07_OTA105210 OptiX NG-SDH Alarm and Performance Event ISSUE 1.02

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OTA105210 OptiX NG-SDH Alarm and Performance Event

ISSUE 1.02

HUAWEI TECHNOLOGIES CO., LTD. All rights reserved Page 2

Upon completion of this course, you will be able to:

Know the mechanism of SDH Alarm and

performance generation;

Analyze and process most of common alarm and

performance events.


Chapter 1 Generation of Alarm& PerformanceChapter 1 Generation of Alarm& Performance

Chapter 2 Alarm& Performance Event ClearingChapter 2 Alarm& Performance Event Clearing



1.1 Terminology 1.1 Terminology

1.2 1.2 Higher Order PartHigher Order Part

1.3 Lower Order Part1.3 Lower Order Part

1.4 Suppression Correlation between 1.4 Suppression Correlation between

SDH AlarmsSDH Alarms

1.5 Generation and Detection of SDH 1.5 Generation and Detection of SDH

Performance EventsPerformance Events


Terminology

SDHInterface cross-connect

unit

SDHInterface

PDH interface

Higher order part

Downlink signal flow

Downlink signal flow & Higher order partDownlink signal flow & Higher order part


Terminology

SDHInterface cross-connect

unit

SDHInterface

PDH interface

Lower order part

Uplink signal flow & Lower order partUplink signal flow & Lower order part

Uplink signal flow


Terminology

Two Common AlarmsTwo Common Alarms

AIS (Alarm Indication Signal)

Inserts the all “1”s signal into the lower level circuits,

Indicating that the signal is

unavailable. Common AIS alarms include MS_AIS, AU_AIS,

TU_AIS and E1_AIS.

RDI (Remote Defect Indication)

Indicates the alarm transferred back to the home station

from the opposite station after the opposite station has

detected alarms of LOS (loss of signal), AIS and TIM (trace

identifier mismatch). Common RDI alarms include MS_RDI,

HP_RDI and LP_RDI.



1.1 Terminology1.1 Terminology








A B C D E F G

STM-N Cross-connect Unit

SPISPI RSTRST MSTMST MSPMSP MSAMSA HPTHPT

Uplink signal Flow

Downlink signal Flow

SDHSDH Interface to Cross-connect Unit Interface to Cross-connect Unit

Alarms& Performance of Higher Order Part


Frame synchronizer& RS overhead processor

(RST)

MS overhead processor

(MST)

Pointer processor& HP overhead processor

(MSA, HPT)

LOS

LOF

B1 ErrA1,A2

B1

AIS

MS_AIS

B2 ErrK2B2

MS_REIM1

MS_RDIK2

“1” AIS

AU_AIS

AU_LOPH1,H2

H4B3 Err

J1

HP_SLMC2

“1”

HP_LOM

HP_TIMHP_UNEQ

HP_REI

HP_RDI

H1,H2

C2

B3

G1

G1

“1” XCS

STM-N

Optical Signal

Downlink signal flow Alarm report or returnSignal transfer point (Insert down

all "1"s signal)Alarm termination point

(Report to SCC unit)


Diagram of Alarm GenerationDiagram of Alarm Generation


Downlink Signal FlowDownlink Signal Flow

Frame synchronizer and RS overhead processor Optical receiving

Optical/electrical conversion (O/E) O/E module checks Optical signal (If no light in the input signal, optical

power excessively low or high or the code type mismatch, R_LOS alarm will be reported)

A1, A2 and J0 bytes detecting Search the framing bytes (R_OOF, R_LOF) Extract the line synchronous timing source J0 byte (J0_MM) Scramble

B1 byte detecting BIP-8 computing to check bit error (B1_SD, B1_EXC, SES, RSUAT) Process F1, D1 - D3 and E1 bytes



DownDownlink Signal Flowlink Signal Flow


K1 and K2 bytes detecting

SF and SD detection

Process D4 ~ D12, S1 and E2 bytes

MSP protection function

MS_AIS, MS_RDI

B2 byte detecting

BIP-24 computing to check bit error (B2_SD and B2_OVER)

M1 bytes (MS_REI)




Pointer processor and HP overhead processor H1 and H2 bytes detecting

Frequency and phase alignment Locate each VC-4 and send it to higher order path overhead processor Generate AU_AIS, AU_LOP

