RN3701 RN3701 3G RAN NSN Optimization Fundamentals

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RN3701

RN3701 –––– 50A

50A

3G RAN Optimization Fundamentals

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Module Objectives Module ObjectivesModule Objectives Module Objectives

At the end of the module you will be able to:

• Analyze the formulas of important example KPIs from the various KPI

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− + × = ]) 260 1001 [ ] 259 1001 [ ] 0 1001 ([ ]) 1 1001 ([ 100 te success_ra RRC_setup_ C M C M C M C M

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RRC RRCRRC

RRC setup success rate (Example)setup success rate (Example)setup success rate (Example)setup success rate (Example)

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RRC RRCRRC

RRC Setup and Access Complete Ratio NW (Example: RNC_94e) Setup and Access Complete Ratio NW (Example: RNC_94e) Setup and Access Complete Ratio NW (Example: RNC_94e) Setup and Access Complete Ratio NW (Example: RNC_94e)

RRC Setup and Access Complete Ratio [%] over the reporting period.

covers RRC Setup and Access phases (from RRC Connection Request to RRC Connection Setup Complete)

RRC connection is needed also for other purposes than a call (SMS, LU, Detach, etc.)

∑ + + × = [ _ _ _ _ ]) ] _ _ _ ([ 100 o_NW plete_rati access_com

RRC_setup_ RRC CONN SETUP COMP DIRECTED

COMP ACC CONN RRC ∑ − + = ]) _ _ _ _ _ [ ] _ _ _ _ _ [ ] _ _ _ ([ o_NW plete_rati access_com RRC_setup_ CALL EMERG REJ STP CONN RRC DIR AFT COMP SETUP CONN RRC ATT STP CONN RRC ∑ ∑ − + + × = ]) 617 1001 [ ] 259 1001 [ ] 0 1001 ([ ]) 260 1001 [ ] 8 1001 ([ 100 o_NW plete_rati access_com RRC_setup_ C M C M C M C M C M NW – Network perspektive

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RNC_154d RRC Connection Setup and Access Complete Ratio is a good stability indicator.

• Covers RRC Setup and Access phases (From RRC Connection Request to RRC Connection Setup Complete). Note1: RRC connection is needed also for other purposes than a call (SMS, LU, Detach, etc.).

• To get the "user perspective" RRC connection repetitions and cell reselections are excluded in this KPI compared to RNC_94e which is for "network perspective"

RRC Connection Setup and Access Complete RRC Connection Setup and Access CompleteRRC Connection Setup and Access Complete RRC Connection Setup and Access Complete

AFT_DIR ETUP_COMP_ RRC_CONN_S L_RESEL CC_REL_CEL RRC_CONN_A EPEAT ETUP_ATT_R RRC_CONN_S NN_STP_ATT sum(RRC_CO DIRECTED) ETUP_COMP_ RRC_CONN_S MP ONN_ACC_CO (sum(RRC_C * 100 RNC_154d + − − + = © Nokia 2014 RN3701 - RU50 18/08/2015 8

Performance can be poor due the:

• Registration attempts in bad coverage areas. Some UE types have poor performance in weak coverage conditions.

• 2G/3G border areas, not enough hysteresis with parameter settings.

• Idle mode parameterization (UEs camping in the wrong cell)

• Poorly planned RNC borders (Iur causes radio failure)

RG_CALL) TP_REJ_EME RRC_CONN_S AFT_DIR ETUP_COMP_ RRC_CONN_S L_RESEL CC_REL_CEL RRC_CONN_A − + −

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Example: RRC Performance Example: RRC Performance Example: RRC Performance Example: RRC Performance

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- Usage

- Mobility

- Quality

18/08/2015

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RAB Success Ratio (Drop call rate) RAB Success Ratio (Drop call rate)RAB Success Ratio (Drop call rate) RAB Success Ratio (Drop call rate)

Call Drop Rate (CDR) = 1 Call Drop Rate (CDR) = 1 Call Drop Rate (CDR) = 1

Call Drop Rate (CDR) = 1 ---- CSR CSR CSR CSR Types of drops:Types of drops:Types of drops:Types of drops:

Radio link drop

Soft drop, RRC or RAB connection might still survive

UE BTS RNC CN

RRC drop

Hard drop, all RAB drop as well

RAB drop

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RAB Success Ratio (Drop call rate) RAB Success Ratio (Drop call rate)RAB Success Ratio (Drop call rate) RAB Success Ratio (Drop call rate)

Call drop rate (service level measurements M1001) Call drop rate (service level measurements M1001)Call drop rate (service level measurements M1001) Call drop rate (service level measurements M1001)

ures ue_to_fail releases_d eases normal_rel ures ue_to_fail releases_d

CDR

=

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Dropped calls = calls which do not terminate due to one of the following reasons • Normal release • Relocation • Preemption © Nokia 2014 RN3701 - RU50 18/08/2015 12

Possible causes for call drops are e.g. • Lack of coverage

• Interference

• SHO failure

• Missing neighbor

• Relocation failure

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RNC_231d – RAB Success KPI for CS Voice from end user perspective

• RU20 version includes new SRNC, ISHO, GAN and transmission failure counters

RAB Success Ratio, Voice (CSR) RAB Success Ratio, Voice (CSR) RAB Success Ratio, Voice (CSR) RAB Success Ratio, Voice (CSR)

E_BTS IL_CS_VOIC RAB_ACT_FA E_RADIO IL_CS_VOIC RAB_ACT_FA E_IU IL_CS_VOIC RAB_ACT_FA E_GANHO EL_CS_VOIC RAB_ACT_R E_ISHO EL_CS_VOIC RAB_ACT_R _HHO L_CS_VOICE RAB_ACT_RE _P_EMP L_CS_VOICE RAB_ACT_RE _SRNC L_CS_VOICE RAB_ACT_RE VOICE T_COMP_CS_ sum(RAB_AC E_TRANS) IL_CS_VOIC RAB_ACT_FA E_UE IL_CS_VOIC RAB_ACT_FA E_RNC IL_CS_VOIC RAB_ACT_FA E_IUR IL_CS_VOIC RAB_ACT_FA E_BTS IL_CS_VOIC RAB_ACT_FA E_RADIO IL_CS_VOIC RAB_ACT_FA E_IU IL_CS_VOIC RAB_ACT_FA P VOICE_P_EM CT_REL_CS_ *sum(RAB_A 100 100 d 231 RNC_ + + + + + + + + + + + + + + + − =

Covers RAB Active Phase of a call. Probability that call has ended normally after setup has been successful. This is taking into notice just calls which has ended this cell, but might have been started in other cells.

E_TRANS) IL_CS_VOIC RAB_ACT_FA E_UE IL_CS_VOIC RAB_ACT_FA E_RNC IL_CS_VOIC RAB_ACT_FA E_IUR IL_CS_VOIC RAB_ACT_FA E_BTS IL_CS_VOIC RAB_ACT_FA E_RADIO IL_CS_VOIC RAB_ACT_FA E_IU IL_CS_VOIC RAB_ACT_FA + + + + + + +

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RAB RABRAB

RAB Success Ratio, Voice (CSR) (reSuccess Ratio, Voice (CSR) (reSuccess Ratio, Voice (CSR) (re----establishment included)Success Ratio, Voice (CSR) (re establishment included)establishment included)establishment included)

• RNC_5434a - RAB Success Ratio for AMR Voice [%] including RRC Call re-establishment into the formula. Successful re-establishments are considered in the same way as abnormal releases (failures) from end user point of view.

• This KPI is calculated similarly as RNC_231d "RAB Success Ratio, Voice (CSR)" additionally taking into account

RRC Call Re-establishments as "failures" from end user point of view.

This KPI is taking into notice just calls which have successfully reestablished or have ended in this cell, but might have been started in other cells.

