SiemensInformationSystemPM: SBS Key Performance Indicators  (optional issue)A30808-X3247-M47-1-7618Date      : 06.10.2005R...
Information                                                                 PM: SBS Key Performance IndicatorsSystemConten...
Information                                                              PM: SBS Key Performance IndicatorsSystem      9.5...
Information                                                               PM: SBS Key Performance IndicatorsSystem      18...
Information                             PM: SBS Key Performance IndicatorsSystem1       Introduction1.1 PurposeThe purpose...
Information                            PM: SBS Key Performance IndicatorsSystem1.4 Definition of TermsLong nameThis is the...
Information                             PM: SBS Key Performance IndicatorsSystemElementary objectThis is the smallest meas...
Information                                  PM: SBS Key Performance IndicatorsSystem    -   SPBH is the value of the KPI ...
Information                              PM: SBS Key Performance IndicatorsSystem2       Immediate Assignment AnalysisThe ...
Information                                  PM: SBS Key Performance IndicatorsSystemThe following figure shows you the tr...
Information                             PM: SBS Key Performance IndicatorsSystem2.1 Number of Immediate Assignment Attempt...
Information                             PM: SBS Key Performance IndicatorsSystem2.3 Number of Immediate Assignments by BSC...
Information                             PM: SBS Key Performance IndicatorsSystem2.4 Number of AGCH LossesLong name:     (a...
Information                             PM: SBS Key Performance IndicatorsSystem2.6 Number of Immediate Assignments withou...
Information                               PM: SBS Key Performance IndicatorsSystem2.8 Immediate Assignment Loss RateLong n...
Information                               PM: SBS Key Performance IndicatorsSystem2.10 Immediate Assignment without MS Sei...
Information                             PM: SBS Key Performance IndicatorsSystem3       SSS Procedures AnalysisThe KPIs of...
Information                               PM: SBS Key Performance IndicatorsSystemThe following figure shows you the traff...
Information                             PM: SBS Key Performance IndicatorsSystem3.1 Number of successful Immediate Assignm...
Information                             PM: SBS Key Performance IndicatorsSystem3.2 Number of Dropped SDCCH Connections re...
Information                                 PM: SBS Key Performance IndicatorsSystem3.4 SDCCH Drop Rate related to Call Se...
Information                               PM: SBS Key Performance IndicatorsSystem3.6 SSS Procedures Success Rate related ...
Information                                    PM: SBS Key Performance IndicatorsSystem4         Assignment AnalysisThe KP...
Information                                 PM: SBS Key Performance Indicators   System   The following figure shows you t...
Information                             PM: SBS Key Performance IndicatorsSystem4.1 Number of Assignment AttemptsLong name...
Information                               PM: SBS Key Performance IndicatorsSystem4.2 Number of Assignment FailuresLong na...
Information                                      PM: SBS Key Performance IndicatorsSystem4.3 Number of successful Assignme...
Information                                  PM: SBS Key Performance IndicatorsSystem4.4 Assignment Failure RateLong name:...
Information                                PM: SBS Key Performance IndicatorsSystem4.5 Assignment Success RateLong name:  ...
Information                                 PM: SBS Key Performance IndicatorsSystem5         Call Setup AnalysisThe KPIs ...
Information                              PM: SBS Key Performance IndicatorsSystem5.1 Number of Call Setup AttemptsLong nam...
Information                               PM: SBS Key Performance IndicatorsSystem5.3 Call Setup Success RateLong name:   ...
Information                                PM: SBS Key Performance IndicatorsSystem               (e)   CSFailSDCCHDrop   ...
Information                               PM: SBS Key Performance IndicatorsSystem5.5        Call Setup Failure RateLong n...
Information                             PM: SBS Key Performance IndicatorsSystem6       TCH Drop related Performance Indic...
Information                              PM: SBS Key Performance IndicatorsSystem6.2 TCH Drop DistributionLong name:     (...
Information                               PM: SBS Key Performance IndicatorsSystemFormula:                                ...
Information                            PM: SBS Key Performance IndicatorsSystem              TCHDropDist.InterBSCHO.      ...
Information                               PM: SBS Key Performance IndicatorsSystem6.3 TCH Drop RateLong name:     (a) TCH ...
Information                                 PM: SBS Key Performance IndicatorsSystem6.4 Call Drop RateLong name:     (a) N...
Information                            PM: SBS Key Performance IndicatorsSystem                     NRCLRREQ[4,13]; this a...
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simemense KPI

  1. 1. SiemensInformationSystemPM: SBS Key Performance Indicators (optional issue)A30808-X3247-M47-1-7618Date : 06.10.2005Release : BR8.0
  2. 2. Information PM: SBS Key Performance IndicatorsSystemContents 1 INTRODUCTION ............................................................................................................................................. 5 1.1 Purpose.............................................................................................................................................. 5 1.2 Reference Documents ........................................................................................................................ 5 1.3 Issue History...................................................................................................................................... 5 1.4 Definition of Terms............................................................................................................................ 6 2 IMMEDIATE ASSIGNMENT ANALYSIS............................................................................................................ 9 2.1 Number of Immediate Assignment Attempts .................................................................................... 11 2.2 Number of Immediate Assignment Losses ....................................................................................... 11 2.3 Number of Immediate Assignments by BSC procedure ................................................................... 12 2.4 Number of AGCH Losses................................................................................................................. 13 2.5 Number of Immediate Assignment Commands sent to MS via AGCH............................................. 13 2.6 Number of Immediate Assignments without MS Seizure.................................................................. 14 2.7 Number of successful Immediate Assignments ................................................................................ 14 2.8 Immediate Assignment Loss Rate .................................................................................................... 15 2.9 AGCH Loss Rate.............................................................................................................................. 15 2.10 Immediate Assignment without MS Seizure Rate............................................................................. 16 2.11 Immediate Assignment Success Rate ............................................................................................... 16 3 SSS PROCEDURES ANALYSIS ..................................................................................................................... 17 3.1 Number of successful Immediate Assignments related to Call Setups............................................. 19 3.2 Number of Dropped SDCCH Connections related to Call Setups................................................... 20 3.3 Number of SSS Procedure Failures related to Call Setups ............................................................. 20 3.4 SDCCH Drop Rate related to Call Setups....................................................................................... 21 3.5 SSS Procedures Failure Rate related to Call Setups ....................................................................... 21 3.6 SSS Procedures Success Rate related to Call Setups....................................................................... 22 4 ASSIGNMENT ANALYSIS ............................................................................................................................. 23 4.1 Number of Assignment Attempts...................................................................................................... 25 4.2 Number of Assignment Failures ...................................................................................................... 26 4.3 Number of successful Assignments .................................................................................................. 27 4.4 Assignment Failure Rate ................................................................................................................. 28 4.5 Assignment Success Rate ................................................................................................................. 29 4.6 Assignment success rate when radio resources available ............................................................... 29 5 CALL SETUP ANALYSIS .............................................................................................................................. 30 5.1 Number of Call Setup Attempts........................................................................................................ 