J1, C2, B3 and G1 bytes detecting J1 Bytes (HP_TIM) C2 Bytes (HP_UNEQ, HP_SLM) B3 bit error detecting (B3_SD, B3_OVER, SES, HVCUAT) H4 Bytes (For VC12 signal, HP_LOM) G1 Bytes (HP_RDI, HP_REI) F3, K3, N1 Bytes (Reserved)



UpUplink Signal Flowlink Signal Flow

Pointer processor and HP overhead processor

Generates N higher order path overhead bytes

J1, C2, B3, G1, F2, F3 and N1 Bytes

Return alarm to the remote end

HP_RDI (G1)

HP_REI (G1)

AU-4 pointers generating

Pointer processor generates N AU-4 pointers






Set multiplex section overhead (MSOH) Bytes

K1, K2, D4-D12, S1, M1, E2 and B2 Bytes

Return alarm to the remote end

MS_RDI (K2)

MS_REI (M1)




Frame synchronizer and RS overhead processor

Set regenerator section overhead (RSOH) Bytes

A1, A2, J0, E1, F1, D1-D3 and B1 Bytes

Frame synchronizer and scrambler scrambles STM-N

electrical signals

E/O











G H I J K

PDH InterfaceCross-connect Unit

HPAHPA LPTLPT LPALPA PPIPPI

Uplink signal Flow

Downlink signal Flow

PDH Interface to Cross-connect UnitPDH Interface to Cross-connect Unit

Alarms & Performance of Lower Order Part


PDH Physical InterfaceLower Order Path AdaptationHigher Order Path Adaptation& Lower Order Path Termination

E1 Interface

E1 Interface

Diagram of Alarm GenerationDiagram of Alarm Generation

(PPI)(LPA)(HPA, LPT)

LP_TFIFO

All “1”

LP_SLM

LP_UNEQ

V1,V2

H4

BIP 2

J2

TU_AIS

V5

HP_LOM

LP_TIMTU_LOP

LP_REI

LP_RDI

V5

V5

XCS

V5

V1,V2

LP_RFIFO

E1_AIS All “1” T_ALOS

E1_AISXCS

Downlink signal flow Alarm report or returnSignal transfer point (Insert down

all "1"s signal)Alarm termination point

(Report to SCC unit)



Downlink Signal FlowDownlink Signal Flow


V1, V2 and V3 bytes detecting

Demap the VC-4 into VC-12s

Pointers of all VC-12s are decoded

TU_AIS, TU_LOP

V5 Bytes detecting

LP_RDI( b8), LP_UNEQ, LP_SLM( b5-b7), LP_REI( b3)

BIP-2 computing to check bit error( b1-b2)

H4 Bytes detecting

HP_LOM

J2 Bytes detecting

LP_TIM



Lower Order Path Adaptation& PDH Physical Interface

Lower Order Path Adaptation

Recover data stream and the related clock reference signals

Detect LP_RFIFO alarm

PDH Physical Interface

Forming a 2048 kbit/s signal




Lower Order Path Adaptation& PDH Physical Interface

Lower Order Path Adaptation

Data adaptation

Detect LP_TFIFO alarm

PDH Physical Interface

Clock extraction and dada regeneration

Detect and terminate the T_ALOS alarm

Detect E1_AIS alarm




Higher Order Path Adaptation& Lower Order Path Termination

Lower Order Path Termination

Insert POH in the C-12 (C-12 to VC-12)

V5 byte (Insert "signal label" in the b5-b7, calculate BIP-2, set the result to the b1

and b2)

Higher Order Path Adaptation

Adapt VC-12 into TU-12

Map TU-12 into higher order VC-4



Difference between E3/E4 and E1 Alarm Signal

For E3 and E4 PDH services, the flow of signal processing is the same

as that of E1 PDH service But there are still some differences:

Same Type of Alarms with Different Names

2Mbit/s ： T_ALOS TU_AIS

34Mbit/s ： P_LOS E3_AIS

140Mbit/s ： EXT_LOS C4_R_LAISD/C4_T_LAISD

Path Overhead Bytes Used for Alarm& Performance Monitoring are

Different

2Mbit/s: V5 Byte

34Mbit/s, 140Mbit/s: B3, J1, C2 and G1 Bytes











R_LOS

R_LOF

R_OOF

AU_AIS AU_LOP B1_SD B2_SD

HP_TIM

HP_SLM HP_LOMHP_UNE

QB3_EXEC

B3_SD TU_AIS TU_LOP BIP_EXEC

LP_UNEQ LP_TIM LP_SLM BIP_SD

MS_RDI

HP_RDI

LP_RDI

Legend:

A B A suppress B

J0_MM MS_AIS B1_EXEC B2_EXEC

A1, A2 Bytes

RSOH, MSOH (Except A1,A2)

Suppression Correlation between SDH Alarms

Suppression Relationship








1.5 Generation and Detection of SDH1.5 Generation and Detection of SDH



Bit Error Generation MechanismBit Error Generation Mechanism

Notice: The Sequence of descramble& BIPNotice: The Sequence of descramble& BIP

Generation and Detection of SDH Performance

Mechanism: Bit interleaved parity (BIP)

Transmit end: The result of BIP is placed in the relevant bytes

of the next frame

Receive end: Compare the result of BIP with the bytes of the

next frame

B1: BIP8 for the regenerator section error monitoring function

B2: BIP24 for multiplex section error monitoring function

B3: BIP8 for monitoring the bit error performance of VC-4

V5: BIP2 for monitoring the bit error performance of VC-12


B1

B2

B3

V5

RSTMSTHPTLPT LPTHPTMSTRST

Error Detection and ReportError Detection and Report


Errors occurring in lower order path will not be detected in higher

order path, higher order bit errors will trigger lower order errors.


TermsTerms


Term Description

BE Errored block, in which one or more bits are in error.

BBE Background block error, it is an errored block occurring outside of the period of UAT and SES.

FEBBE Far end block of background error, it is a BBE event detected at the far end.

ES Errored second, it is a certain second with one or more errored blocks detected.

FEES Far end errored second, in which an ES event detected at the far end.

SES

Severely errored second, it is a certain second which contains 30% errored blocks or at least one serious disturbance period (SDP). Here, the SDP is a period of at least four consecutive blocks or 1ms (taking the longer one) where the error ratios of all the consecutive blocks are 10-2 or loss of signal occurs.


TermsTerms


Term Description

FESES Far end severely errored second, in which an SES event

detected at the remote end.

CSES Consecutive severely errored second, in which the SES

events consecutively occur, but last less than 10 seconds.

FECSES Far end consecutive severely errored second, in which a

CSES event detected at the far end.

UAS

Unavailable second, it is a period of 10 consecutive

seconds during which the bit error ratio per second of the

digital signal in either of the transmission directions of a

transmission system is inferior to 10-3 . These ten seconds

are considered to be part of unavailable time.



Mechanism

Adjust pointers as required in practice, so as to tolerate rate

asynchronization and phase difference of payload signals.

That is, perform pointer justification on information payloads

to make the payloads synchronous with the STM-N frame

Sort

Administrative unit pointer (AU_PTR)

Tributary unit pointer (TU_PTR)

PointerPointer JustificationJustification



H1 Y Y H2 F F H3 H3 H3 VC4

9

row

10………270 Column

91

Location:

Causation:

− Network is out of synchronization

Pointer justification state:

Name

Byte numbering and content of the fourth row in STM-1

frame Rate relation

7 8 9 10 11 12

Zero H3 H3 H3 Info Info Info Information = container

Positive H3 H3 H3 Stuffing Stuffing Stuffing Information< container

Negative Info Info Info Info Info Info Information> container

GenerationGeneration MechanismMechanism of AU Pointer Justificationof AU Pointer Justification


Causation:

− Transformed from AU pointer justification

− The system clock is not consistent with the received clock

− Pointer justification occurs at the upstream NE where the service passes


Remote detection:

− Occur at the local station, report at the remote station

Local detection:

− Generate at the local station, report locally

Generation Mechanism of TU Pointer JustificationGeneration Mechanism of TU Pointer Justification

Detection and Reporting of Pointer JustificationDetection and Reporting of Pointer Justification


Relationship between Alarms and Performance

Relationship

Alarm and Performance are belong to different levels. Alarm indicates

the fault of transmission, performance indicates the signal degrade of

transmission. If the value of performance is high than threshold it will

translate into alarm. For example bit error can translate into EXC alarm

then causes the traffic interrupt.

Functions of alarm and performance for bit error threshold crossing

Item Performance Event Alarm Event

Local end Remote end Local end Remote end

RS RSBBE - B1_OVER -

MS MSBBE MSFEBBE B2_OVER MS_REI

HP HPBBE HPFEBBE HPCROSSTR HP_REI

LP LPBBE LPFEBBE LPCROSSTR LP_REI


Question

Please describe the suppression correlation between SDH alarms?

