114180656 B11 GSM Quality of Service Traffic Load Monitoring

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BSS B11 GSM Quality of Service & Traffic Load Monitoring - Page 1

All Rights Reserved Alcatel-Lucent 2010

All Rights Reserved A lcatel-Lucent 2010

GSM B11BSS B11 GSM Quality of Service

& Traffic Load Monitoring

STUDENT GUIDE

TMO18096 D0 SG DEN I1.0 Issue 1

All rights reserved Alcatel-Lucent 2010Passing on and copying of this document, use and communication of its contents not

permitted without written authorization from Alcatel-Lucent


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BSS B11 GSM Quality of Service & Traffic Load MonitoringGSM B11

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Terms of Use and Legal Notices

Switch to notes view!1. Safety WarningBoth lethal and dangerous voltages may be present within the products used herein. The user is strongly advised not to wear

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The equipment used during this course may be electrostatic sensitive. Please observe correct anti-static precautions.

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without notice.

3. Copyright

This document contains information that is proprietary to Alcatel-Lucent and may be used for training purposes only. No other use or

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All rights reserved Alcatel-Lucent 2010

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Blank Page




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Course Outline

About This CourseCourse outline

Technical support

Course objectives

1. Topic/Section is Positioned HereXxx

Xxx

Xxx

2. Topic/Section is Positioned Here






1. B11 GSM QoS Monitoring

1. Introduction 3JK12191AAAAWBZZA

2. Indicators Overview 3JK12192AAAAWBZZA

3. Call Establishment 3JK12193AAAAWBZZA

4. Communication Phase 3JK12194AAAAWBZZA

5. Handover Indicators 3JK12195AAAAWBZZA

6. Directed Retry Indicators 3JK12196AAAAWBZZA

7. RMS Indicators 3JK12197AAAAWBZZA

8. Traffic Indicators 3JK12198AAAAWBZZA

9. Case Studies 3JK12199AAAAWBZZA

10. Annexes 3JK12200AAAAWBZZA


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Course Outline [cont.]




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7

Course Objectives


Welcome to BSS B11 GSM Quality of Service & Traffic Load Monitoring

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

During this training, the participant will learn how interpret counters and indicators of the Alcatel

BSS System, in NPO and in a protocol analyzer (K12).

By the end of the course, the participant will be able to interpret :

- Global indicators, in order to assess the general quality of the network

- Detailed indicators, in order to detect / identify / locate the main malfunctions

- Handover indicators, in order to quantify efficiency and reason of HO

- Directed retry indicators, in order to quantify efficiency of directed retry - RMS indicators to ease radio optimization and fault detection

- Traffic indicators, in order to detect/predict overload and compute adequate cell dimensioning as

well as to understand how RTCH resources are used in the network


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8

Course Objectives [cont.]




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9

About this Student Guide

Switch to notes view!Conventions used in this guide

Where you can get further information

If you want further information you can refer to the following:

Technical Practices for the specific product

Technical support page on the Alcatel website: http://www.alcatel-lucent.com

Note

Provides you with additional information about the topic being discussed. Althoughthis information is not required knowledge, you might find it useful or interesting.

Technical Reference(1) 24.348.98 Points you to the exact section of Alcatel-Lucent Technical Practices

where you can find more information on the topic being discussed.

Warning

Alerts you to instances where non-compliance could result in equipment damage orpersonal injury.


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About this Student Guide [cont.]




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11

Self-assessment of Objectives

At the end of each section you will be asked to fill this questionnaire

Please, return this sheet to the trainer at the end of the training


Instructional objectivesYes (orglobally

yes)

No (orglobally

no)Comments

1 To be able to XXX

2

Contract number :

Course title :

Client (Company, Center) :

Language : Dates from : to :Number of trainees : Location :

Surname, First name :

Did you meet the following objectives ?

Tick the corresponding box

Please, return this sheet to the trainer at the end of the training


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12

Self-assessment of Objectives [cont.]


Instructional objectivesYes (orGlobally

yes)

No (orglobally

no)

Comments

Thank you for your answers to this questionnaire

Other comments


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Section 1 Module 1 Page 1


3JK12191AAAAWBZZA Issue 1

Do not delete this graphic elements in here:


Module 1Introduction


Section 1B11 GSM QoS Monitoring

GSM B11

BSS B11 GSM Quality of Service & Traffic Load MonitoringTMO18096 D0 SG DEN I1.0 Issue 1


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GSM B11 BSS B11 GSM Quality of Service & Traffic Load MonitoringB11 GSM QoS Monitoring Introduction

1 1 2

Blank Page


First edition, B11 MR1Xavier Pourtauborde29-June-201001

RemarksAuthorDateEdition

Document History


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1 1 3

Module Objectives

Upon completion of this module, you should be able to:

Explain what is QoS and Traffic Load monitoring of the BSS

Explain what are the information sources available for that purpose


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1 1 4

Module Objectives [cont.]