31 5.2 Number of Successful Call Setups ................................................................................................... 31 5.3 Call Setup Success Rate................................................................................................................... 32 5.4 Number of Call Setup Failures ........................................................................................................ 32 5.5 Call Setup Failure Rate ................................................................................................................... 34 6 TCH DROP RELATED PERFORMANCE INDICATORS ..................................................................................... 35 6.1 Number of Dropped TCH Connections ........................................................................................... 35 6.2 TCH Drop Distribution ................................................................................................................... 36 6.3 TCH Drop Rate................................................................................................................................ 39 6.4 Call Drop Rate ................................................................................................................................ 40 6.5 Mean Time between TCH Drop....................................................................................................... 42 6.6 TCH Drops per Erlanghour............................................................................................................. 42 7 SDCCH DROP RELATED PERFORMANCE INDICATORS ............................................................................... 43 7.1 Number of dropped SDCCH Connections ....................................................................................... 43 7.2 SDCCH Drop Rate .......................................................................................................................... 43 7.3 Mean Time between SDCCH Drop.................................................................................................. 44 7.4 SDCCH Drops per Erlanghour ....................................................................................................... 44 8 TCH LOAD RELATED PERFORMANCE INDICATORS .................................................................................... 45 8.1 TCH Load for Circuit Switched Traffic ........................................................................................... 45 8.2 Combined time slot utilisation for CS and PO Traffic..................................................................... 54 9 SDCCH LOAD RELATED PERFORMANCE INDICATORS ............................................................................... 56 9.1 SDCCH Traffic Offered ................................................................................................................... 56 9.2 SDCCH Traffic Carried................................................................................................................... 57 9.3 SDCCH Traffic Lost ........................................................................................................................ 57 9.4 SDCCH Blocking Rate..................................................................................................................... 572 A30808-X3247-B912-1-7618
  3. 3. Information PM: SBS Key Performance IndicatorsSystem 9.5 SDCCH Loss Rate ........................................................................................................................... 58 9.6 SDCCH Mean Holding Time ........................................................................................................... 58 9.7 SDCCH Traffic Utilisation .............................................................................................................. 59 10 CCCH LOAD RELATED PERFORMANCE INDICATORS ............................................................................ 60 10.1 PCH load of downlink CCCH channels .......................................................................................... 62 10.2 AGCH load of downlink CCCH channels........................................................................................ 62 10.3 CCCH load downlink....................................................................................................................... 63 10.4 CCCH load uplink ........................................................................................................................... 63 10.5 PCH Loss Rate ................................................................................................................................ 64 10.6 AGCH Loss Rate.............................................................................................................................. 64 10.7 Invalid RACH Rate .......................................................................................................................... 65 11 PCCH LOAD RELATED PERFORMANCE INDICATORS ............................................................................ 66 11.1 PPCH load of downlink PCCCH channels...................................................................................... 68 11.2 PAGCH load of downlink PCCCH channels................................................................................... 68 11.3 PCCCH load downlink .................................................................................................................... 69 11.4 PCCCH load uplink......................................................................................................................... 69 11.5 PPCH Loss Rate .............................................................................................................................. 70 11.6 PAGCH Loss Rate ........................................................................................................................... 70 11.7 Invalid PRACH Rate........................................................................................................................ 71 12 SERVICE RELATED PERFORMANCE INDICATORS ................................................................................... 72 12.1 Total number of Service Requests.................................................................................................... 72 12.2 Service Request Distribution Rate ................................................................................................... 72 12.3 Rate of Service Requests served in the highest layer ....................................................................... 73 13 FEATURE RELATED PERFORMANCE INDICATORS .................................................................................. 74 13.1 Abis pool supervision....................................................................................................................... 74 14 HANDOVER RELATED PERFORMANCE INDICATORS ............................................................................... 76 14.1 Intra Cell Handovers ....................................................................................................................... 76 14.2 Inter Cell Intra BSC Handovers ...................................................................................................... 82 14.3 Inter Cell Inter BSC Handovers ...................................................................................................... 90 14.4 Inter System Handover between GSM and UMTS ........................................................................... 96 14.5 Other Handover Performance Indicators...................................................................................... 101 15 POWER AND QUALITY MEASUREMENTS ............................................................................................. 107 15.1 Interference Band Rate on idle TCH ............................................................................................. 107 15.2 Quality Link for N% FER .............................................................................................................. 107 15.3 Mean FER UpLink......................................................................................................................... 107 15.4 Power and Quality limits for N% Percentile on busy TCH ........................................................... 109 15.5 Distribution of power control levels on busy TCH ........................................................................ 110 15.6 Mean Level and Quality on busy TCH........................................................................................... 111 15.7 TA Distribution.............................................................................................................................. 112 15.8 RXQUAL Distribution ................................................................................................................... 112 15.9 RXLEV Distribution....................................................................................................................... 113 15.10 FER Distribution ........................................................................................................................... 113 15.11 Mean FER UpLink per RXQUAL .................................................................................................. 114 15.12 Mean RXLEV per RXQUAL Band ................................................................................................. 115 15.13 Mean RXLEV per TA Band............................................................................................................ 116 15.14 High RXLEV with Low RXQUAL Rate .......................................................................................... 