What’s the mechanism of Pointer justification?

What’s the relationship between Performance event and Alarm?



Chapter 2 Alarm& Performance Event ClearingChapter 2 Alarm& Performance Event Clearing


Chapter 1 Chapter 1 Alarm& Performance Event ClearingAlarm& Performance Event Clearing

2.1 SDH Unit 2.1 SDH Unit

2.2 2.2 PDH UnitPDH Unit

2.3 Ethernet Unit2.3 Ethernet Unit

2.4 Cross-connect and timing Unit2.4 Cross-connect and timing Unit

2.5 SCC Unit2.5 SCC Unit


SDH Unit

R_LOF

Introduction:

− R_LOF alarm indicates “receive loss of frame”, critical alarm.

Probable Causes:

− The received signal attenuation is excessive.

− There is no frame structure in the signal from the opposite station.

− The receiver of the board fails.


SDH Unit

R_LOS

Introduction:

− R_LOS alarm indicates “receive loss of signal”, critical alarm.

− Probable Causes

There is a fiber cut.

− The line attenuation is excessive.

− The receiver of the board fails.

− The transmitter of the opposite station or line transmission fails.

− The XCS cards on the opposite station fails or is offline.


R_LOF/R_LOS Clearing Procedure:

SDH Unit

Step Action

1Check whether there is any higher-level R_LOS alarm on the T2000. Clear these higher-level alarms first.If the alarm does not clear, continue with the next step.

2Check whether the received optical power of the board reporting the alarm is normal. If yes, turn to Step 9.If not, continue with the next step.

3 Clean the fiber connector and the receiving optical interface of the board. If the alarm does not clear, continue with the next step.

4Check if the connection between local flange and the optical attenuator is correct, and if the attenuation value is too high. If there is a fault, clear it. Then, check if the alarm clears. If the alarm persists, continue with the next step.

5Check if the transmitting optical power of the opposite station is normal. If not, replace the line board. If yes, clean the fiber connector of the opposite station.


R_LOF/R_LOS Clearing Procedure:

SDH Unit

Step Action

6

If the alarm persists, check if the connection between local flange and the optical attenuator of the opposite station is correct, and if the attenuation value is too high. If there is a fault, clear it. Then, check if the alarm clears. If the alarm persists, continue with the next step.

7Check the fiber. If there is a problem, clear it. Then, check if the alarm clears. If the alarm persists, continue with the next step.

8Replace the line board reporting the alarm at the local station. If the alarm does not clear, continue with the next step.

9Replace the GXCS, EXCS, UXCS, or XCE on the local station. If the alarm does not clear, continue with the next step.

10Replace the line board on the opposite station. If the alarm does not clear, continue with the next step.

11 Replace the GXCS, EXCS, UXCS, or XCE on the opposite station.


SDH Unit

B2_OVER

Introduction:

− B2_OVER alarm indicates “indication of excessive B2

errors in the multiplex section”, major alarm.

Probable Causes :

− The received signal attenuation is excessive.

− The fiber end is not clean.

− The fiber connector is connected incorrectly.

− The receiver of the local station fails.

− The transmitter of the opposite station fails.


SDH Unit

B2_OVER Clearing Procedure

Step Action

1Check whether there are any higher-level alarms, such as R_LOS, R_LOF or B1_EXC on the T2000. Clear these higher-level alarms first.If the alarm does not clear, continue with the next step.

2Check whether the working temperature of the equipment is too high. If yes, lower the temperature.Then, if the alarm persists, continue with the next step.

3Replace the line board reporting the alarm at the local station.If the alarm does not clear, continue with the next step.

4Replace the GXCS, EXCS, UXCS, or XCE on the local station.If the alarm does not clear, continue with the next step.

5Replace the line board on the opposite station.If the alarm does not clear, continue with the next step.

6 Replace the GXCS, EXCS, UXCS, or XCE on the opposite station.


SDH Unit

MS_AIS

Introduction:

MS_AIS alarm indicates “multiplex section alarm indication”,

which is a major alarm.

Probable Causes

The opposite station transmits the MS_AIS signal.

The GXCS, EXCS, UXCS, or XCE of the opposite station fails.

A fault occurs in the receiver of the board.