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1 1 5

Table of Contents

Switch to notes view! Page

1 Monitoring the QoS of the BSS 7Definition 8Scope of Work 9

2 Monitoring the Traffic Load of the BSS 10Definition 11

3 Information Sources Available 12Observation Tools 13Interface Trace 16Example of Abis & A Traces 17Example of Traces Post-Processing 18Example of Drive-Test 20Performance Measurement Counters 21Exercise 22Alcatel-Lucent BSS Counters 23BSS Counter Example 24Exercise 26

4 Introduction to K1205 PC Emulation 27

Usage 28Measurement Scenarios Screen 29Filter Configuration 30Monitor Screen 31Extract a Call 32Call Extraction 33Exercise 34

5 Indicators Definition 35BSS Indicators Definition (Alcatel-Lucent) 36Typical KPI for BSS 37Typical KPI for Drive-tests 38Typical Thresholds 39Typical KPI Report 40

6 Methodological Precautions 41

Objective 42Network Element Aggregation 43Global Indicator Validity 44Time Period Aggregation 45Exercise 46Self-assessment on the Objectives 47End of Module 48


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1 1 6

Table of Contents [cont.]




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1 1 7

1 Monitoring the QoS of the BSS


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1 1 8


Definition

"Monitor" "network" "quality"

monitor = measure or ensure?

network = BSS? BSS+NSS? BSS+NSS+PSTN

quality = service (end-user) and/or system (technical)

But also detect, localize, diagnose outages

detect (decide according to thresholds)

localize (which cell, BSC, etc.)

diagnose: radio, BSS, TC problems


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All RightsReserved Alcatel-Lucent 2010


1 1 9


Scope of Work

Use all available tools at disposal to ensure:

Subscribers get good QoS

BSS equipments & interfaces are all runningefficiently (no alarms, no critical situation)

BSS Optimizers receive good inputs to enhancethe network

Management can characterize the network anddeploy operational teams accordingly


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1 1 10

2 Monitoring the Traffic Load of the BSS


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1 1 11

2 Monitoring the Traffic Load of the BSS

Definition

Measure the "quantity" of traffic handled by:

each equipment, each board

each interface

Analyze traffic characteristics

call, handover, location update, etc.

As input for dimensioning/architecture team

MSC/VLR GGSN

BTSBSC

BTS

BTS

BSC

Circuit Core

Network

IP

Network

GPRSbackbone

SGSNMFS


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1 1 12

3 Information Sources Available


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1 1 13


Observation Tools

System Performances: OMC-R PM (Performance Measurements) Counters

MSC/VLRGGSN

BTSBSC

BTS

BTS

BSC

Circuit Core

Network

IP

Network

GPRSbackbone

SGSNMFS

OMC-R NPO

GSM PM Files are located in the OMC-R: /alcatel/share/var/AFTR/APME/BSC

cf. PM file snapshot in the comments

9153-RA OMC-R: Operation and Maintenance Center Radio.

9159 NPO: Network Performance Optimizer, replace NPA + RNO since B10 onwards.

Extract from a PM File in OBSYNT format, from 17:00 to 17:30.


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1 1 14


Observation Tools [cont.]

NSS Performance: Core Network Counters

MSC/VLRGGSN

BTS BSC

BTS

BTS

BSC

Circuit

Core

Network

IPNetwork

GPRSbackbone

SGSN

MFS

OMC-CS


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1 1 15


Observation Tools [cont.]

Interfaces Traces: Capture messages through each interface

MSC/VLRGGSN

BTS BSC

BTS

BTS

BSC

Circuit

Core

Network

IPNetwork

GPRSbackbone

SGSN

MFS

Drive-testsAbis trace

A trace

Post-Processing tool


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1 1 16


Interface Trace

Use trace MS to capture

signaling and signal

characteristics

Capture/decode signaling

between BSC and BTS with

"protocol analyzer"

(Wandel, Tektronix,

Gnnettest, etc.)

Capture/decode signalingbetween MSC and BSC-TC(A or Ater MUX) with"protocol analyzer"(Wandel, Tektronix,Gnnettest, etc.)

Information source

Give precise location (x,y) ofproblems

Give downlink radio information Only way to localize a lack ofcoverage

Only way to monitor competitor

Complete information (messagecontents, time-stamp)

Possible detection ofUser/MS/BSS/TC/NSS problems

Complete radio informationthanks to measurement messages

Downlink and uplink

GSM standard, can be used forarbitrage between manufacturers

Complete information (messagecontents, time-stamp)

Possible detection ofUser/MS/BSS/TC/NSS problems

Advantages

High cost of equipment

Very time-consuming

Difficulty to perform a lot of calls

-> number of samples insufficient

-> only a few streets

No uplink


Time consuming, "post mortem"(installation of tool, file analysis)

Important expertise needed foranalysis

Very low coverage (A few RSLs, afew cell(s))

Very large amount of data (>> 10Mbytes/hour/BTS)


Time consuming, "post mortem"(installation of tool, file analysis)

Expertise needed for analysis

Low coverage (K1103/MA10: 8

COCs, K1205/MPA: 32 COCsmaximum!)

Large amount of data (>> 10 Mbytes/hour/BSC)

Drawbacks

Air interface

Abis Interface

A Interface

Interface

A interface :

The main advantage of the A interface is to allow the detection of Call Setup failures either due to the User or to the NSS (or PSTN).

Some typical user failure causes are: Some typical NSS failure causes are:

IMSI Unknown in VLR Temporary Failure

IMSI Unknown in HLR Resource UnavailableIMEI Not Accepted Switching Equipment Congestion

PLMN Not Allowed Normal Unspecified

Service Option Not Supported Recovery on Timer Expiry

Requested Service Not Supported Call Reject

Unassigned Number Interworking

Operator Determined Barring Protocol Error

User Alerting Network Failure

Facility Not Subscribed Congestion

No Route to Destination

Normal Call Clearing

User Busy

Invalid Number Format

Call Reject

Interworking

Normal Unspecified

CAUTION: In order to assess the QoS of a BSS or some cells of a BSS, all N7 links between this BSC and the MSC must be traced. Indeed, as theN7 signaling load is spread over all N7 links, signaling messages relating to one call can be conveyed on any of the active N7 links.