117 15.15 TCH Traffic Type Distribution ...................................................................................................... 118 15.16 SDCCH Traffic Type Distribution ................................................................................................. 119 15.17 Adaptive Multirate Distribution .................................................................................................... 120 15.18 Adaptive Multirate True Frame Erasure Rate............................................................................... 121 16 AVAILABILITY RELATED PERFORMANCE INDICATORS .......... FEHLER! TEXTMARKE NICHT DEFINIERT. 16.1 Transceiver Availability ................................................................................................................ 122 16.2 TCH Distribution Rate................................................................................................................... 122 16.3 TCH Availability............................................................................................................................ 122 16.4 SDCCH Availability ...................................................................................................................... 124 17 GPRS RELATED PERFORMANCE INDICATORS .................................................................................... 125 17.1 User oriented KPIs ........................................................................................................................ 125 17.2 Network planning (dimensioning) ................................................................................................. 140 17.3 Network optimization..................................................................................................................... 152 17.4 Cell Reselection ............................................................................................................................. 156 18 MISCELLANEOUS PERFORMANCE INDICATORS ................................................................................... 1603 A30808-X3247-B912-1-7618
  4. 4. Information PM: SBS Key Performance IndicatorsSystem 18.1 BSC Processorload........................................................................................................................ 160 18.2 BTSE Processorload...................................................................................................................... 161 18.3 Paging Response / Location Update Ratio per Cell ...................................................................... 161 18.4 BSC <-> MSC/SMLC CCS7 Load................................................................................................. 162 19 BSS RELATED KPIS AT SIEMENS MSC............................................................................................... 163 20 APPENDIX ........................................................................................................................................... 164 20.1 List of BSS Performance Measurements........................................................................................ 1644 A30808-X3247-B912-1-7618
  5. 5. Information PM: SBS Key Performance IndicatorsSystem1 Introduction1.1 PurposeThe purpose of this document is the definitions of SBS Key Performance Indicators,which can be used in a uniform way. It is possible to compare Key PerformanceIndicators of different networks or to give statements about Quality, Performance,Capacity and more.This document will describe the most important Key Performance Indicators relevantfor GSM Mobile Networks. All listed formulas are valid for one elementary object andfor one elementary measurement period. Evaluation of multiple objects and formultiple measurement periods can be done as described in chapter 1.4..This KPI document does not provide planning rules for network dimensioning. It onlyprovides input data used for planning tools.1.2 Reference DocumentsFurther information about Performance Measurements can be found in the followingdocuments:• PM:SBS Counters, A30808-X3247-M40-#• PM:SBS Message Flow, A30808-X3247-M41-#• Training Documentation 1736 : BSS Performance Measurement• 3GPP TS52.402 Telecommunication management; Performance Management (PM); Performance measurements - GSM1.3 Issue HistoryIssue Date of issue Reason for of issueVersionBR8.0 AFI0.1 23.6.2005 First version for new release 8.0BR8.0 AFI0.2 11.8.2005 Second version for new release 8.0 - Modifications related to review comments - New KPIs added in chapter 10 and 13BR8.0 IUS 1.0 06.10.2005 SDCA KPI’s added, chapter 125 A30808-X3247-B912-1-7618
  6. 6. Information PM: SBS Key Performance IndicatorsSystem1.4 Definition of TermsLong nameThis is the full name of the described key performance indicator (KPI).Short nameThis is an abbreviation of the described key performance indicator.DescriptionThe description will give you a short explanation of the described key performanceindicator.FormulaThe formula will deliver the exact calculation of the described key performanceindicator. The formula is related to one elementary object and to one elementaryperiod. Multiple objects and multiple elementary periods can be added as describedunder ‘Evaluation of multiple objects for multiple elementary periods‘.Used parameterHere you can find either the SBS short identification of the used SBS performancemeasurement counters or the short name of the used key performance indicators.The related long names of SBS performance measurement counters you can find inthe appendix under ‘List of Performance Measurements‘. The SBS short identificationis a combination of measurement type and sub-counter. A measurement type canhave several sub-counters. Therefore the used sub-counters are listed in bracketswith following meaning:• [1] sub-counter 1 has to be taken.• [1,2,4] sub-counters 1, 2 and 4 have to be added.• [1..4] sub-counters 1, 2, 3 and 4 have to be added.• [1..4, 7..10] sub-counters 1, 2, 3, 4, 7, 8, 9 and 10 have to be added.• [all] all sub-counters have to be added.It is also possible that key performance indicators can have sub-indicators. In thiscase they are also listed in brackets.6 A30808-X3247-B912-1-7618
  7. 7. Information PM: SBS Key Performance IndicatorsSystemElementary objectThis is the smallest measurement object, which can be used for a KPI (e.g. BSC,Cell, TRX).Unit - The unit is related to a key performance indicator e.g. seconds, percent or none. - The unit “kbit” expresses 1000 bit. Same for “kbit/s”RemarkHere you will find additional important information for the key performance indicator.AggregationThe aggregation field will show you how to evaluate the KPI for multiple objects andfor multiple elementary periods. There are:• Daily aggregation: for every KPI we can calculate: - MAX/min value: the KPI value for the granularity period of one day is recorded. These values are processed to find the peak value, maximum (MAX) or the minimum value (min); - MAX/min Time provides the starting time of the granularity period of the peak value (MAX and min); - Mean/Sum daily value represents the mean/sum of the counter value, used in KPI’s formula, collected for the granularity period; it is the aggregation standard1 . - SPBH (Sample at Peak Busy Hour2) is the value of the KPI at reference BH and is calculated only in the busy hour; - SPBH Time provides the starting time of the hour of SPBH;• Several days aggregation: - MAX/MIN value: all the KPI values recorded for each granularity period for each day are processed to find the highest value (MAX) or the minimum value (min); - MAX/MIN Time provides the starting time and date of the granularity period of the MAX/min value; - TCMAX/TCMIN (Time Coherent MAX/min): for a number of days, counter values for each granularity period for each day are recorded. The values for the same granularity period for each day are averaged, determining the average day. The counter value in the granularity period in this average day give the highest value (TCMAX) or the lower value (TCmin) is taken; - TCMAX/TCMIN Time provides the starting time related to TCMAX/TCmin value; - Mean/Sum value: all the counter values, used in KPI’s formula, recorded for granularity periods for each day are processed to find the mean/sum value, it is the aggregation standard (refer to note 1); - ASPBH (Average Sample at Peak Busy Hour): each day the sample at peak busy hour is recorded and then these values are averaged;7 A30808-X3247-B912-1-7618
  8. 8. Information PM: SBS Key Performance IndicatorsSystem - SPBH is the value of the KPI at reference BH and is calculated only in the busy hour on the number of considered days; - SPBH Time and Date provides the starting time of the hour and the date of SPBH; - TCSPBH (Time Coherent Sample at Peak Busy Hour): on average day it can be defined the busy hour, and in this peak busy hour the sample is recorded; - TCSPBH Time (Time Coherent Sample at Peak Busy Hour Time): provides the starting time of the hour of TCSPBH; - Mean daily represents the average over a number of days of the mean daily value; - MAX_SPBH: each day the sample at peak busy is recorded and then the max of these values is considered.For example it can be required to calculate the Handover Success Rate with SPBHaggregation Function referring to BSC Processor Load measurement: - KPI(Aggregation Function[Reference variable]) - InterCellHOSuccRate(SPBH[BSCPRCLD[2]])1 Standard means that the evaluation can be done by adding or averaging thecounter values for single objects and single periods in the following way (standardaggregation):Counter (n, m) = ∑ Counter (i, t) i,t Counter (n, m) = Counter (i, t)i elementary objectt elementary periodn object (sum of elementary objects)m measurement period (sum of elementary periods)2 The busy hour is the hour in which the reference variable assumes the highestvalue within one day for a measured object for any performance indicator. When thegranularity period is smaller than 1 hour, this value is calculated with the slidingwindow algorithm.Not in any case it makes sense to evaluate the busy hour for each singleperformance indicator. It is also possible to make an assumption, that for Randomtraffic the busy hour for most different measurement objects will correlate. Thatmeans the busy hour is derived from a particular performance indicator and can beused for other performance indicators. E.g. the busy hour could be derived from theperformance indicator ‘BSC Processor load‘ and could than be used for all otherperformance indicators.8 A30808-X3247-B912-1-7618