:


SDH Unit

MS_AIS Clearing Procedure

Step Action

1

Check whether the corresponding line board reports R_LOS or

R_LOF alarm on the T2000. If there is a R_LOS or R_LOF, clear

it.

Then, check if the alarm clears. If the alarm persists, continue with

the next step.

2Reset or replace the line board on the local station.

If the alarm does not clear, continue with the next step.

3Reset or replace the line board on the opposite station.


4Reset or replace the GXCS, EXCS, UXCS, or XCE on the

opposite station.


SDH Unit AU_AIS

Introduction:

AU_AIS alarm indicates “AU alarm indication”, which is a

major alarm.

Probable Causes:

The opposite station sends AU_AIS.

The transmitter of the opposite station fails.

The receiver of the local station fails.


SDH Unit

AU_AIS Clearing ProcedureStep Action

1

Check whether there are any higher-level alarms, such as R_LOS, R_LOF, B1_EXC or

B2_OVER, on the T2000. Clear these higher-level alarms first. If the alarm does not

clear, continue.

2Check whether the NE is under the protection switching. If yes, remove the fault. If the

alarm does not clear, continue.

3Check whether the service configuration of the NE is correct. If not, modify the incorrect

configuration. Then, check whether the alarm clears. If not, continue.

4 Use the alarm analysis and loopback methods to find the NE on which a fault occurs.

5Replace the line board reporting alarms on the faulty NE. If the alarm does not clear,

continue.

6 Replace the XCS board on the faulty NE. If the alarm does not clear, continue.

7 Replace the line board of the opposite station. If the alarm does not clear, continue.

8 Replace the GXCS, EXCS, UXCS, or XCE board on the opposite station.


SDH Unit

BD_STATUS

Introduction:

BD_STATUS alarm indicates “board offline”, major alarm.

Probable Causes:

The board is not inserted.

The board is not fully inserted.

The mailbox fails.


SDH Unit

BD_STATUS Clearing Procedure

Step Action

1 Check whether the corresponding board is in the slot.

2 Remove and re-insert the board.


3 Replace the board.


4 Replace the backplane of the local station.


SDH Unit

Other Alarms

Name Description

MS_RDI Multiplex section remote defect indication, minor alarm.

MS_REI Multiplex section remote error indication, warning

AU_LOP AU loss of pointer, minor alarm.

HP_TIM Higher order path tracking identification mismatch, minor alarm.

HP_SLM Higher order path signal identification mismatch, minor alarm.

HP_RDI Higher order path remote defect indication, minor alarm.

HP_REI Higher order path remote error indication, minor alarm.

HP_UNEQ No loading error in the higher order path, minor alarm.

IN_PWR_ABN Input power abnormal, major alarm.

LASER_SHUT Laser shut down, major alarm.

LOOP_ALM Loop alarm, minor alarm.

COMMUN_FAIL Board serial port communication failure, major alarm.



2.1 SDH Unit2.1 SDH Unit






PDH Unit

TU_AIS

Introduction:

− TU_AIS alarm indicates “TU alarm indication”, which is a

major alarm.

Probable Causes

− There are errors in configuration data.

− The corresponding path at the opposite station fails.

− There is a higher level alarm.

− The cross-connect board fails.


PDH Unit

TU_AIS Clearing Procedure

Step Action

1Check whether there are any higher-level alarms, such as R_LOS, R_LOF or HP_SLM, on the T2000. Clear these higher-level alarms first.


2Check whether the NE is in the protection switching state. If yes, remove the fault causing the switching.

Then, check whether the alarm clears. If not, continue with the next step.

3Check whether the service configuration of the NE is correct. If not, modify the incorrect configuration.

Then, check whether the alarm clears. If not, continue with Step 4.

4Replace the alarm reporting tributary board.


5 Replace the GXCS, EXCS, UXCS, or XCE.


PDH Unit

TU_LOP

Introduction:

− TU_LOP alarm indicates “TU Loss of Pointer”, which is

a major alarm.

Probable Causes:

− The interface between the tributary board and the cross-

connect board fails.

− There are errors in configuration data.


PDH Unit

TU_LOP Clearing Procedure

Step Action

1

Check whether there are any higher-level alarms, such as R_LOS, R_LOF or HP_SLM,

on the T2000. Clear these higher-level alarms first.


2

Check whether the NE is in the protection switching state. If yes, remove the fault

causing the switching.

