of Path (AU-RDI), Unequipped Path Signal on UNEQ the incoming fiber, AU-LOP (Loss of Pointer on path), GFP-OOS (Lost frame sync), GFP-CHEC (core Hec error), VCAT-GRPID (Group id error), VCAT-MFI (MFI unlock) , At least one of sequence number mismatch (VCAT-SEQM), not aligned before writing on path (VCAT-NAW), message CRC error (LCAS-MCRC), state machine fail (LCAS-SMFL), and LCAS-RXMST (Rx_MST). It is characterized by.

Preferably, the interface of the SONET / SDH network is STS_48L, STS_12L, STS_192L, STM_64, STM_16, VC3, VC4, STS_1L, STS_1P, STS_3L, STS_3cP, STS_12cP, STS_48cP, STS_192cP, STM_0, S_4_4__4_S_4 It is characterized by any one or more.

Preferably operating the SONET / SDH fault control device, initializing a register for fault detection consecutive counts and threshold calculations, reading fault information from the SONET / SDH interface, and whether the current equipment is configured to perform a protection switching operation. A first determination step of determining whether or not to set protection switching, and a second determination step of determining whether the currently detected obstacle is a disabled person detected immediately before the protection switching operation is performed by another failure. And if the failure is detected as a result of the second determination, transmitting a message to the operating system indicating that the current failure is not handled and that the service is continued by the protection switching operation. If it is not an obstacle or if the first judgment does not indicate that the protection transfer is set, A third judging step of judging whether the information signal is generated or released; a fourth judging step of judging whether or not the continuous occurrence of failures is zero; If the number of consecutive failures is 0, initializing the continuous failure release counts to zero and increasing the number of consecutive failures, and if the failures are not zero, increasing only the consecutive failures and the increased failure successive times. If the failure threshold is greater than the threshold value, the operating system notifies that the failure has occurred, if it is small, processing only the current failure information, and if the failure is not detected as a result of the third determination, the fifth determination step of determining whether or not the continuous number of failure release is 0 And, if the result of the fifth determination is that the number of continuous failure release times is 0, the failure release times are initialized to 0 and the failure release times are reset. If the failure successive number is not 0, increasing only the successive failure release times, and if the failure succession times is greater than a threshold, notifying the operating system that the failure has been released, and if only the current failure information processing Characterized in that it comprises a step.

Preferably, the register is characterized by consisting of at least one or more of the consecutive failures, consecutive failures, failure thresholds and failure thresholds.

In order to achieve the above object, a feature of a failure detection apparatus with or without protection switching in SONET / SDH equipment according to the present invention is a failure detection unit for detecting in real time that a failure is detected from a signal input terminal of a SONET / SDH interface; The fault control unit receives the detected fault information periodically and delivers it to the operating system and other devices only when a person with a disability exceeding a defined threshold and a disability detected by the disability detecting unit when the person does not exceed the defined threshold. It includes a protection switch that performs a service.

Preferably, the protective switching part is at least one of 1 + 1, 1: 1, 1 + N and UPSR (Unidirectional Path Switched Rings).

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments with reference to the accompanying drawings.

Referring to the accompanying drawings, a preferred embodiment of the apparatus and method for detecting a failure with protection switching in SONET / SDH equipment according to the present invention will be described below.

1 is a block diagram showing a failure detection device with or without protection switching in SONET / SDH equipment according to the present invention.

As shown in FIG. 1, a failure detection unit 110 for detecting in real time that a failure is detected from the signal input terminal 150 of the SONET / SDH interface 170 and the failure information detected by the failure detection unit 110 are periodically received. Disability control unit 120 for transmitting to the operating system and the other device 130 using the internal communication system 160 in the case of a disabled person exceeding a defined threshold, and the failure detection unit 110 in the case of a disabled person not exceeding the defined threshold. The protection switching service is configured to perform a protection switching service using a failure detected in the RX and transfer the result to the operation system and the other device 130 of the failure.

At this time, the protection switching unit 140 is composed of any one or more of 1 + 1, 1: 1, 1 + N and UPSR (Unidirectional Path Switched Rings).

With reference to the accompanying drawings, the operation of the failure detection apparatus with or without protection switching in the SONET / SDH equipment according to the present invention configured as described above will be described in detail.

2 is a flowchart illustrating a fault control apparatus process according to an embodiment of determining whether a protection switching operation is present, which will be described in detail as follows.