  9. 9. Information PM: SBS Key Performance IndicatorsSystem2 Immediate Assignment AnalysisThe KPIs of this section are mainly used for deriving the Call Setup Success Rate(CSSR) and Call Setup Failure Rate (CSFR). The Key Performance Indicators (KPIs)are mostly related to the Mobile Station point of view, by meaning they will count theevents related to Mobile Stations. The message flow of the Immediate AssignmentProcedure is listed below. The numbers in brackets will indicate available SBSperformance measurements.MS BTS BSC CHANNEL REQUEST [1] CHANNEL REQUIRED [2] SDCCH CONGESTIONS CHANNEL ACTIV CHANNEL ACTIV ACK CHANNEL ACTIV NACK IMM. ASS CMD [3] [4] [5] IMM. ASS IMM. ASS REJECT [5] DELETE INDICATION SABM UA [6] ESTABLISH INDIC.Fig. 1 Message flow: Immediate Assignment ProcedureSBS Counter[1] CHANNEL REQUIRED ATIMASCA [1..14][2] SDCCH CONGESTIONS ATSDCMBS [1] (Congestions due to SDCCH HO are also counted)[3] IMM. ASS CMD (Abis Interface) SUIMASCA [1..6] (IMM. ASS. CMD. messages, which contain an IMM. ASS. REJ. message are not counted)[4] IMM. ASS CMD (Abis Interface) TACCBPRO [2] (including those IMM. ASS. CMD. messages that contain an IMM. ASS. REJ. message)[5] IMM. ASS CMD / IMM. ASS. REJ. (Um Interface) NACSUCPR [2] (difference between IMM. ASS.CMD and Del. Ind., including those IMM. ASS. CMD. messages that contain an IMM. ASS. REJ. message)[6] ESTABLISH INDICATION NSUCCHPC [1..22]9 A30808-X3247-B912-1-7618
  10. 10. Information PM: SBS Key Performance IndicatorsSystemThe following figure shows you the traffic flow. [1] Number of Immediate Assignment Attempts [3] Number of Imm Ass. by BSC procedure [2] Number of Immediate Assignment Losses [5] Imm Ass Command sent to MS via AGCH [4] Number of AGCH Losses [6] Number of Immediate Assignments [7] Number of successful without MS Seizure Immediate AssignmentsFig. 2 Traffic flow: Immediate Assignment ProcedureThis chapter contains the following ‘Number related’ KPIs:• Number of Immediate Assignment Attempts: [1]• Number of Immediate Assignment Losses : [2]= [1] – [3]• Number of Immediate Assignments by BSC procedure : [3] = [1] – [2])• Number of AGCH Losses: [4] = [9] * [3]• Number of Immediate Assignment Commands sent to MS via AGCH: [5] = [3] – [4] = (1- [9]) * [3]•• Number of Immediate Assignments without MS Seizure : [6] = [5] – [7] = [3] – [4] - [7]• Number of successful Immediate Assignments: [7]And the following ‘Rate related’ KPIs:• Immediate Assignment Loss Rate : [8] = [2] / [1]• AGCH Loss Rate: [9] = [4] / [3])• Immediate Assignment without MS Seizure Rate : [10] = [6] / [5]• Immediate Assignment Success Rate : [11] = [7] / ([1] – [6]) (Phantom RACHs are not counted, because they are not related to MS)The Immediate Assignment Failure Rate can be calculated as follows:Immediate Assignment Failure Rate = 1 - Immediate Assignment Success Rate orImmediate Assignment Failure Rate = Immediate Assignment Loss Rate * AGCH Loss Rate * Immediate Assignment without MS Seizure Rate10 A30808-X3247-B912-1-7618
  11. 11. Information PM: SBS Key Performance IndicatorsSystem2.1 Number of Immediate Assignment AttemptsLong name: (a) Number of Immediate Assignment AttemptsShort name: (a) ImmAssAttDescription: These indicators will give you the number of started Immediate Assignment procedures from MS point of view by counting the number of Channel Required messages.Formula: (a) ImmAssAtt = ATIMASCA[1 ..14]Used param.: ATIMASCA[1..14]Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted. In BR 7.0 a note was added in counter ATIMASCA. This fact does not affect the meaning or definition of the KPI.2.2 Number of Immediate Assignment LossesLong name: (a) Number of Immediate Assignment LossesShort name: (a) ImmAssLossDescription: These indicators will give you the number of SDCCH/TCH request, which were rejected, because no SDCCH/TCH was available or because of BTS channel activation failures.Formula: (a) ImmAssLoss = ImmAssAtt - ImmAssBSCp rocUsed param.: ImmAssAtt (2.1(a)) , ImmAssBSCproc (2.3(a))Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted. In BR 7.0 a note was added in counters ATIMASCA(1,9) and SUIMASCA8(1,10). This fact does not affect the meaning or definition of the KPI.11 A30808-X3247-B912-1-7618
  12. 12. Information PM: SBS Key Performance IndicatorsSystem2.3 Number of Immediate Assignments by BSC procedureLong name: (a) Number of Immediate Assignments by BSC internal procedureShort name: (a) ImmAssBSCprocDescription: These indicators will give you the number of successful Immediate Assignments of a channel by BSC internal procedure I. e. the indicator counts the cases when the Immediate Assignment Attempts (RACH) can be satisfied by an according idle channel.Formula: (a) ImmAssBSCp roc = SUIMASCA[1 ..6]Used param.: SUIMASCA[1..6]Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted.12 A30808-X3247-B912-1-7618
  13. 13. Information PM: SBS Key Performance IndicatorsSystem2.4 Number of AGCH LossesLong name: (a) Number of AGCH lossesShort name: (a) AGCHLossDescription: These indicators will give you the number AGCH losses by meaning of not transmitted Immediate Assignment Command messages over the AGCH on the Air Interface. Reason for AGCH failures are mainly AGCH overload. This formula is related to MS point of view, by meaning each MS related immediate assignment procedure should be stepped once. Therefore events, where no SDCCH/TCH was available or BTS channel activation failured are counted in the formula ‘Number of Immediate Assignment Losses’. => Only Delete Indication messages related to Immediate Assignment Command messages not containing an Immediate Assignment reject messages will rightly be counted.Formula: (a) AGCHLoss = AGCHLossRate * ImmAssBSCprocUsed param.: AGCHLossRate (2.9(a)) ,ImmAssBSCproc (2.3(a))Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted.2.5 Number of Immediate Assignment Commands sent to MS via AGCHLong name: (a) Number of Immediate Assignments Commands sent to MS via AGCHShort name: (a) ImmAssCmdAGCHDescription: The KPI provides the number of Immediate Assignments Commands sent to MS via AGCHFormula: (a) ImmAssCmdAGCH = (1 − AGCHLossRate) * ImmAssBSCprocUsed param.: ImmAssBSCproc (2.3(a)), AGCHLossRate (2.9(a))Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted.13 A30808-X3247-B912-1-7618
  14. 14. Information PM: SBS Key Performance IndicatorsSystem2.6 Number of Immediate Assignments without MS SeizureLong name: (a) Number of Immediate Assignments without MS SeizureShort name: (a) ImmAssNoSeizDescription: These indicators will give you the number of immediate assignments without seizure by MS. The main reasons for this behavior are Phantom RACHs, messages not foreseen for the observed cell. Other reasons are not received SABM messages due to air interface problems. This formula will count the difference between Immediate Assignment Command messages sent to the MS and the number of Establishment Indication messages. => not answered Immediate Assignment Commands.Formula: (a) ImmAssNoSe = ImmAssBSCp - AGCHLoss- ImmAssSucc iz rocUsed param.: ImmAssBSCproc (2.3(a)), AGCHLoss (2.4(a)), ImmAssSucc (2.7(a))Elem. Object: CellUnit: NoneRemarks: The formula will mainly detect Phantom RACHs. Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is started, but will not be successful, because no MS will reply with a SABM message. A BTS Timer will expire. In case of RACH repetitions (abnormal amount of time => Expiry of timer NSLOTST), it can happen that subsequent Immediate Assignment Commands will not receive a positive reply from the MS. Nevertheless from MS point of view the call setup was successful.2.7 Number of successful Immediate AssignmentsLong name: (a) Number of successful Immediate AssignmentsShort name: (a) ImmAssSuccDescription: These indicators will give you the number of successful Immediate Assignments from MS point of view. A Immediate Assignment procedure is successful if the BTS returns an establishment indication message on Abis.Formula: (a) ImmA ssSucc = NSUCCHPC[1 .. 6, 9 ..14, 17 .. 22]Used param.: NSUCCHPC[1 .. 6, 9 .. 14, 17 .. 22]Elem. Object: CellUnit: NoneRemarks: SMS related counters in NSUCCHPC have not to be considered in the KPI formula, because they are also included in other sub-counters of measurement NSUCCHPC.14 A30808-X3247-B912-1-7618
  15. 15. Information PM: SBS Key Performance IndicatorsSystem2.8 Immediate Assignment Loss RateLong name: (a) Immediate Assignment Loss RateShort name: (a) ImmAssLossRateDescription: These indicators will give you the SDCCH/TCH Loss Rate, which were rejected, because no SDCCH/TCH was available or because of BTS channel activation failures.Formula: Im mAssLoss (a) ImmAssLossRate = Im mAssAttUsed param.: ImmAssAtt (2.1(a)), ImmAssLoss (2.2(a))Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted (in ImmAssAtt).2.9 AGCH Loss RateLong name: (a) AGCH Loss RateShort name: (a) AGCHLossRateDescription: These indicators will give you the AGCH Loss Rate by meaning of not transmitted Immediate Assignment Command messages over the AGCH on the Air Interface. Reason for AGCH failures are mainly AGCH overload. This formula is related to MS point of view, by meaning each MS related immediate assignment procedure should be stepped once. Therefore events, where no SDCCH/TCH was available or BTS channel activation failured are counted in the formula ‘Number of Immediate Assignment Losses’. => Only Delete Indication messages related to Immediate Assignment Command messages not containing an Immediate Assignment reject messages will rightly be considered.Formula: TACCBPRO[2] - NACSUCPR[2] (a) AGCHLossRate = TACCBPRO[2]Used param.: TACCBPRO [2], NACSUCPR [2]Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. These unforeseen messages will also be counted.15 A30808-X3247-B912-1-7618