K1103 protocol analyzer can trace up to 8 COCs at the same time but on maximum 4 PCM physical links.

K1205 protocol analyzer can trace up to 32 COCs at the same time but on maximum 16 PCM physical links.

Abis interface : The main advantage of the Abis trace is to allow a detailed and precise assessment of the radio quality of a cell at TRX level.Both DL and UL paths can be observed and compared.

Air Interface : The main advantage of the Air trace is to assiciate a radio quality measurements to a given geographical area of the network.

From B7 release, the RMS feature implemented in the BSS provides a good level of information allowing to reduce the number of Abis traces

and drive test to be done for radio network optimization.


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1 1 17


Example of Abis & A Traces

K12 / K15 Protocol Analyzer


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1 1 18


Example of Traces Post-Processing

Detailed

visibility

on calls

& data

sessions

Enter subscribers ID - Select time frame

Failing

Calls

highlighted

Visibility /

Services

< 3 seconds

to display

individual

activity

Link to multi-interface

& protocol decoding for deep

investigation

Customer complaint analysis


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Example of Traces Post-Processing [cont.]

View at BSC level

Detailed call analysis shows that a group of su bscri bers

owning the same handset keep trying a LU every 2s

Abnormal level

of Location updates:

2 of biggest cities

particularly impacted

Vend

or3

Hand

set1

Vend

or1

Hand

set3

Vend

or5

Hand

set2

Vend

or2

Hand

set2

Vend

or4

Hand

set1

Vend

or5

Hand

set1

Vend

or 2

Hand

set1

Vend

or4

Hand

set2

Vend

or1

Hand

set4

Vend

or1

Hand

set2

Vend

or 2

Hand

set4

Vend

or3

Hand

set2

Vend

or 4

Hand

set4

Vend

or4

Hand

set3

Vend

or2

Hand

set3

Vend

or2

Hand

set5

Vend

or 3

Hand

set3

Vend

or3

Hand

set4

+

-

Location Update Failures per IMSI

Best / Worst performing handsets

Quality of handsets depending on various indicators (drops, call setup failures, etc.)


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1 1 20


Example of Drive-Test


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1 1 21


Performance Measurement Counters

Count "events" seen by sub-system, value reported periodically

+ Low cost: collected directly at OMC

+ Compact data: possibility to store counters for a complete network

- Raw information, having to be consolidated to be understandable

- Manufacturer's dependent: questionable/difficult to compare

- Weak to analyze other sub-systems

The main advantage of the BSS counters is to provide easily QoS data for permanent QoS monitoring.


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1 1 22


Exercise

Draw the BSS PM counters flow on the chart

In which sub-system are the BSS QoS indicators computed and stored?

BSC

BSC

BSC

OMC-R

OMC-R

OMC-R

NPO


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1 1 23


Alcatel-Lucent BSS Counters

Performance Management implementation

Easy and cost-effective way to monitor network and carried traffic

Principle: For a given duration (granularity period) typically 1 hour or hour

To count pre-defined events occurring on the Abis or A interface, or internalevents.

Counters stored with breakdown per network component (i.e. cell)

About 1100 counters are available (only for GSM).

Action: Open the GSM PM Counters database (MS-ACCESS format)

Alcatel-Lucent has chosen to implement PM counters in the BSC and to increment them mostly on Abis interface

signaling messages.

Other suppliers may have chosen to increment them on A interface signaling messages or to implement them in

the BTS.

Therefore caution should be taken when interpreting QoS indicators value since some discrepancies may be

observed due to these possible choices.

In order to provide the operators with an easy and cost-effective way to monitor their network and carried

traffic, BSS manufacturers have implemented specific software features, called performance management.

The principle is to count for a given duration called granularity period (typically 1 hour) pre-defined events

occurring on the Abis or A interface, or internally. These counters are stored for each duration, with breakdown

per network component (i.e. cell).


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BSS Counter Example

Counter Reference Counter Name

Smallest elementfor which thecounter is provided

All counters are described in PM Counters document.


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BSS Counter Example [cont.]

O 20 40 60 80 t

5 ts

10 ts

15 tsAt the end of the hour:180 samples every 20s

Hourly value = SUM ofsample /180

ts available

All counters are described in PM Counters document.


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1 1 26


Exercise

Observation Means: find the best source of information.

9 In a building, one is thinking that an elevator isinducing EM trouble, how to confirm?

8 discriminate problems between BSS/NSS. BSSand NSS from different providers.

7 compare networks quality

6 history of network quality for several weeks

5 localize abnormal cell in a network

4 localize precise location of a radio pb

3 get average network quality

Counters

Best source

Type 31 : RMS

Why

10 Identify potential interfering cells of 1 cell

2 monitor user failures

1 overall radio quality of 1 cell

Observation to be done

EM: Electro-Magnetic


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4 Introduction to K1205 PC Emulation


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Usage

The trace done with K1205 can be read:

Directly on K1205 itself

On any PC Windows NT with dedicated emulation software

Practical exercises will be done during the course using this software

The following slides and exercises are here to teach you the basic skillneeded to operate the tool for A Interface decoding


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Measurement Scenarios Screen

To select binarytrace file

To select binarytrace file

To enter inmonitoring mode to

analyze theA trace

To enter inmonitoring mode to

analyze theA trace

To filter the mainGSM protocols and

messages

To filter the mainGSM protocols and

messages

1. Start the K1205 Prot ocol Test erapplication.

2. In the Recordi ng Fil ebox: click on the Openbutton and select the "PAIB29.rec" file.

3. Select all displayed N7 logical links (corresponding to 4 PCMs in this case).

4. Click on the Browsebutton and select gsm2_A.stk in the gsm2 sub-directory (corresponding to the GSM Phase 2A interface protocol stack).