Then, check whether the alarm clears. If not, continue with the next step.

3Check whether the service configuration of the NE is correct. If not, modify the incorrect

configuration.

4If the alarm persists, replace the alarm reporting tributary board and then view whether

the alarm is removed.

5 If the alarm persists, replace the GXCS, EXCS, UXCS, or XCE.


PDH Unit

T_ALOS

Introduction:

− T_ALOS alarm indicates “E1 interface loss of analog

signal”, which is a major alarm.

Probable Causes:

− No E1 service is accessed.

− The output port of the E1 interface on the DDF side is

disconnected or loosened.

− The input port of the E1 interface at the local station is

disconnected or loosened.

− Board failure.

− Cable fails.


PDH Unit

T_ALOS Clearing Procedure

Step Action

1Check whether the corresponding path of the tributary board reports the TU_AIS or TU_LOP alarm on the T2000. If yes, clear the alarm.

Then, check if the T_ALOS clears. If not, continue with the next step.

2Perform self-loop (hardware inloop) for the path reporting the alarm at the DDF. If the alarm clears, the fault lies in the equipment of the opposite end. Remove the fault.

Then, check if the alarm clears. If not, continue with the next step.

3Perform self-loop (hardware inloop) for the path at the interface board. If the alarm clears, the fault lies in the signal cable connection. Remove the fault.


4Perform inloop for the path on the T2000. If the alarm clears, the fault lies in the interface board. Remove and then re-insert or replace the interface board.


5 Replace the service processing board.


PDH Unit

Other Alarms

Name Description

LP_RDI Lower order path remote defect indication, minor alarm.

LP_REI Lower order path remote error indication, minor alarm.

NO_BD_SOFT No board software, critical alarm.

PS Protection switching is initiated, major alarm.

UP_E1_AIS 2M signal alarm indication, minor alarm.

DOWN_E1_AIS E1 down signal alarm, minor alarm.

ALM_SUBCARD_ABN Find the fault of sub-board, major alarm.

BD_STATUS Board offline, major alarm.

COMMUN_FAIL Serial port communication failure, major alarm.









Ethernet Unit

ALM_SUBCARD_ABN

Introduction:

− ALM_SUBCARD_ABN alarm indicates “find the fault of sub-

board”, which is a major alarm.

Probable Causes:

− The interface board does not match the processing board.

− Clearing Procedure:

Step Action

1Check whether the interface board is inserted correctly. If not, re-insert the

board.

2If the alarm persists, check the configuration of the corresponding service

processing board on the T2000. Modify the incorrect configuration.


Ethernet Unit

Other AlarmsName Description

AU_AIS AU alarm indication, major alarm.

ETH_LOS Ethernet Receive loss of input signal, critical alarm.

PROTOCOL_MM Encapsulation protocol types mismatched, critical alarm.


BD_STATUS Board not in position alarm, major alarm.


LOOP_ALM Loop alarm, minor alarm.









Cross-connect and timing Unit

APS_FAIL

Introduction:

− APS_FAIL alarm indicates “APS protection switching

failed”, which is a major alarm.

Probable Causes:

The multiplex section protection (MSP) parameters of the

nodes are incorrect.

The MSP parameters of the nodes are lost.



Clearing Procedure

Step Action

1

Check whether the MSP parameters of the nodes are correct. If not, modify

the incorrect parameters.


2Check whether the MSP protocol is normal. If not, stop and then restart the

protocol.



APS_INDI

Introduction:

− APS_INDI alarm indicates “APS protection switching

indication”, which is a major alarm.

Probable Causes:

− MSP switching is initiated.

− Clearing Procedure

Step Action

1For an MSP ring, this alarm indicates that MSP switching is initiated.

Remove the fault.

2

For a non-ring MSP network, this alarm indicates that the APS protocol is

initiated abnormally. Check whether the MSP parameters of the nodes are

correct. If not, modify the incorrect parameters.



EXT_SYNC_LOS

Introduction:

− The EXT_SYNC_LOS alarm indicates “loss of external synchronous source”, which is a minor alarm.

− The external clock source is lost.

Probable Causes:


Step Action

1Check whether the equipment that provides the external clock works

efficiently.

2Check whether the external clock cable is connected correctly and whether

the connectors are in good contact. If there is a fault, remove it.



LTI

Introduction:

− LTI alarm indicates “loss of synchronization source”, which is a major alarm.