  16. 16. Information PM: SBS Key Performance IndicatorsSystem2.10 Immediate Assignment without MS Seizure RateLong name: (a) Immediate Assignment without MS Seizure RateShort name: (a) ImmAssNoSeizRateDescription: These indicators will give you the immediate assignment without MS seizure rate . The main reasons for this behaviour are Phantom RACHs, messages not foreseen for the observed cell. Other reasons are not received SABM messages due to air interface problems. This formula will count number of not answered Immediate Assignment Command messages related to the Immediate Assignment Command messages sent to the MS.Formula: ImmAssNoSeiz (a) ImmAssNoSeizRate = ImmAssCmdAGCHUsed param.: ImmAssNoSeiz (0(a)), ImmAssCmdAGCH (2.5(a))Elem. Object: CellUnit: NoneRemarks: The formula will mainly detect Phantom RACHs. Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is started, but will not be successful, because no MS will reply with a SABM message. A BTS Timer will expire.2.11 Immediate Assignment Success RateLong name: (a) Immediate Assignment Success RateShort name: (a) ImmAssSuccRateDescription: These indicators will give you the immediate assignment success rate from MS point of view. A Immediate Assignment procedure is successful if the BTS returns an establishment indication message.Formula: ImmAssSucc (a) ImmAssSuccRate = Im mAssAtt − Im mAssNoSeizUsed param.: ImmAssAtt (2.1(a)), ImmAssSucc (2.7(a)), ImmAssNoSeiz (0(a))Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are not included in this formula, because they are not related to MS of the observed cell. Um-Interface problems may lead to decoding errors of the Mobile’s L2 SABM- frame and therefore are not considered here.16 A30808-X3247-B912-1-7618
  17. 17. Information PM: SBS Key Performance IndicatorsSystem3 SSS Procedures AnalysisThe KPIs of this section are mainly used for the derivation of the Call Setup SuccessRate (CSSR) and Call Setup Failure Rate (CSFR). The Key Performance Indicators(KPIs) are mostly related to the Mobile Station point of view, by meaning they willcount the events related to Mobile Stations. There exists the following SSSProcedures which used during Call Setup related to the parameter setting in theMSC: Identity Check (IMEI), Authentication (IMSI), Ciphering, Call Control: SetupMS BTS BSC MSC SABM [1] Establishment Ind. CR(Compl Layer3Info) CC Authentification Request Authentification Response Identity Request Identity Response Ciphering Command Ciphering Command Ciphering Complete Ciphering Complete Setup Call Proceeding [2] Assignment Req. Assignment CommandFig. 3 Message flow: SSS Procedures during Call Setup (MOC)SBS Counter[1] ESTABLISH INDICATION NSUCCHPC[1..4,9..12,17..20] – NSUCCHPC[8] (related to Call Setups)[2] ASSIGNMENT ATTEMPTS TASSATT [2..3]Sub-counters are listed in BracketsThe different number of failures and failure rates can be evaluated with SiemensMSC counter per MSC. All events are cell independent. Therefore it is sufficient tocalculate them for the elementary object MSC.It is also very important to evaluate the number of SDCCH drops during call setup.SDCCH drops mainly occur in the time when SSS Procedures are running. Thereforethey can be evaluated together with the SSS Procedure formulas. With SBSperformance measurement counter it is possible to calculate the SSS ProcedureSuccess and Failure Rate related to Call Setups.17 A30808-X3247-B912-1-7618
  18. 18. Information PM: SBS Key Performance IndicatorsSystemThe following figure shows you the traffic flow. [1]Successful Immediate Assignments [2]SDCCH Drops [3] SSS Procedure failures [4] Assignment AttemptsFig. 4 Traffic flow: SSS Procedures during Call SetupSDCCH Drops can occur before SSS Procedure Failure and vice versa.This chapter contains the following ‘Number related’ KPIs:• Number of successful Immediate Assignments related to Call Setups: [1]• Number of Dropped SDCCH Connections related to Call Setups: [2]• Number of SSS Procedure Failures related to Call Setups: [3] = [1] - [4] - [2]And the following ‘Rate related’ KPIs:• SDCCH Drop Rate related to Call Setups = [2] / [1]• SSS Procedures Failure Rate related to Call Setups = [3] / [1]• SSS Procedures Failure Rate related to Call Setups = [4] / [1]Referenced KPI from chapter 4 Assignment Analysis• Number of Assignment Attempts: [4]18 A30808-X3247-B912-1-7618
  19. 19. Information PM: SBS Key Performance IndicatorsSystem3.1 Number of successful Immediate Assignments related to Call SetupsLong name: (a) Number of successful Immediate Assignments related to Call SetupsShort name: (a) ImmAssSuccCSDescription: These indicators will give you the number of successful Immediate Assignments related to Call Setups. A Immediate Assignment procedure related to a Call Setup is successful if the BTS returns an establishment indication message related to Mobile Originated Calls (MOC), Mobile Terminated Calls (MTC), Emergency Calls or Call Reestablishment.Formula: (a) ImmAssSuccCS = NSUCCHPC[1 ..4,9..12,17..20]- NSUCCHPC[8 ]Used param.: NSUCCHPC[1..4, 8 ..12,17..20]Elem. Object: CellUnit: NoneRemarks: • Partly elimination of systematic error in formula by subtracting the SMS-MT related counter values NSUCCHPC[8] (SDCCH assigned for SMS-MT). The new SMS counters are triggered on arrival of Establish Confirm (SAPI 3) • Remark (background information) The counters NSUCCHPC [16,24] must not be subtracted since they mainly are triggered where an SMS MT arrives when the MS has an ongoing TCH call. In that case no immediate TCH assignment in connection with the SMS MT takes place at all and thus an elimination of SMSes in formula 3.1 by subtracting "- NSUCCHPC [16,24]" is not necessary. • Remaining systematic error: The formula has a small systematic error when "Direct TCH Assignment” is enabled. For that scenario the counters NSUCCHPC [16,24] might also be triggered when an SMT MT arrives for an idle MS, which requests an immediate TCH assignment as paging response. The number of these concurrencies has in principle to be subtracted in formula 3.1. But NSUCCHPC [16,24] does no distinguish between arrival of SMS MT for an idle MS and for an MS with ongoing TCH call (the call processing trigger point used for NSUCCHPC [16,24] has no knowledge about the history of the existing TCH assignment).19 A30808-X3247-B912-1-7618
  20. 20. Information PM: SBS Key Performance IndicatorsSystem3.2 Number of Dropped SDCCH Connections related to Call SetupsLong name: (a) Number of Dropped SDCCH Connections related to Call SetupsShort name: (a) SDCCHDropCSDescription: This indicator will give you the number of dropped SDCCH connections related to Call Setups. SDCCH drops mainly occur during running SSS Procedures. This formula is related to the assumption that the number of dropped SDCCH connections is random distributed to all kind of assignment causes (MOC, MTC, Locupd, …). Therefore this formula contains a factor for the ratio of MOC and MTC to all kind of assignment causes to get the relation to Call Setups.Formula: ImmAssSuccCS (a) SDCCHDropCS = SDCCHDrop * ImmAssSuccUsed param.: SDCCHDrop(7.1(a)), ImmAssSucc (2.7(a)), ImmAssSuccCS (3.1(a))Elem. Object: CellUnit: NoneRemarks:3.3 Number of SSS Procedure Failures related to Call SetupsLong name: (a) Number of SSS Procedure Failures related to Call SetupsShort name: (a) SSSProcFailCSDescription: This indicator will give you the number of SSS Procedure failures related to Call Setups.Formula: (a) SSSProcFai lCS = ImmAssSuccCS - AssAtt - SDCCHDropC SUsed param.: ImmAssSuccCS (3.1(a), AssAtt (0(a)), SDCCHDropCS (3.2(a))Elem. Object: CellUnit: NoneRemarks: Please note that Authentication-, Identity-, Ciphering- and MSC failures are counted in this formula although they are not related to the BSS. User Release before assignment of a TCH is also included in this formula. Assignments of SDCCH are not considered.20 A30808-X3247-B912-1-7618
  21. 21. Information PM: SBS Key Performance IndicatorsSystem3.4 SDCCH Drop Rate related to Call SetupsLong name: (a) SDCCH Drop Rate related to Call SetupsShort name: (a) SDCCHDropRateCSDescription: This indicator will give you the SDCCH Drop Rate related to Call Setups. SDCCH drops mainly occur during running SSS Procedures. This formula is related to the assumption that the number of dropped SDCCH connections is random distributed to all kind of assignment causes (MOC, MTC, Locupd, …). Therefore this formula is equal to the SDCCH Drop Rate.Formula: SDCCHDropC S (a) SDCCHDropR ateCS = ≈ SDCCHDropR ate Im mAssSuccCSUsed param.: SDCCHDropCS (3.2(a)), ImmAssSuccCS (3.1(a)), SDCCHDropRate (7.2(a))Elem. Object: CellUnit: NoneRemarks: SDCCH Handovers are not considered here.3.5 SSS Procedures Failure Rate related to Call SetupsLong name: (a) SSS Procedures Failure Rate related to Call SetupsShort name: (a) SSSProcFailRateCSDescription: This indicator will give you the SSS Procedures Failure Rate by meaning the number of failures during SSS Procedures compared to the number of successful Immediate Assignment Procedures (Establishment Indication).Formula: SSS Pr ocFailCS (a) SSSProcFai lRateCS = Im mAssSuccCSUsed param.: SSSProcFailCS (3.3(a)), ImmAssSuccCS (3.1(a))Elem. Object: CellUnit: NoneRemarks: Please note that Authentication-, Identity-, Ciphering- and MSC failures are counted in this formula although they are not related to the BSS. User Release before assignment of a TCH is also included in this formula. Assignments of SDCCH are not considered.21 A30808-X3247-B912-1-7618