5. Click on OK.

6. Click on the Moni torbox to display the content of the recorded trace.


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Filter Configuration

Configure your filter to remove some messagesand protocols => Bypass Protocol Filterand select:

SCCP Except UDT

Keep all DTAP

BSSM Except PAGIN

Select also allLogical Links

ANNEX 4

The ANNEX 4 introduces some basics on the GSM protocol layers that will be traced for the A interface analysis.

UDT: Unit Data (for Signaling Control Point) Remove Paging information


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Monitor Screen

Short View1 line / message

Short View1 line / message

Frame ViewFull decoding of

selected message

Frame ViewFull decoding of

selected message

Packet viewMessage content

in hexadecimal

Packet viewMessage content

in hexadecimal

To extract 1 call

To extract 1 call


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1 1 32


Extract a Call

How to find a specific message?

Ed i t - Find(or ctrl + F3)

Select All Logical Links.

Choose the protocol.

Select the message studied.

Use F3 to find another same message.

How to extract a call from these traces?

Click on the Zoombutton.

Select CC message (Connection Confirm).

And UnZoom + Zoom to get:

SLR: Source Location Reference

LR: Destination Location Reference

At call setup, the first signaling message on the A interface is sent by the BSC to the MSC in order to set up a

logical link (called SCCP connection) between the BSS and the NSS.

Both BSS and NSS entities choose a unique reference which has to be used by the other party to identify the SCCP

connection on which the messages are conveyed. Both BSS reference (xxx) and NSS reference (yyy) areexchanged during the SCCP Connection Request and Connection Confirm phases. After that only the reference of

the other party is used.


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Call Extraction

Then

Click on the Fi l te rbutton and filter out all protocol layers and messages except:

all DTAP messages,

all BSSMAP messages except "Paging,

SCCP CR (Connection Request) and CC (Connection Confirm) messages.


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1 1 34


Exercise

Use the tool to extract a few calls from file PAIB29.REC

1) Zoom on a CC message:

Find the definition of all messages in the Frame View.

2) Zoom on a CR message with LUREQ.How to extract the complete call?

3) Use Find to extract a call with an ALERTING message.Can you see the CC message? If not, Why?


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5 Indicators Definition


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BSS Indicators Definition (Alcatel-Lucent)

Formula of counters

Call_drop_BSS = (Drops BSS Int. Fail. + Drops BSS Remote TC)

= (MC14c + MC739)

RTCH_Erlang_Total = (Occupancy RTCH) / 3600= (MC380a + MC380b) / 3600

Difference: Key Performance Indicator (KPI) or Detailed Indicator

KPI: For high-level monitoring, to measure progress towards organizationalgoals. KPI's are a subset of indicators, selected by radio engineers &managers.

"If all KPIs are fine, then everything is fine"

Detailed: Any other indicator, within the 4000 ALU Indicators! Fortroubleshooting and analysis of problems, known only by expert radioengineers.


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Call drop %

Rate of calls dropped after successful assignment

E2E Call Set-Up Success %

Rate of call setups successfully Outgoing Handover Success %

Rate of successful outgoing external and internal intercell SDCCH andTCH handovers

TCH congestion %

Rate of RTCH not allocated during normal assignment due to congestionon Air interface.

SDCCH unsuccess %

Rate of SDCCH not allocated during radio link establishment due tocongestion, radio problems or other problems.


Typical KPI for BSS

B11


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Typical KPI for Drive-tests

Call Establishment Success Rate

Rate of DL RxQual samples < 3

Rate of DL RxLev samples > -80dBm (beware of power control)

Voice Quality (MOS)


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Typical Thresholds

Not taking into account coverage or frequency planning

96.0%% Out HO Efficiency

1.0%% SDCCH Assign Cong

0.5%% SDCCH Drop

1.5%% RTCH Assign Fail

2.0%% RTCH Assign Cong

97.0%% Call Setup Success (ALU formula)

1.20%% RTCH drop1.50%% Call Drop

The Call Drop rate at network level has to compared to:

Contractual threshold: can be requested by the operator management to the operational radio team, can be

requested by the operator to the provider on swap or network installation

Quality threshold: fixed internally by radio team management.

Quality thresholds are usually tighter than contractual ones.


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1 1 40


Typical KPI Report

Observe this report from NPO. Is this cell below typical CSSR threshold?

Call success - CELL2G: cell00301_03017 (301/3017) ( 999/F77/301/3017 ) - 01/07/2009 To 07/07/2009

(Working Zone: Training - Medium)

0

100

200

300

400

500

600

700

800

900

01/07/2009 02/07/2009 03/07/2009 04/07/2009 05/07/2009 06/07/2009 07/07/2009

nb

97.5%

98.%

98.5%

99.%

99.5%

100.%

%

Assign Unsucc

Call drop

SDCCH drop

% End to End Call setup

% Call success

% Call setup

Call setup is above 97%


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6 Methodological Precautions


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1 1 42


Objective

Avoid typical errors regarding indicators interpretation

Rule: Good indicator value all componants are good

Ex: a BSC with CDR = 1% not all cells in the BSC are good !

a Cell with CSSR = 99% for one day not all hours are good !