First, the SONET / SDH failure control device is operated (S10), and the register for continuous failure detection and threshold calculation is initialized (S20). In this case, the register is composed of consecutive failures, consecutive failures, failure thresholds and failure thresholds, and the failure thresholds and failure thresholds are values that should be reported to the operating system and other devices 130 of the failure. Each disability has a different value.

Subsequently, the failure detection unit 110 reads the failure information from the SONET / SDH interface 170 (S30), and determines whether the current equipment is set to perform the protection switching operation (S40).

At this time, if the result of the determination (S40) the protection switching is set, the information of the protection switching unit 140 is read from the protection switching unit 140 (S170). Then, it is determined whether the currently detected obstacle is a disabled person detected immediately before the protection switching operation by another obstacle (S180).

And if the determination result (S180), the failure due to the instantaneous protection switching operation, a message indicating that the current failure is a failure that is not handled by the failure control unit 120 and the service is continued by the protection switching operation (S190). ) Sent to the operating system and logging to the equipment (S200). Then, it is determined whether to continue the failure control unit 120 (S160), and if so, reads the failure detection device again (S30), otherwise terminates.

In addition, if the determination result (S180) is not an instantaneous failure of the protection switching and a failure due to a problem of the SONET / SDH interface 170, or if the determination result (S40) or the protection switching is not set, LOS (Loss of Signal, Loss of Frame (LOF), Alarm Indication Signal on Line (MS-AIS), Remote Defect Indication on Line (MS-RDI), Bit Error Ratio in excess of the provisioned Signal Fail limit (BERSF), BERSD (Bit) Error Ratio in excess of the provisioned Signal Degrade limit, Alarm Indication Signal of Path (AU-AIS), Remote Defect Indication of Path (AU-RDI), Unequipped Path Signal on the incoming fiber (UNEQ), AU-LOP (Loss of Pointer on path, GFP-OOS (Lost frame sync), GFP-CHEC (core Hec error), VCAT-GRPID (Group id error) VCAT-MFI (MFI unlock), VCAT-SEQM (Sequence number Mismatch), VCAT Whether or not signals such as NAW (not aligned before writing on path), LCAS-MCRC (message CRC error), LCAS-SMFL (State Machine Fail) and LCAS-RXMST (Rx_MST) are generated or released And (S50).

If the result of the determination (S50), if the failure occurs, it is determined whether the failure consecutive times is 0 (S60), and if this is the case, the successive failure release times are initialized to 0 (S70) and the failure successive times is increased (S80). ).

In addition, if the determination result (S60), if the continuous number of failures consecutive times is not 0, only the number of consecutive failures is increased (S80).

Subsequently, if the continuous number of failures is greater than the failure threshold X, after notifying the operating system that a failure has occurred (S140), the register of the failure detection apparatus is initialized to perform the current failure process for the next real-time failure processing (S140). In addition, when the number of consecutive failures is less than the failure threshold X, only the current failure information is processed (S150).

Then, it is determined whether to continue the failure control unit 120 (S160) to return to read the failure detection device to detect a new failure (S30).

In addition, if it is determined that the failure is not detected (S50), it is determined whether or not the continuous failure release count is 0 (S100), and when the failure release continuous count is 0, the failure release continuous count value is initialized to 0 (S110). Increase the number of consecutive releases (S120). In addition, if the determination result (S100), the failure release consecutive times is not 0, only the failure release consecutive times is increased (S120).

Subsequently, it is determined whether or not the continuous number of failure releases exceeds a threshold Y value (S130). If this is the case, the operating system is notified that the failure has been released (S140). After processing the current failure (S150), the failure controller 120 Ask whether to continue (S160).

In addition, if the determination result (S130), if not corresponding to the current failure information processing only (S150), if the failure control unit 120 will continue to read the failure detection device again (S30), otherwise the failure control device is terminated. .

As such, when a failure is detected in the conventional SONET / SDH interface 170, the failure control unit 120 processes the failure through the failure detection unit 110 and transmits the failure to the operating system and the other device 130. When the failure that passed through the detection unit 110 is processed by the protection switching unit 140 and does not need to be processed by the failure control unit 120, the failure control unit 120 transmits the failure information to the operating system and the other device 130. It will not be delivered.

Although the accompanying drawings of the present invention have been described above, it shows a flowchart of an embodiment of the present invention and does not limit the present invention. Therefore, anyone with this technical knowledge can improve various functions and the like without departing from the scope of the technical idea of the present invention.

As described above, in the SONET / SDH equipment according to the present invention, the apparatus and method for detecting a failure by the presence or absence of protection switching may be compared to a failure detection method and a failure to be recognized by the operating system and other devices as compared with the conventional failure detection method. The addition of a distinguishing function makes fault detection more reliable and allows the operator to analyze the exact cause of failure.