  22. 22. Information PM: SBS Key Performance IndicatorsSystem3.6 SSS Procedures Success Rate related to Call SetupsLong name: (a) SSS Procedures Success Rate related to Call Setups (b) Total SSS Procedures Success Rate related to Call SetupsShort name: (a) SSSProcSuccRateCS (b) SSSProcSuccRateCStotalDescription: The first Indicator will give you the SSS Procedures Success Rate related to Call Setups by meaning the rate for successful allocated Timeslots from MSC point of view (Assignment Request Message) minus the SDCCH Drop Rate related to Call Setups. This indicator is related to the Radio Network and is therefore recommended to find out Radio Network failures. The second indicator will give you the SSS Procedures Success Rate related to Call Setups by meaning the number of started Assignment Procedures (Assignment Requests) compared to the number of successful Immediate Assignment Procedures (Establishment Indications) related to Call Setups. Authentication-, Identity-, Ciphering- and MSC failures are among others counted within this indicator although they are not related to the BSS.Formula: (a) SSSProcSuccRateCS = 1 - SDCCHDropRateCS AssAtt (b) SSSProcSuccRateCStotal = or ImmAssSuccCS SSSProcSuccRateCStotal = 1 − SDCCHDropRateCS − SSS Pr ocFailRateCSUsed param.: ImmAssSuccCS (3.1(a)), AssAtt (0(a)), SDCCHDropRateCS (3.4(a)), SSSProcFailRateCS (3.5(a))Elem. Object: CellUnit: NoneRemarks: SSSProcSuccRateCStotal: Please note that Authentication-, Identity-, Ciphering- and MSC failures will lead to a worse Success Rate although they are not related to the BSS. User Release before assignment of a TCH is also included in the second formula. Assignments of SDCCH are not considered.22 A30808-X3247-B912-1-7618
  23. 23. Information PM: SBS Key Performance IndicatorsSystem4 Assignment AnalysisThe KPIs of this section are mainly used for the derivation of the Call Setup SuccessRate (CSSR) and Call Setup Failure Rate (CSFR). The Key Performance Indicators(KPIs) are mostly related to the Mobile Station point of view, by meaning they willcount the events related to Mobile Stations. The messageflow of the AssignmentProcedure is listed below (normal case). The numbers in brackets will indicateavailable SBS performance measurements.MS BTS BSC MSC [1] TASSATT (MTCHBUTI) ASSIGNMENT REQUEST PHYS CONTEXT REQ PHYS CONTEXT CONF CHAN ACTIV CHAN ACTIV ACK CHANNEL ACTIV NEG ACK [5] TASSFAIL ASSIGNMENT FAILURE ASSIGNMENT COMMAND ASSIGNMENT COMMAND SABM (TNTCHCL) ESTABLISH INDICATION UA ASSIGNMENT COMPLETE ASSIGNMENT COMPLETE [4] TASSSUCC ASSIGNMENT COMPLETEFig. 5 Message flow: Assignment Procedure (normal case)BSS Counter[1] ASSIGMENT ATTEMPS TASSATT [2..3][2] INCOMING REDIRECTED TASSSUCC [4..5][3] OUTGOING REDIRECTED CALLS SINTHINT [7] + SUINBHDO [10*n+7]; n = 0 ...31 (n= number of GSM ADJ-ids) + SUOISHDO[10 * m + 7] ; m = 0 ...63 (m= number of UMTS ADJ-ids)[4] ASSIGMENT COMPLETE (normal Assignm.) TASSSUCC [2..3][5] ASSIGMENT FAILURE TASSFAIL [6,7,8,10,11,12,13,15][6] Queuing Failure NMSGDISQ [1,2]23 A30808-X3247-B912-1-7618
  24. 24. Information PM: SBS Key Performance Indicators System The following figure shows you the traffic flow. Single Cell / Observed Cell [1] Assignment Attempts [5] Assignment [3]+[4] Assignment success [6] Queuing Failure[2] Successful inc. redirected Calls [4] Assignment Complete [3] Successful Outgoing redirected Calls Fig. 6 Traffic flow: Assignment Procedure The observed cell is the cell where the call establishment has been started (immediate assignment procedure). By aid of the feature Directed Retry a TCH may be assigned in a cell different from the observed cell. Also in that case the “success” is counted for the observed cell. The Assignment procedure is used to allocate a TCH. Because of new feature the Assignment Success Rate is not easy to evaluate. The Directed Retries have also to be considered. The concept how to evaluate Directed Retries for the Assignment Success Rate is comparable with the Handover Success Rate, where only outgoing Handover will be considered. Therefore all Directed Retries for an observed cell have to be counted, which where started in the observed cell and were successful in any target cell with neighbor cell measurements. Under this assumption the Assignment Success Rate can be evaluated as follows: Assignment Success Rate = (Assignment Complete [4] + Successful outgoing redirected Calls [3]) / Assignment Attempts [1] This chapter contains the following ‘Number related’ KPIs: • Number of Assignment Attempts: [1], see chapter 0. • Number of Assignment Failures: [5] ,see chapters 4.2(a), (b), (c) • Number of successful Assignments = [3]+[4], see chapter 4.3 • Number of Queuing Failures: [6], see chapter 4.2(d) This chapter contains the following ‘Rate related’ KPIs: • Assignment Failure Rate, see chapter 4.4 • Assignment Success Rate, see chapter 4.5 • "Assignment success rate when radio resources available, see chapter 4.6(a) 24 A30808-X3247-B912-1-7618
  25. 25. Information PM: SBS Key Performance IndicatorsSystem4.1 Number of Assignment AttemptsLong name: (a) Number of Assignment AttemptsShort name: (a) AssAttDescription: These indicators will give you the number of Assignment procedures started by the MSC.Formula: (a) AssAtt = TASSATT[2, 3]Used param.: TASSATT[2,3]Elem. Object: CellUnit: NoneRemarks: Only TCH assignments are considered. Assignments of SDCCHs are not considered. Only the assignment procedure triggered by the MSC is considered but not the Immediate Assignment procedure. Incoming handovers are also not considered.25 A30808-X3247-B912-1-7618
  26. 26. Information PM: SBS Key Performance IndicatorsSystem4.2 Number of Assignment FailuresLong name: (a) Number of TCH Losses (b) Number of Assignment Failures by Message (c) Number of Assignment Failures due to other Reason (d) Number of Queuing Failures (e) Total Number of Assignment FailuresShort name: (a) TCHLoss (b) AssFailbyMess (c) AssFailOther (d) QueFail (e) AssFailDescription: These indicators will give you the number of failed Assignments of a TCH.Formula: (a) TCHLoss = TASSFAIL[8,13] (b) AssFailbyM ess = TASSFAIL[6 ,7,10,11,1 2,15] (c) AssFailOther = AssAtt - AssSucc - TCHLoss - AssFailbyMess - QueFail (d) QueFail = NMSGDISQ[1,2] (e) AssFail = TASSFAIL[6..8, 10..13,15] + NRCLRREQ[22]Used param.: TASSFAIL [6,7,8,10,11,12,13,15], AssAtt (0(a)) , AssSucc (4.3(a)), NMSGDSIQ[1,2], NRCLRREQ[22]Elem. Object: CellUnit: NoneRemarks: • Directed Retries are not considered, because they ares not related to assignment failures • Assignments of SDCCH are not considered. • Sub-counters TASSFAIL[10] and TASSFAIL[15] (All other causes) used in formula (b) includes the A-interface and equipment related causes (see GSM 08.08). • Queuing failures are completely covered in formula (e). Measurement NMSDISQ[1,2] must not be added. But measurement NRCLRREQ[22] is included in case a queued subscriber is pre-empted before expiry of timer T11. • Formula (c) AssFailOther contains all other causes related to internal and transmission failures.26 A30808-X3247-B912-1-7618
  27. 27. Information PM: SBS Key Performance IndicatorsSystem4.3 Number of successful AssignmentsLong name: (a) Number of successful AssignmentsShort name: (a) AssSuccDescription: These indicators will give you the number of successful completed Assignment procedures. Successful completed Assignment procedures are incremented even with successful outgoing directed retry, because it represents an assignment of TCH for the originating cell.Formula: AssSucc = TASSSUCC[2,3] 31 63 + SINTHINT[7] + ∑ SUINBHDO[10 * n + 7] + ∑ SUOISHDO[10 * m + 7] (a) n =0 m =0 with n for the number of GSM neighbourcell relation (n=0..31) with m for the number of UMTS neighbourcell relation (m=0..63)Used param.: TASSSUCC[2,3], SINTHINT[7], SUINBHDO[10 * n + 7], SUOISHDO[10 * m + 7]Elem. Object: CellUnit: NoneRemarks: • Assignments of SDCCH are not considered. • Intersystem Directed Retry to UMTS are considered27 A30808-X3247-B912-1-7618
  28. 28. Information PM: SBS Key Performance IndicatorsSystem4.4 Assignment Failure RateLong name: (a) TCH Loss Rate (b) Assignment Failure Rate by Message (c) Assignment Failure Rate due to other Reason (d) Queuing Failure Rate (e) Assignment Failure RateShort name: (a) TCHLossRate (b) AssFailbyMessRate (c) AssFailOtherRate (d) QueFailRate (e) AssFailRateDescription: These indicators will give you the Assignment Failure Rates. The Assignment procedure is unsuccessful if the BSC returns a Assignment Failure message to the MSC or if the directed retry in the target cell was not successful.Formula: TCHLoss (a) TCHLossRate = AssAtt AssFailbyMess (b) AssFailbyMessRate = AssAtt AssFailOther (c) AssFailOtherRate = AssAtt QueFail (d) QueFailRate = AssAtt AssFail (e) AssFailRate = AssAttUsed param.: AssAtt(0(a)), TCHLoss (4.2(a)), AssFailbyMess (4.2(b)), AssFailOther (4.2(c)), QueFail (4.2(d)), AssFail (4.2(d)),Elem. Object: CellUnit: NoneRemarks: • Directed Retries are not considered, because they ares not related to assignment failures. • Assignments of SDCCH are not considered28 A30808-X3247-B912-1-7618