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Network Element Aggregation

The average value of an indicator for a Network: Is not the average of cell results (or any sub-part of it)

BUT is the average weighted by the traffic

number o f ca l ls number o f cal l d r op ca ll d r op r a t e

cell 1 390 8 2,10%

cell 2 546 29 5,25%

cell 3 637 20 3,10%

cell 4 1029 12 1,14%

cell 5 536 3 0,50%

cell 6 2 1 50,00%

cell 7 3 1 33,00%

cell 8 210 4 2,11%

cell 9 432 5 1,20%

cell 10 321 4 1,11%

average of cell results 9,95%

total nb of drop/total number of calls 2,10%


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Global Indicator Validity

To be reliable, an indicator must be based on a sufficient number ofevents. Estimation theory gives a fresh look on our KPI:

If a sample (number of calls) is too small, then the indicator doesn't representa statistical reality but just a random occurrence of events.

MinMaxNb Calls

1.7%2.3%10000

1.6%2.4%5000

1.5%2.5%3000

1.4%2.6%2000

1.1%2.9%1000

0.9%3.1%600

0.6%3.4%400

0.1%3.9%200

0.0%4.7%100

0.0%10.7%10If displayed CDR = 2%, but

nb of calls =

if p is the probability of success for a complete population

if one is measuring the probability P based on a sample of size N

There is a probability of 95 % that p is between:P +/- 1.96*[(p*(1-p))/n]

Example: for p = 90 % and N = 100 => [ 84,12% ; 95,88% ]

On Alcatel-Lucent QoS monitoring tool (MPM application on OMC-R, NPA or RNO), NEs (BSS, Cell or TRX) are

highlighted with bad QoS indicator value if enough corresponding events have been observed (called Validity

threshold).

Examples:

Cells with bad Call Drop rate will be highlighted if CDR > CDR_threshold and if the Number of Calls is greater than

the CDR Validity threshold.

Cells with bad Outgoing handover success rate will be highlighted if OHOSUR > OHOSUR_threshold and if the

Number of Outgoing Handovers is greater than the OHO Validity threshold.


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1 1 45


Time Period Aggregation

TCH congestion rate at busy hour:

Weighted average of cell congestion at the busy hour of the network?

Weighted average of cell congestion rate for its specific busy hour?

time

erlangcongestion %

Cell A

Cell B

Cell C

Max traffic = Busy HourCongestion @ Busy Hour

Max congestion

Busy Hour at BSC levelnot the same as cells BH

BHa

BHb

BHc

BSCmax bh

Usually:

Cell Busy Hour = hour of the day where max TCH traffic (in erlang) is observed.

BSC Busy Hour = hour of the day where max TCH traffic (as the sum of the TCH traffic of all cells of the BSS) is

observed.


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1 1 46


Exercise

Is the conclusion given for each indicator right?

15346

4000

2000

215

4500

3267872

2315

2456435

Samples(calls)

BSS1 belonging to MSC Stadium

has a call setup success of 95%

LA = BSS1+BSS2 has a call drop

of 2.3%

Cell 15, 13 has certainly a

trouble

The call drop for BSS_1 is good

In France, call setup success=

97%

There is a good call setup

success rate for cell 15, 145

All the cells have a good call

drop

Conclusion

For BSS 1, call drop of 2%

For BSS 2, call drop of 3%

MSC has a call setup success of 95%

Call drop for cell 156,13 = 5%

Call drop rate for BSS = 1%

In Paris: 2500 cells with 95% of call setup success

In the rest of France: 5000 cells with 98%

Call setup success for cell 15, 145 = 99,5%

NOKCall drop = 0,9% in your country

OK / NOK ?Indicator


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1 1 47

Self-assessment on the Objectives

Please be reminded to fill in the formSelf-Assessment on the Objectivesfor this module

The form can be found in the first partof this course documentation


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1 1 48

End of ModuleIntroduction


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Module 2Indicators Overview



GSM B11



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GSM B11 BSS B11 GSM Quality of Service & Traffic Load MonitoringB11 GSM QoS Monitoring Indicators Overview

1 2 2

Blank Page


First edition B11 MR1Xavier Pourtauborde29-June-201001


Document History


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1 2 3

Module Objectives


Explain what is a detailed indicator and what are the different classifications

of the detailed indicators provided by the Alcatel-Lucent BSS


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1 2 4




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1 2 5

Table of Contents


1 Indicators Reference Name 7Description 8

2 Indicators Classification 9

BSS Counter Collection Mechanism 10BSS Performance Measurement Types 11Classification of GSM Indicators 12Formalism of Telecom Procedures 13SDCCH Traffic 14TCH Traffic 15QoS SDCCH 16QoS RTCH 17QoS Call Statistics 18Handover Causes 19Outgoing Handovers 20Incoming Handovers 21Intracell Handovers 22Handover Statistics per Couple of Cells 23

Self-assessment on the Objectives 24End of Module 25


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1 2 6





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1 2 7

1 Indicators Reference Name


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1 2 8

1 Indicators Reference Name

Description

Each QOS indicator has a unique REFERENCE NAME of 10 characters.

