1 © NOKIA CT6042en version 1/ 08.07.2002 / PMa

Alarm MonitoringAlarm Monitoring

2 © NOKIA CT6042en version 1/ 08.07.2002 / PMa

Objectives

After completing this module, the participant should be able to:• Explain how to identify alarm situations within the network and how

to outline the procedures used to handle new active alarms. In addition, explain how to interpret alarm information in order to classify the alarm severity.

• Explain how to analyse alarm information in order to identify the affected element and also outline the techniques and commands used to conclude the possible effect on the network service.

• Based upon the knowledge gained about the affected element and using alarm history information with basic system commands, outline how it is possible to conclude the possible reason for the alarm and identify procedures to handle alarms.

• Explain a follow-up procedure used to determine that an alarm situation is closed and that the fault has not re-occurred. In addition, outline any reporting procedures that maybe necessary (based upon the operator's model or the remedy trouble ticketing system).

3 © NOKIA CT6042en version 1/ 08.07.2002 / PMa

Detecting faults in the network can be seen from different points

of view

Alarm flowTraffic & Signalling

MSCHLR

NetAct

RNC

MGW

BS

CustomerComplaints

AlarmsTestResult

Reports

Data from other systems

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Organisation of a network used in monitoring

External system

E.g. Transmission IP network

Global Network MonitorCentralised alarm database

Allocate work to regional office

Field engineers

Regional people

Downtownsouth

Maintenance regions

Downtown North

SMSCSCPSMS

NetActRegionalNetworkMonitor

Nomansville

Filter

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Life cycle of an alarm in the NetAct

Activealarm

Activealarm

Cancelledalarm

Cancelledalarm

Cancelledalarm

Normal situation

Alarm triggers

Acknowledged

Problem is fixed

Alarm is cancelledby network element

Alarm is cancelledby network element

Alarm activates again in network element

Acknowledged

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Alarm States and Data Inconsistencies

Active AlarmIn Network Element

Active Alarm in NMS or NetAct(Unacknowledged)

Cancel Alarm in NMS(Not acknowledged)

Cancel events are NOT sent to the Network Element from the NMS

Active AlarmIn Network Element

Alarm Cancelledin Network Element

Cancel event to NMS or NetAct

Alarm CancelledAcknowledged

Fault resolvedMost alarms automatically cancel at the network element

NMSNetAct

DX200IPA2800 DCNDCN

Resolve the Fault

Alarm event to NMS or NetAct

Acknowledge Alarm in NMS(Unacknowledged)

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Handling alarming situations in the

network

Unable tosolve intime limit

Network cancels alarm once fault is fixed

CanNOC fix the

fault?

Take correctiveaction

Locatethe fault

Identifythe fault

Alarm

Situationescalated/ assigned

no

yes

Fault fixed

Assess theeffect on service

Classifythe fault

Follow up and close the fault

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Using the NetAct tools to monitor the network

• Location of fault?• Impact on service?• Classification of fault?• Corrective course of action?

Object changescolour in top leveluser interface

Drop the object intothe alarm history tosee condition andacknowledge

Alarm appears in themonitor. Double-clickto see more information and acknowledge

or

More informationin manual page

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Broken link between the BTS/WBTS and BSC/RNC (as seen

from the NetAct)

When the connection between a BTS and BSC is broken, the BSC generates alarms indicating a broken PCM connection.

When a sector is unable to carry any traffic or signalling, then alarm 7767 is always generated.

Use the alarm manual to gain more reasons for the cause of the alarm.

The most critical alarms

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Using Traffica to monitor the network

Alarm window

MSC Traffica

Alarm appears in the monitor. Double click to see alarm description and cancel the alarm.

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When a link is lost, several alarms are generated from

different elements

BSC/RNCCN

HLR

BTS/WBTS

Alarms

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Alarm classification in the Nokia network

Type of alarm Colour in NetActType of alarm Colour in NetAct Severity of alarmSeverity of alarm

*** Red Critical: There is a fault that will effect the service.

** Orange Major: There is a potential situation that may result in a fault that will effect the service.

* Yellow Minor: There is either a small problem in the network, or an indication of an abnormal situation.

Warning None The network will generate a message whenever something happens.

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Classifying fault location based on element and location

Business Area

Shopping Area

Rural Area

RNC

OSS SS

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Identifying the effect on service

Site

Site

Site

Packet Data Services Voice Services

BSC / RNC

MSC / 3G MSC

SGSN / 3G-SGSN

Site BTS

WBTS Site BTS WBTS

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The state of radio network objects

and effect on service

2G: MSC / SGSN

3G: 3G-MSC / 3G-SGSN

BSC

RNC WBTS

BTS

CNCN RANRAN BSBS

MMLZEEI

NEMUObjectBrowser

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The state of signalling links and effect on service

2G: MSC

3G: 3G-MSC

BSC

RNC WBTS

BTS

CNCN RANRAN BSBSZNEL

ZNEL

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The state of PCN signalling and effect on service

2G: SGSN

3G: 3G-SGSN

BSC

RNC WBTS

BTS

CNCN RANRAN BSBS

MMLZFWO

WebBrowser

2G: SGSN

3G: 3G-SGSN

BSC

RNC WBTS

BTS

CNCN RANRAN BSBSCNCN RANRAN BSBS

MMLZFWO

WebBrowser

MMLZFWO

WebBrowser“Voyager”

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The state of PCN signalling between SGSN and HLR

2G-SGSN/MSC

3G-SGSN

BSC

RNC WBTS

BTS

CNCN RANRAN BSBSHLRHLR

MMLZNET

WebBrowser

2G-SGSN/MSC

3G-SGSN

BSC

RNC WBTS

BTS

CNCN RANRAN BSBSHLRHLR

MMLZNET

WebBrowser

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Example of fault prioritisation

Severity of problem Severity of problem Impact on serviceImpact on service Response Response time scaletime scale

• High priority Major loss of service ASAP

• Medium priority Service-affecting problem 1 hour

• Low priority Non-service affecting problem Working hours

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Scope of problem

• Does it effect different parts of the system, other than the element in question? (e.g. BTS transmission problems)

Depth of problem

• The technical ability needed to fix the problem(that is, a system expert is needed)

Time needed

• Does the monitoring personnel have the time to find and fix the problem?

Scope of authority

• Is the monitoring personnel allowed to make any changes or fixes

Determining a course of action

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Escalation process

Create logor ticket

Is thesituationcritical

Alarm escalated

Contact engineer

2nd line orspecialist

Create logor ticket

Recoveryprocedures

Contact on-call engineer

Is itnormalhours

yesno

yes

no

Fault locatedand effect on service identified