  29. 29. Information PM: SBS Key Performance IndicatorsSystem4.5 Assignment Success RateLong name: (a) Assignment Success RateShort name: (a) AssSuccRateDescription: These indicators will give you the Assignment Success Rate. The Assignment procedure is successful if the BSC returns an Assignment Complete message to the MSC or if the directed retry in the target cell was successful.Formula: AssSucc (a) AssSuccRate = or 1 − AssFailRate AssAttUsed param.: AssAtt(0(a)), AssSucc (4.3(a)), AssFailRate (4.4(e))Elem. Object: CellUnit: NoneRemarks: • Assignments of SDCCH are not considered. • Inter System Directed Retry (e.g. UMTS) are also considered4.6 Assignment success rate when radio resources availableLong name: (a) Assignment success probability when radio resource availableShort name: (a) SuccAssProbNoTCHBlockingDescription: This indicator provides the radio failures during the TCH assignment procedureFormula: AssFailbyMess (a) SuccAssProbNoTCHBlocking = 1 − AssAtt - TCHLossUsed param.: AssAtt(0(a)), TCHLoss (4.2(a)), AssFailbyMess (4.2(b))Elem. Object: CellUnit NoneRemarks: The indicator only considers radio failures but no TCH losses (blockings) during the assignment procedure, i.e. it is assumed that enough TCH resources are available29 A30808-X3247-B912-1-7618
  30. 30. Information PM: SBS Key Performance IndicatorsSystem5 Call Setup AnalysisThe KPIs of the previous sections are mainly used for the derivation of the Call SetupSuccess Rate (CSSR) and Call Setup Failure Rate (CSFR). The Call Setup SuccessRate and Call Setup Failure Rate are related to the Mobile Station point of view, bymeaning they will count the events related to Mobile Stations.Overview Call Setup AnalysisCS (5.3) CSSR Call Setup Success Rate BSS (5.5) CSFR Call Setup Failure Rate Call Setup Failure Rate due to Immediate Assignment Losses Call Setup Failure Rate due to AGCH Loss Call Setup Failure Rate due to Immediate Assignment without MS Seizure Call Setup Failure Rate due to SDCCH Drops Call Setup Failure Rate due to SSS Procedure Failure Call Setup Failure Rate due to TCH Loss Call Setup Failure Rate due to Assignment Failures by Message Call Setup Failure Rate due to Assignment Failures with other Reasons Call Setup Failure Rate due to Queuing FailuresComparable Overview can also be done for the ‘Number Related KPIs’This chapter contains the following ‘Number related’ KPIs:• Number of Call Setup Attempts• Number of Successful Call Setups• Number of Call Setup FailuresAnd the following ‘Rate related’ KPIs:• Call Setup Success Rate• Call Setup Failure Rate30 A30808-X3247-B912-1-7618
  31. 31. Information PM: SBS Key Performance IndicatorsSystem5.1 Number of Call Setup AttemptsLong name: (a) Number of Call Setup AttemptsShort name: (a) CSAttDescription: This indicator counts all attempts at the BSS to setup up an end to end connection. The indicator deals with the call setup attempts from the perspective of the MSFormula: ImmAssSuccCS (a) CSAtt = ImmAssSuccRateUsed param.: ImmAssSuccCS (3.1a), ImmAssLossRate (2.6a), AGCHLossRate (2.7a), ImmAssNoSeizRate (2.8a)Elem. Object: CellUnit: NoneRemarks: Phantom RACHs are channel required messages not foreseen for the observed cell. The Immediate Assignment procedure to allocate an SDCCH/TCH is then started, but will not be successful, because no MS will reply with a SABM message and therefore a BTS Timer will expire. Phantom RACHs are not considered as call setup attempts. Systematic error A mobile station may also not answer to an IMM ASS Command due to bad radio conditions. Such radio events will not be considered as call setup attempts Be aware of parameter settings for RACHBT and RXLEVAMI The Immediate Assignment failures are independent to the different call types (MOC, MTC, Locupd, SMS, ...). Therefore the Immediate Assignment Failure Rates for any call type are used in the above formula.5.2 Number of Successful Call SetupsLong name: (a) Number of Successful Call SetupsShort name: (a) CSSuccDescription: This indicator counts all successful Call Setups at the BSS to setup up an end to end connection. A Call Setup was successful if the MS was able to seize a TCH.Formula: (a) CSSucc = AssSuccUsed param.: AssSucc (4.3a)Elem. Object: CellUnit: NoneRemarks: Assignment of SDCCH are not considered31 A30808-X3247-B912-1-7618
  32. 32. Information PM: SBS Key Performance IndicatorsSystem5.3 Call Setup Success RateLong name: (a) Call Setup Success Rate (b) Call Setup Success Rate BSSShort name: (a) CSSuccRate (b) CSSuccRateBSSDescription: This indicator will give you the BSS observed Call Setup Success Rate to setup up an end to end connection. Two indicators are available, one that takes into account all Call Setup rejections (BSS immediate assignment, SSS security and TCH assignment), one that only takes into account BSS related Call Setup rejections (BSS immediate assignment and TCH assignment).Formula: (a) CSSuccRate = ImmAssSucc Rate * SSSProcSuc cRateCStot al * AssSuccRat e (b) CSSuccRateBSS = ImmAssSuccRate * ( 1 - SDCCHDropRateCS) * AssSuccRateUsed param.: ImmAssSuccRate (2.11(a)), SSSProcSuccRateCStotal (3.6(b)), AssSuccRate (4.5(a)), SDCCHDropRateCS (3.4(a))Elem. Object: CellUnit: NoneRemarks: BR7: correction CSSuccRateBSS: factor (1-SDCCHDropRateCS) included in formula BR7: KPI CSSuccRateSSS cancelled (just another name for KPI SSSProcSuccRateCStotal (3.6(b)) Systematic errors can occur as described in the used KPIs.5.4 Number of Call Setup FailuresLong name: (a) Number of Call Setup Failures (b) Number of Call Setup Failures due to Immediate Assignment Losses (c) Number of Call Setup Failures due to AGCH Loss (d) Number of Call Setup Failures due to Immediate Assignment without MS Seizure (e) Number of Call Setup Failures due to SDCCH Drops (f) Number of Call Setup Failures due to SSS Procedure Failure (g) Number of Call Setup Failures due to TCH Loss (h) Number of Call Setup Failures due to Assignment Failures by Message (i) Number of Call Setup Failures due to Assignment Failures with other Reasons (j) Number of Call Setup Failures due to Queuing FailuresShort name: (a) CSFail (b) CSFailImmAssLoss (c) CSFailAGCHLoss (d) CSFailImmAssNoSeiz32 A30808-X3247-B912-1-7618
  33. 33. Information PM: SBS Key Performance IndicatorsSystem (e) CSFailSDCCHDrop (f) CSFailSSSProcFail (g) CSFailTCHLoss (h) CSFailAssFailbyMess (i) CSFailAssFailOther (j) CSFailQueFailDescription: These indicators will give you the number of unsuccessful Call Setups. Different indicators distinguish between different causes used in the different procedures (Immediate Assignment, SSS Procedures and Assignment).Formula: (a) CSFail = CSAtt - CSSucc (b) CSFailImmAssLoss = CSAtt * ImmAssLossRate (c) CSFailAGCHLoss = CSAtt * AGCHLossRate (d) CSFailImmAssNoSeiz = CSAtt * ImmAssNoSeizRate (e) CSFailSDCCHDrop = CSAtt * ImmAssSuccRate * SDCCHDropRateCS (f) CSFailSSSProcFail = CSAtt * ImmAssSuccRate * SSSProcFailRateCS (g) CSFailTCHLoss = TCHLoss (h) CSFailAssFailbyMess = AssFailbyMess (i) CSFailAssFailOther = AssFailOther (j) CSFailQueFail = QueFailUsed param.: CSAtt (5.1(a)), CSSucc (5.2(a)), ImmAssLossRate(2.8(a)), AGCHLossRate(2.9(a)), ImmAssNoSeizRate(2.10 (a)), ImmAssSuccRate (2.11(a)), SDCCHDropRateCS(3.4(a)), SSSProcFailRateCS(3.5(a)), TCHLoss(4.2 (a)), AssFailbyMess(4.2(b)), AssFailOther(4.2(c)), QueFail(4.2(c))Elem. Object: CellUnit: NoneRemarks: See remarks in the referenced KPIs33 A30808-X3247-B912-1-7618
  34. 34. Information PM: SBS Key Performance IndicatorsSystem5.5 Call Setup Failure RateLong name: (a) Call Setup Failure Rate (b) Call Setup Failure Rate due to Immediate Assignment Losses (c) Call Setup Failure Rate due to AGCH Loss (d) Call Setup Failure Rate due to Immediate Assignment without MS Seizure (e) Call Setup Failure Rate due to SDCCH Drops (f) Call Setup Failure Rate due to SSS Procedure Failure (g) Call Setup Failure Rate due to TCH Loss (h) Call Setup Failure Rate due to Assignment Failures by Message (i) Call Setup Failure Rate due to Assignment Failures with other Reasons (j) Call Setup Failure Rate due to Queuing FailuresShort name: (a) CSFailRate (b) CSFailRateImmAssLoss (c) CSFailRateAGCHLoss (d) CSFailRateImmAssNoSeiz (e) CSFailRateSDCCHDrops (f) CSFailRateSSSProcFail (g) CSFailRateTCHLoss (h) CSFailRateAssFailbyMess (i) CSFailRateAssFailOther (j) CSFailRateQueFailDescription: These indicators will give you the Call Setup Failure Rate. Different indicators distinguish between different causes used in the different procedures (Immediate Assignment, SSS Procedures and Assignment).Formula: (a) CSFailRate = 1 – CSSuccRate (b) CSFailRateImmAssLoss = ImmAssLossRate (c) CSFailRateAGCHLoss = AGCHLossRate (d) CSFailRateImmAssNoSeiz = ImmAssNoSeizRate (e) CSFailRateSDCCHDrops = SDCCHDropRateCS (f) CSFailRateSSSProcFail = SSSProcFailRateCS (g) CSFailRateTCHLoss = TCHLossRate (h) CSFailRateAssFailbyMess = AssFailbyMessRate (i) CSFailRateAssFailOther = AssFailOtherRate (j) CSFailRateQueFail = QueFailRateUsed param.: CSSuccRate (5.3(a)), ImmAssLossRate(2.8(a)), AGCHLossRate(2.9(a)), ImmAssNoSeizRate(2.10(a)), SDCCHDropRateCS(3.4(a)), SSSProcFailRateCS(3.5(a)), TCHLossRate(4.4(a)), AssFailbyMessRate(4.4(b)), AssFailOtherRate(4.4(c)), QueFailRate(4.4(d))Elem. Object: CellUnit: NoneRemarks: See remarks in the referenced KPIs34 A30808-X3247-B912-1-7618
  35. 35. Information PM: SBS Key Performance IndicatorsSystem6 TCH Drop related Performance Indicators6.1 Number of Dropped TCH ConnectionsLong name: (a) Number of Dropped TCH ConnectionsShort name: (a) TCHDropDescription: This indicator will give you the number of dropped TCH connections related to Mobile Stations. Only drops related to the BSS including the radio interface are considered. But drops detected by the MSC call processing reasons are excluded. (Therefore among others drops arising from the remote BSS and the remote radio interface are not considered)Formula: (a) TCHDrop = NRCLRREQ[1.. 3, 5.. 12, 14 ..18]Use case: Observation of customer satisfactionUsed param.: NRCLRREQ[1 .. 3, 5.. 12, 14 ..18]Elem. Object: CellUnit: NoneRemarks: TCH drops during pending incoming inter BSC handover are not counted in the measurement NRCLRREQ. This avoids double counting of drops during pending HO (during pending HO the TCH drops are only counted in the originating cell). Therefore NRCLRREQ in fact counts the number of dropped TCH calls from the perspective of the Mobile Station (customer dissatisfaction) There is a small systematic error in case of expiry of timer T_MSRFPCI during assignment; in that case NRCLRREQ (“Radio interface message failure”) is triggered. This can only occur when T_MSRFPCI is not well adjusted (< T10). Remark: in case of expiry of T10 the BSC sends ASS FAIL to the MSC in that case NRCLRREQ is not triggered35 A30808-X3247-B912-1-7618