UnitFamily

Procedure Type Joker

Prefix Sub-type

mandatory

optionalTechnology

B11

Tehnology: G (GSM), U (UMTS), W (WiMaX)


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1 2 9

2 Indicators Classification


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1 2 10


BSS Counter Collection Mechanism

Cumulative

The counter is incremented at the occurrence of a specific event.

Abis or A message, or internal event.

At the end of a collection period, the result is the sum of the events.

Inspection

Every 20 or 10 seconds, a task quantifies an internal resource status (usuallya table).

At the end of a collection period, the result is the mean value.

Observation

Set of recorded information about a telecom procedure (handover, channelrelease, UL & DL measurements reporting).

Radio Measurement Statistics

Aggregation of all "Measurement Results" for a day and a TRX/Cell.


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1 2 11


BSS Performance Measurement Types

2G Traffic flow meas.180

Overview meas.110

B11IP transport35

B9Voice Group Call Services34

B9Electro-Magnetic Emission33

B8Change of frequency band meas.32

Radio Measurement Statistics31

SMS CB meas.30

Directed retry meas.29

SDCCH HO28

1 cell2G TCH incoming HO per adj. meas.27

40 cellsTCH outgoing HO per adj. meas.26

SCCP meas.25

SMS PP meas.19

A interface meas.18

15 cellsTCH observation15

15 cellsOutgoing external HO obs.14

15 cellsIncoming external HO obs.13

15 cellsInternal HO obs.12

1 cellTCH meas. obs.11

15 cellsSDCCH obs.10

N7 meas.9

X25 meas.8

LapD meas.7

40 cellsTCH HO meas.6

40 cellsResource usage on TCH meas.5

40 cellsResource usage on SDCCH meas.4

40 cellsResource usage on CCCH meas.3

40 cellsResource availability meas.2

40 cellsTraffic meas.1

Since LimitationsNameType

B11

A standard PM type can be activated for the whole network. It means that the related counters are reported for

all the Network Elements they are implemented on (TRX, CELL, N7 link, X25 link, LAPD link, Adjacency).

A detailed PM type can be activated only on a sub-set of the network. It means that the related counters are

reported only for a limited number of Network Elements:

40 cells per BSS for PM types 1, 2, 3, 4, 5, 6, 26, 29

15 cells per BSS for PM types 10, 12, 13, 14, 15

1 cell per BSS for PM types 11, 27

Counter numbering rules:

Cyz: cumulative or inspection counters in PM types 1, 2, 3, 4, 5, 6, 18, 19, 25, 26, 27, 28, 29, 30, 32, 180

Ly.z: cumulative counters in PM type 7 (L stands for LAPD link)

Xy.z: cumulative counters in PM type 8 (X stands for X25 link)

Ny.z: cumulative counters in PM type 9 (N stands for N7 link)

Syz: observation counters in PM type 10 (S stands for SDCCH)

Ryz:: observation counters in PM type 11 (R stands for Radio measurements) HOyz: observation counters in PM type 12, 13, 14 (HO stands for HandOver)

Tyz: observation counters in PM type 15 (T stands for TCH)

RMSyz: cumulative counters in PM type 31 (RMS stands for Radio Measurement Statistics)

MCyz or MNy.z: cumulative counters in PM type 110 (M stands for Major)


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1 2 12


Classification of GSM Indicators

Control Channels

Traffic load

Call statistics

Global QoS Handover Resource

availability

Multiband

Densification

techniques

GSM indicators

3G to 2G HOA Channelavailability

SCCP

TCH

RTCH

Couple of cell

SDCCH/TCH HO

Intracell HO

Multilayer /Multiband

Network

Concentric cells

Inter-PLMN HO

SDCCH availability

RTCH availability

SDCCH

Outgoing HO Directed retryDynamic SDCCHSDCCH

Incoming HO

HO causes


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1 2 13


Formalism of Telecom Procedures

Telecom procedure-ATTEMPT

Telecom procedure-SUCCESS

Telecom procedure-whose channel isALLOCATED in BSC

channel activationfailure

assignment/HOexecution failure

PREPARATIONphase

EXECUTIONphase

failure in channelestablished phase

the MS has seizedthe channel

- radio link failure- handover execution failure(with or without reversionto the old channel)- BSS problem- NSS problem

- radio link failure- BSS problem- NSS problem

Telecom procedure-REQUEST

- BSS problem- NSS problem

- congestion

no resource availablein BSC

resource availablein the BSC

channel activationsuccess

(start)

(end)

Success Rate = (Success) / (Request)Efficiency Rate = (Success) / (Allocated)Unsuccessful Rate = (Preparation & Execution Failures) / (Request)Failure Rate = (Failure) / (Request)


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1 2 14


SDCCH Traffic

Traffic Load and Traffic Model

SDCCH traffic

Estab

SDCCH Traffic

TrafficMT

TrafficMO

Loc. Update

IMSI Detach

Sup. Service

Call

LU Follow on

SMS

CallRe-Estab

Other

MS

Penetration Rate

TrafficDual Band

Resource

Occupancy

SDCCHErlang

SDCCH MeanHolding TimeGlobal

Traffic

GlobalRequests

Traffic

Model

HandoverNormalAssignment

NormalAssignment

Handover

The Traffic model section includes indicators for:

number of SDCCH connection requests and successes (Immediate Assignment, HO).

distribution of SDCCH connection success (MO and MT connections versus all MO+MT connections, type of MO

connections versus all MO connection types).