Claims (7)

In the interface failure detection method of a SONET / SDH (Synchronous Optical NETwork / Synchronous Digital Hierarchy) network, Determining whether failure information has been processed according to protection switching when real-time failure detection is performed on the corresponding interface to detect failure information; If the determination result is processed, transmitting and logging only the cause information without transferring the failure information to the operating system and other devices; If the determination result is not processed, the failure information detection method for failure detection by the presence or absence of the protection switching in the SONET / SDH equipment, characterized in that it comprises the step of notifying the operating system when the failure exceeds the threshold. The method of claim 1, The failure information includes Loss of Signal (LOS), Loss of Frame (LOF), Alarm Indication Signal on Line (MS-AIS), Remote Defect Indication on Line (MS-RDI), Bit Error Ratio in excess of the provisioned Signal Fail limit), Bit Error Ratio in excess of the provisioned Signal Degrade limit (BERSD), Alarm Indication Signal of Path (AU-AIS), Remote Defect Indication of Path (AU-RDI), Unequipped Path signal on the incoming fiber), AU-LOP (Loss of Pointer on path), GFP-OOS (Lost frame sync), GFP-CHEC (core Hec error), VCAT-GRPID (Group id error), VCAT-MFI (MFI unlock), VCAT -At least one of sequence number mismatch (SEQM), not aligned before writing on path (VCAT-NAW), message CRC error (LCAS-MCRC), state machine fail (LCAS-SMFL), and LCAS-RXMST (Rx_MST) Fault detection method with or without protection switching in SONET / SDH equipment. The method of claim 1, The SONET / interface of the SDH network are STS_48L, STS_12L, STS_192L, STM_64, STM_16, VC3, VC4, STS_1L, STS_1P, STS_3L, STS_3cP, STS_12cP, STS_48cP, STS_192cP, STM_0, STM_1, VC4_4c, VC4_16c, any one of the VC4_64c and STM_4 Method for detecting a failure by the presence or absence of protection switching in SONET / SDH equipment, characterized in that above. Operating a SONET / SDH fault control device and initializing a register for fault detection consecutive counts and threshold calculations; A first determination step of reading fault information from the SONET / SDH interface and determining whether the current equipment is set to perform a protection switching operation; A second determination step of determining whether the currently detected obstacle is a disabled person detected immediately before the protection switching operation by another failure, if the protection switching is set as the result of the first determination; If the failure is detected as a result of the second determination, transmitting a message indicating that the current failure is not handled and that the service is continued by the protection switching operation; A third judging step of judging whether a failure information signal is generated or released if the second judging result is not an instantaneous failure or if the first judging result does not set the protection switching; A fourth determination step of determining whether the number of consecutive failure occurrences is zero when the third determination result is failure; When the fourth determination result indicates that the consecutive failure occurrences are zero, initializing the failure release consecutive times to zero and increasing the failure occurrence successive times, and increasing the failure occurrence successive times only when the failure occurrence successive times is not zero; If the increased number of consecutive failures is greater than a failure threshold, notifying the operating system that a failure has occurred, and if less, processing only current failure information; A fifth judging step of judging whether or not the continuous number of failure releases is zero if a failure is not detected as the third judgment result; If the fifth determination result indicates that the successive release times are 0, the successive release times are reset to zero, and the successive release times are increased. If the successive release times are not 0, only the successive release times are increased. Steps, If the continuous number of failure release times greater than the threshold value notification that the failure is released to the operating system, if small, the current failure information processing method characterized in that the failure detection by the presence or absence of protection switching in the SONET / SDH equipment. The method of claim 4, wherein The register is a failure detection method according to the presence or absence of protection switching in the SONET / SDH equipment, characterized in that at least one or more of the consecutive failures, consecutive failures, failure thresholds and failure thresholds. A failure detection unit for detecting in real time that a failure is detected from a signal input terminal of the SONET / SDH interface; A fault controller which receives the detected fault information periodically and delivers it to an operating system and another device only when a disabled person exceeds a defined threshold value; And a protection switching unit for performing a protection switching service using a failure detected by the failure detection unit when the disabled person does not exceed the defined threshold. The method of claim 6, The protection switching part is 1 + 1, 1: 1, 1 + N and UPSR (Unidirectional Path Switched Rings) any one or more of the failure detection device by the presence or absence of protection switching in the SONET / SDH equipment.

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