  36. 36. Information PM: SBS Key Performance IndicatorsSystem6.2 TCH Drop DistributionLong name: (a) TCH drop distribution due to expiry of timer T200 (b) TCH drop distribution due to unsolicited DM response (c) TCH drop distribution due to sequence error (d) TCH drop distribution due to expiry of timer T_MSRFPCI (e) TCH drop distribution due to distance limit exceeded (f) TCH drop distribution due to handover access failures (g) TCH drop distribution due to radio link failures (h) TCH drop distribution due to remote transcoder failures (i) TCH drop distribution due to other connection failures (j) TCH drop distribution due to intra cell handovers (k) TCH drop distribution due to inter cell intra bsc handovers (l) TCH drop distribution due to inter bsc handovers (m) TCH drop distribution due to equipment failure (n) TCH drop distribution due to protocol error (o) TCH drop distribution due to distance error (p) TCH drop distribution due to preemption (q) TCH drop distribution due to O&M intervention (r) TCH drop distribution due to other reasonsShort name: (a) TCHDropDist.T200 (b) TCHDropDist.UnsolDMRes (c) TCHDropDist.SeqErr (d) TCHDropDist.TMSRFPCI (e) TCHDropDist.Distance (f) TCHDropDist.HOAccess (g) TCHDropDist.RadLinkFail (h) TCHDropDist.RemTranscFail (i) TCHDropDist.ConnOther (j) TCHDropDist.IntraCellHO (k) TCHDropDist.InterCellHO (l) TCHDropDist.InterBSCHO (m) TCHDropDist.EquipFail (n) TCHDropDist.ProtErr (o) TCHDropDist.DistErr (p) TCHDropDist.Preempt (q) TCHDropDist.OAM (r) TCHDropDist.OtherDescription: This indicator will give you the TCH Drop Distribution showing the particular TCH drops related to the total number of drops related to TCH connections.Use case: Detection of network problems: e.g. insufficient coverage For network optimization normally additional KPIs would be considered, e.g. KPIs for the supervision of transmission power, interference and HO)36 A30808-X3247-B912-1-7618
  37. 37. Information PM: SBS Key Performance IndicatorsSystemFormula: NRFLTCH[1, 10,19,28] (a) TCHDropDis t.T200 = TCHDrop NRFLTCH[2, 11,20,29] (b) TCHDropDist.UnsolDMRes = TCHDrop NRFLTCH[3,12,21,30] (c) TCHDropDist.SeqErr = TCHDrop NRFLTCH[4, 13,22,31] t.TMSRFPCI = (d) TCHDropDis TCHDrop NRFLTCH[5, 14,23,32] (e) TCHDropDist.Distance = TCHDrop NRFLTCH[6, 15,24,33] (f) TCHDropDist.HOAccess= TCHDrop NRFLTCH[7,16,25,34] (g) TCHDropDist.RadLinkFail = TCHDrop NRFLTCH[8,17,26,35] (h) TCHDropDist.RemTranscFail = TCHDrop NRFLTCH[9, 18,27,36] t.ConnOthe = (i) TCHDropDis r TCHDrop UNIHIALC[1 ] (j) TCHDropDist.IntraCellHO = TCHDrop UNIHIRLC[1 ] (k) TCHDropDist.InterCellHO = TCHDrop InterBSCHODrop (l) TCHDropDist.InterBSCHO = TCHDrop NRCLRREQ[1 ,10] (m) TCHDropDist.EquipFail = TCHDrop (n) TCHDropDis NRCLRREQ[5,14] t.ProtErr = TCHDrop (o) TCHDropDis NRCLRREQ[6,15] t.DistErr = TCHDrop (p) TCHDropDis NRCLRREQ[7,16] t.Preempt = TCHDrop (q) TCHDropDist.OAM = NRCLRREQ[8,17] TCHDrop (r) TCHDropDist.Other = NRCLRREQ[9,18] TCHDropUsed param.: NRFLTCH[1..36], UNIHIALC[1], UNIHIRLC[1], InterBSCHODrop(0(a)), TCHDrop(6.1(a)), NRCLRREQ [1..18]Elem. Object: CellUnit: NoneRemarks: Handover Access failures are included in formulas TCHDropDist.HOAccess and37 A30808-X3247-B912-1-7618
  38. 38. Information PM: SBS Key Performance IndicatorsSystem TCHDropDist.InterBSCHO. TCH drops during pending incoming inter BSC handover are not counted in formulas TCHDropDist.HOAccess. This avoids double counting of drops during pending HO (during pending HO the TCH drops are only counted in the originating cell). Therefore NRCLRREQ in fact counts the number of dropped TCH calls from the perspective of the Mobile Station (customer dissatisfaction) If the feature SDCCH Handover is activated, then this will lead to a systematic error.38 A30808-X3247-B912-1-7618
  39. 39. Information PM: SBS Key Performance IndicatorsSystem6.3 TCH Drop RateLong name: (a) TCH Drop RateShort name: (a) TCHDropRateDescription: This indicator will give you the rate of all drops of TCH connections. Drops comprise all BSC caused terminations of TCH connection. I.e. connection termination induced by an MSC is not counted as TCH drop within the scope of the present radio network related document. The TCH drops are related to all seizures of a TCH in the observed cell. A TCH may be seized during call setup and additionally for handover (including Directed Retry). Therefore on call in the view of a mobile subscriber may cause the seizure of more than one TCH spread over several cellsFormula: TCHDrop (a) TCHDropRate = SUCTCHSE[1..2]Used param.: TCHDrop(6.1(a)), SUCTCHSE[1..2]Elem. Object: CellUnit: NoneRemarks: Please note that there can be systematic errors caused by timer settings (Ny, T3105, TTrau, TSync, T_MSRFPCI, T8). If the feature SDCCH Handover is activated, then this will lead to a systematic error. This KPI is not only related to Call Setups. It is related to any TCH seizure (e.g. incoming Handovers). Therefore for network optimization it is recommended to use KPI ‘TCH Drops per Erlanghour ‘, because increasing number of Handovers (e.g. Ping Pong Handovers) will decrease the TCH Drop Rate.39 A30808-X3247-B912-1-7618
  40. 40. Information PM: SBS Key Performance IndicatorsSystem6.4 Call Drop RateLong name: (a) Number of terminated calls (b) Call Drop RateShort name: (a) NumTermCalls (b) CallDropRateDescription: This indicator provides the number of terminated calls and the call drop rate from the view of the MS (customer satisfaction). Preconditions: 1. A call is established when the MS has seized the TCH • Ass Failure in connection with a following Clear Command is not considered as call, since the MS has not yet seized a TCH. (e.g. AssFail: No radio resource available, MSC controlled Directed Retry) • Queuing timer expiry is not considered • Expiry of timer T_MSRFPCI is not considered 2. Call termination (and especially call drop) is counted for that cell, where the TCH was seized by the MS at the time of the call termination (especially call drop) • Call termination (and especially call drop) during pending HO is counted for the old cell 3. Only call drops initiated by the BSS are considered • Drops comprise all BSC caused terminations of calls. I.e. call termination induced by an MSC is not counted as call drop within the scope of the present radio network related document • Release of TCH in connection with HO reversion to old cell is not considered (e.g.: Inter BSC HO -> HO access failure -> Clear Command). Reason: no TCH drop from the MS perspective. •Formula: (a) NumTermCalls = NRCLRCMD[1.. 2, 4 .. 8, 10 ..12] - NRCLRREQ[4,13] - TASSFAIL[6.. 8,11..13] TCHDrop (b) CallDropRate = NumTermCallsUsed param.: TCHDrop(6.1(a)), NRCLRCMD[1 .. 2, 4 .. 8, 10..12], TASSFAIL[6.. 8,11 .. 13], NRCLRREQ[4,13], NumTermCalls(6.4(a))Elem. Object: CellUnit: NoneRemarks: Remark for understanding the formula on the number of terminated calls: Clear Commands may also be received by the MSC at call state when the MS has not yet seized the TCH during TCH assignment, i.e. when no call is yet established. Therefore the following cases are not considered as established calls: • No TCH available after Queuing: In that case the BSC sends Clear Request (“Radio resource not available”) which triggers40 A30808-X3247-B912-1-7618
  41. 41. Information PM: SBS Key Performance IndicatorsSystem NRCLRREQ[4,13]; this also lead to triggering of NRCLRCMD[1,7] (“BSS initiated”) • Unsuccessful TCH Assignment Procedure with Loss of ASSIGNMENT COMMAND (T10 Expiry): In that case the BSC sends Assignment Failure to the MSC and triggers TASSFAIL[6,11]; this also leads to triggering of NRCLRCMD[2,8] (“Call Control”) • Unsuccessful Directed Retry, Intra-BSC, with Reversion to SDCCH (T3124 Expiry): In that case the BSC sends Assignment Failure to the MSC and triggers TASSFAIL[7,12]; this also leads to triggering of NRCLRCMD[2,8] (“Call Control”) • No TCH available (no queuing): In that case the BSC sends Assignment Failure to the MSC and triggers TASSFAIL[8,13]; this also leads to triggering of NRCLRCMD[2,8] (“Call Control”) Systematic failures in the formulas: • Inter BSC handover with reversion to old cell: In that case the MSC receives HO_Failure from the old BSC and sends Clear Command (“equipment failure”) the target BSC which triggers NRCLRCMD[4] for the target cell -> this effect slightly improve the CallDropRate by pretending that more call have existed than in reality. • Inter BSC directed retry with no successful TCH seizure: In that case the BSC send assignment Failure and triggers Tassfail[9,14]; this lead also to a Clear Command (“Call Control”) which triggers NRCLRCMD[2] -> this effect slightly improve the CallDropRate by pretending that more call have existed than in reality. • Expiry of timer T_MSRFPCI during assignment: In that case NRCLRREQ is triggered. This can only occur when T_MSRFPCI is not well adjusted (< T10) -> this effect slightly deteriorates the call drop rate (numerator and denominator are increased) • There can be systematic errors caused by timer settings (Ny1, T3105, TTrau, TSync, T_MSRFPCI, T8). If the feature SDCCH Handover is activated, then this will lead to a systematic error. -> this effect slightly deteriorates the call drop rate (numerator and denominator are increased) Recommendation: Drop per Erlang/hour is recommended to be used for quality assessment of radio network performance. Reason: the call drop rate is depending on the average call duration. The call drop rate is proportional to the call duration.41 A30808-X3247-B912-1-7618

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