The MS penetration rate section includes the indicator for percentage of multiband MS SDCCH access (except LU)

versus all MS SDCCH accesses.

The Resource occupancy section includes indicators for:

SDCCH traffic in Erlang.

average duration in seconds of SDCCH channel usage.


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1 2 15


TCH Traffic

Traffic Load and Traffic Model

TCH traffic RTCH Traffic

Resource

Occupancy

TCHErlang

Full Rate

Erlang

Full RateAllocated

Full RateMean TCH

Time

Half Rate

Erlang

Half RateAllocated

Half RateMean TCH

Time

Blocking Peak

Ratio ofHR Traffic

TCHMultiband

Occupancy

Traffic Model

REQUESTS

Assign / HO / DR

SUCCESSAssign/ HO/ DR

HO PER CALL

REQUESTS

FR, DR, DR/EFR, AMR, DATA

Speech Version&

Channel Type

ALLOCATIONS

FR, HR, EFR, AMR, DATA

SUCCESSAMR / TFO

The Speech Version and Channel Type section includes indicators for:

distribution of TCH allocation requests (FR/DR/DR+EFR/AMR/DATA).

distribution of TCH allocation successes (FR/DR/DR+EFR/AMR/DATA).

rate of TCH AMR allocation successes. rate of TFO calls versus all speech calls.

The Traffic model section includes indicators for:

number of TCH connection requests and successes (Normal Assignment, HO, DR).

rate of TCH allocation successes for HO+DR versus all TCH allocations (NA+HO+DR).

number of HOs per call.

The Resource occupancy section includes indicators for:

RTCH traffic in Erlang (FR+HR, FR, HR, multiband).

average duration in seconds of RTCH channel usage (FR+HR, FR, HR).

number of TCH FR allocations and number of TCH HR allocations.

rate of TCH HR allocations versus all TCH allocations (FR+HR).

TCH peak of blocking (TCH congestion time).


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1 2 16


QoS SDCCH

GLOBAL Quality of Service

SDCCHSDCCH

Established

Phase

Drop Rate

Drop Radio Drop HO

Unsuccess

Congestion

Assignment Phase/

Handover

RadioFailure

BSS Failure

Access Reject

Dynamic Allocation

Drop BSS


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1 2 17


QoS RTCH

GLOBAL Quality of service

RTCH

DirectedRetry

RTCH

Unsuccess

Assignment Phase/

Handover

Global RadioCongestion Level

Congestion

Radio

Failure

BSS

Failure

EstablishedPhase

Drop rate

Drop Radio

Drop BSS

Drop HO

Preemption

PreemptionPhase

PCI =1 PVI =1

Requests

Allocationwith / withoutPreemption

Failure

Success

Success

QueuingPhase

Queue Length

AssignQueuing Fail

Assign

Queued& Reject

Queued

Success

Queue Full

HigherPriority

Timeout

AssignQueued

NormalAssign.


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1 2 18


QoS Call Statistics

GLOBAL Quality of service

Call statisticsCall Statistics

Call Success

Call SetupSuccess Rate

CallSuccess Rate

Cell QualityFactor Absolute

Cell Quality

Factor Relative

Call Drop

Call Drop Rate

Drop Radio Drop BSSDrop HO

Transcoder Failure

BSS Internal Failure

Call DropEnd User Rate

Preemption

End to EndCall Setup

Success Rate


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1 2 19


Handover Causes

Handover STATISTICS

Handover causes

Handover causes

HO causes

All

HO

cause

distribution

Outgoing HO Incoming HO

HO standard

cause

distribution

HO cause

category

distribution

HO causes per Adjacency

HO cause

category

distribution

Fast traffic HO taken into account type of counter for dual band HO


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1 2 20


Outgoing Handovers

Handover STATISTICS

Outgoing handovers

Failure With Reversion

Call Drop Rate

Efficiency

Preparation Success Rate

Intra-BSC


Call Drop Rate

Efficiency


External

Call Drop Rate

Efficiency

Success Rate

Intra-BSC & External

Outgoing HO

LAPD counter to analyze the cause of delay in HO procedures


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1 2 21


Incoming Handovers

Handover STATISTICS

Incoming handovers

Failure BSS

Failure Radio

Congestion

Efficiency

Intra-BSC

Failure BSS

Failure Radio

Failure No CIC

Congestion

Efficiency

External

Efficiency

Intra-BSC & External

Incoming HO

Incoming external HO 3G - > 2G

Incoming external HO 2G - > 2G only


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1 2 22


Intracell Handovers

Handover STATISTICS

Intracell handovers

New B9 counters: HO Cause 30 NB_TCH_HO_REQ_30_ReturnCSZone

=MC480 (Type 110)

NB_TCH_HO_ATPT_30_ReturnCSZone=MC481 (Type 110)

CDR Radio CDR BSS


Failure BSS

Call Drop Rate

Congestion

Efficiency

Intracell HO


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1 2 23


Handover Statistics per Couple of Cells

Handover STATISTICS

Handover statistics per couple of cell

HO Success Distribution

Success Rate

Efficiency


HO statistics

per Couple of Cell


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1 2 24

Self-assessment on the Objectives

Please be reminded to fill in the formSelf-Assessment on the Objectivesfor this module

The form can be found in the first partof this course documentation


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1 2 25

End of ModuleIndicators Overview


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Module 3Call Establishment



GSM B11



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GSM B11 BSS B11 GSM Quality of Service & Traffic Load MonitoringB11 GSM QoS Monitoring Call Establishment