Probable Causes:

Non S1 mode:

− There is a fiber cut (the line clock is traced).

− No external clock source is input (the external clock is traced).

− The synchronization source is set as non-retrieve, is blocked or is set

incorrectly.

S1 mode:

− There is a fiber cut.

− The free-run mode is in active.

− The synchronization source is set incorrectly.



Clearing Procedure:

Step Action

1View the clock source traced by the NE. Clock source could be external clock source, line clock source, and tributary clock source.

External clock source

2Check whether the output signal of the external clock device is normal. If not, replace the device.Then, check if the alarm clears. If the alarm persists, continue with the next step.

3Check whether the external clock input mode is proper (2 MHz or 2 Mbit/s). If the mode mismatches each other, correct the setting.Then, check if the alarm clears. If the alarm persists, continue with the next step.

4Check whether the external clock input impedance is proper ( 75-ohm or 120-ohm). If the impedance mismatches each other, correct the setting.Then, check if the alarm clears. If the alarm persists, continue with the next step.

5Check whether the clock input cable is connected correctly. If not, connect the cable correctly. Then, check if the alarm clears. If the alarm persists, continue with the next step.

6 Reset or replace the GXCS, EXCS, UXCS, or XCE.



Clearing Procedure:

Step Action

Line clock source

7

Check whether the corresponding line board reports R_LOS alarm through the T2000.

If there is a R_LOS alarm, clear it.

Then, check if the alarm clears. If the alarm persists, continue with the next step.

8

Reset or replace the line board.


9 Reset or replace the GXCS, EXCS, UXCS, or XCE.



Other Alarms

Name Description

BUS_ERR Bus error, major alarm.

CLK_NO_TRACE_MODE Clock entering into non-tracing running mode, minor alarm.

S1_SYN_CHANGE Clock reference source change in S1_Mode, minor alarm.

SYN_BAD Synchronization source deteriorated, minor alarm.

SYNC_C_LOS Synchronization source level loss, warning.












SCC Unit

NESTATE_INSTALL

Introduction:

− NESTATE_INSTALL alarm indicates “NE in install state”,

which is a critical alarm.

Probable Causes:

− The NE is under installation.


Step Action

1 Correct the configuration data and re-send the data.


SCC Unit

WRG_BD_TYPE

Introduction:

− WRG_BD_TYPE alarm indicates “wrong inserted board

type”, which is a minor alarm.

Probable Causes:

− A wrong board is inserted.

− There are errors in the board configuration.

− Clearing ProcedureStep Action

1 Check whether the board is of the right type. If not, insert a right one.

2If the alarm persists, check whether the board configuration is correct. If not,

modify the incorrect configuration.


SCC Unit

Other Alarms

Name Description

HARD_BAD The HARD_BAD alarm indicates “hardware fails”, critical alarm.

NESF_LOST Lost of one nesoft, critical alarm.

NODEID_MM Multiplex section node ID mismatch, Major alarm.

POWER_ABNORMAL Power is abnormal, major alarm

POWER_FAIL Power failure, major alarm




NE2

NE4

NE3 NE1 NE5SNCP

E

E

E

E

W

W

W

W

W2 W

Case of 2 fiber SNCP ring with no protection chain. NE1, NE2, NE4, NE5 is OSN 3500 equipment, NE3 is OSN 2500 REG.

NE5 NE1 NE2 NE4

T1 ： 1-16 T1 ： 1-16

T2 ： 1-16 T1 ： 1-16

T2 ： 1-16 T2 ： 1-16

T1 ： 1-15 T3 ： 1-15

All of the traffic are unidirectional

1#-16#VC12

17#-32# VC12

33#-48#VC12

49#-63# VC12

Exercise


Exercise

PQ1 (NE1)

W

E

NE5NE4NE3NE2NE1Card\NE

- MS_RDI - - -

- - R_LOS MS_AIS -

- - - -

If the Tx fiber between NE2 and NE3 is broken, please fill in the blank. If no alarm please fill in with “-” .

A. R_LOS; B. MS_AIS; C. MS_RDI; D. TU_AIS; E. LP_RDI;


Generation of Alarm& Performance

Alarm& Performance Event Clearing

Case of Ring with Chain

Summary

www.huawei.com

Thank You

Documents

07_OTA105210 OptiX NG-SDH Alarm and Performance Event ISSUE 1.02