1 3 2

Blank Page


First edition B11 MR1Xavier Pourtauborde28-june-1001


Document History


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1 3 3

Module Objectives


Explain what is a Global indicator and what are the main BSS indicators

regarding GSM services provided by the Alcatel-Lucent BSS


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1 3 4




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1 3 5

Table of Contents


1 Call Setup Principles 7Objective 8Call Setup Procedure 1/2 9

Call Setup Procedure 2/2 10Call Setup phasing 11Paging 12Successful Paging Procedure 13Paging Discarded due to PCH Congestion 14Paging Coordination 15Paging Request, Air Interface 17

2 Typical Call Setup Failures 18RLE Originated Call Success 19RLE Terminated Call Success 20RLE - Channel Request Message 21RLE Call Distribution 22RLE - SDCCH Congestion Failure 23RLE - SDCCH Congestion 24

RLE - SDCCH Congestion 25RLE - SDCCH Cong. Impacts 26RLE - SDCCH Cong. Causes & Solutions 27RLE Dynamic SDCCH 29RLE - SDCCH Radio Failure 30RLE - Real SDCCH Radio Failures 31RLE - Ghost RACH 32RLE - Ghost RACH Causes 33RLE Same BCCH-BSIC couple (Channel Req.) 35RLE Same freq-BSIC couple (HO Access) 36RLE - BSS Failure 38RLE - Summary 39RLE - Indicators 40Convention 41

SDCCH Phase Originated Call Success 42SDCCH Phase Terminated Call Success 43SDCCH Phase Location Update Success 44SDCCH Phase - Drops 45SDCCH Phase - Radio Drop 46SDCCH Phase - BSS Drop 47SDCCH Phase - HO drop 48SDCCH Phase - Counters 49SDCCH Phase - Indicators 50SDCCH Phase - Exercise 51TCH Assignment Success Case 52TCH Assignment Phase Split 53TCH Assignment MS Capabilities 54TCH Assignment - Congestion 55

TCH Assignment Exercise 56TCH Assignment - Radio Failure in TCH Uplink 57TCH Assignment - Radio Failure in TCH Downlink 58TCH Assignment - Radio Failure at T3107 expiry 59TCH Assignment - BSS Problem 60TCH Assignment - Counters 61TCH Assignment - Indicators 62TCH Assignment - Exercise 63

3 Key Performance Indicators 64Reminder 65


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1 3 6



SDCCH Congestion Rate 66SDCCH Failure Rate 68SDCCH Drop Rate 70

TCH Assign Unsuccess Rate 72TCH Assign Unsuccess Rate Preparation Phase 73TCH Assign Unsuccess Rate Execution Phase 74Cell Congestion Rate 75Call Setup Success Rate 76Call Success Rate 78End to End Call Setup Success Rate 79Alc_Mono_Call 81Differences between CSSR and E2ECSSR 82Self-assessment on the Objectives 83End of Module 84


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1 3 7

1 Call Setup Principles


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1 3 8


Objective

Description of the main call setup success and failures cases, with:

Main specific counters

Main protocol timers

Diagnose the main case of failures on A interface traces using the K1205emulation software


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AllRights Reserved Alcatel-Lucent 2010


1 3 9

Subscription Checking

(calling party rights, call barring)

Translation of the Called Number


Call Setup Procedure 1/2

MSC/VLR

Establish Indication "CM Service Request"

HLR/AuC/SCP/

Channel Request (RACH)

Immediate Assignment

(AGCH)

Security Checks

MM Authentication Procedure

CC Setup

CC Call Proceeding

Assignment Request(CIC)

Assignment Complete

Assignment Command

Assignment Complete

MM/RR Ciphering Procedure

MM/RR TMSI Reallocation Procedure

Call

Setup

Phase

MM Identity Request

Release of

SDCCH Radio

Channel

SDCCH

TCH

CCCH

BSSMS


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1 3 10


Call Setup Procedure 2/2

MSC/VLR HLR/AuC/SCP/

BSSMS

ISUP ACM

CC Alerting

ISUP IAM

Conversation phase

CC Connect

CC Connect Ack.

Called partyfree & ringing

ISUP ANC Called partyAnswered

MAP Send Routing Info.

MAP Send Routing Info. ResIf Called Nb

= MSISDN

CC Disconnect

CC Release

CC Release Complete

ISUP CLF

ISUP RLGRelease of Radio Resources

Call

Setup

Phase

Call

Rel.Phase

Conv.

Phase

V-MSC/VLR

TCH

Steps of a Basic SS7 Call:

1) The caller takes the phone "off-hook", dial the destination number. The subscriber signaling pass this

information to the local calling office.

2) The local originating office which use SS7, encapsulates the dialed number and the CPC (calling Party

Category) information in to the first signal IAM (Initial Address Message) to setup the call to the destinationoffice. In some cases IAM can be replaced with IAI (Initial Address Message with Additional Information) to pass

more information.

3) On the route to the destination each receiving office checks the DPC (Destination Point Code) with its own

Point Code to see if the message is destined to itself. If not it transfers the message to the next office in the

route. When the destination office finally receives the IAM or IAI, it checks the subscriber number to see if it's

free. If free then sends back the ACM (Address Complete Message).

4) At this point, the voice circuit is opened, ring back tone is put on the circuit back to the caller and ringing

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