• One new counter added to formula compared to RNC_231d – M1006C186 RRC_RE_EST_SUCC_RT

© Nokia 2014 RN3701 - RU50 18/08/2015 14 RT) SUCC EST RE RRC E_TRANS IL_CS_VOIC RAB_ACT_FA E_UE IL_CS_VOIC RAB_ACT_FA E_RNC IL_CS_VOIC RAB_ACT_FA E_IUR IL_CS_VOIC RAB_ACT_FA E_BTS IL_CS_VOIC RAB_ACT_FA E_RADIO IL_CS_VOIC RAB_ACT_FA E_IU IL_CS_VOIC RAB_ACT_FA E_GANHO EL_CS_VOIC RAB_ACT_R E_ISHO EL_CS_VOIC RAB_ACT_R _HHO L_CS_VOICE RAB_ACT_RE _P_EMP L_CS_VOICE RAB_ACT_RE _SRNC L_CS_VOICE RAB_ACT_RE VOICE T_COMP_CS_ sum(RAB_AC RT) SUCC EST RE RRC E_TRANS IL_CS_VOIC RAB_ACT_FA E_UE IL_CS_VOIC RAB_ACT_FA E_RNC IL_CS_VOIC RAB_ACT_FA E_IUR IL_CS_VOIC RAB_ACT_FA E_BTS IL_CS_VOIC RAB_ACT_FA E_RADIO IL_CS_VOIC RAB_ACT_FA E_IU IL_CS_VOIC RAB_ACT_FA P VOICE_P_EM CT_REL_CS_ *sum(RAB_A a RNC_ _ _ _ _ _ _ _ _ 100 100 5434 + + + + + + + + + + + + + + + + + + + + + − =

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Example: Voice CSSR and CSR Example: Voice CSSR and CSRExample: Voice CSSR and CSR Example: Voice CSSR and CSR

• RNC_5434a is the new one with re-establishment included

• RNC_5434a shows lower SR than RNC_231d

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AMR Call Completion Success Rate AMR Call Completion Success Rate AMR Call Completion Success Rate

AMR Call Completion Success Rate –––– RNC_231RNC_231RNC_231RNC_231

Statistics from different networks showing value for RNC_231 – March 2014

99.00 99.50 100.00 100.50

AMR Call Completion Success Rate (RNC_231) (%) AMR Call Completion Success Rate (RNC_231) (%)

238 networks Median (99,61) © Nokia 2014 RN3701 - RU50 18/08/2015 16 95.00 95.50 96.00 96.50 97.00 97.50 98.00 98.50 99.00 1 7 ₁3 1 9 2 5 3 1 3 7 4 3 4 9 5 5 6 1 6 7 7 3 7 9 8 5 9 1 9 7 1 0 3 1 0 9 1 1 5 1 2 1 1 2 7 1 3 3 1 3 9 1 4 5 1 5 1 1 5 7 1 6 3 1 6 9 1 7 5 1 8 1 1 8 7 1 9 3 1 9 9 2 0 5 2 1 1 2 1 7 2 2 3 2 2 9 2 3 5 2 4 1

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- Usage

- Mobility

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CS+PS CS+PS CS+PS

CS+PS MultiRABMultiRABMultiRABMultiRAB

• MultiRAB call means that there is CS and PS calls at the same time for the same RRC

connection.

• Usage of Cell_PCH and URA_PCH increased the rate of Multi RAB cases. Thus monitoring

Multi RAB Setup Success ratio becomes more essential.

• There are not failure counters separately for MultiRAB, same failure counters should be

used as for CS and PS service.

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Updated Updated Updated

Updated MultiRabMultiRabMultiRab KPI’s MultiRab KPI’s KPI’s KPI’s –––– RU30 RU30 RU30 RU30

RNC_741b: CS AMR + PS Multi RAB Setup Success Ratio

• MultiRAB setup success rate covers RAB Setup and Access Phases

• This KPI show success ratio when CN request that a Multi-RAB combination in question to be set up

RNC_742b: CS AMR + PS Multi RAB Success Rate

) _ _ _ _ ( ) _ _ _ _ ( * 100 741 _ PSNRT AMR ATT STP RAB sum PSNRT AMR COMP ACC RAB sum b RNC =

RNC_742b: CS AMR + PS Multi RAB Success Rate

• KPI describes retainability of multi-RAB combination CS AMR + PS NRT and covers RAB Active phase of call ) _ _ _ _ _ _ _ _ ( ) _ _ _ _ ( * 100 742 _ PSNRT AMR FAIL ACT RAB PSNRT AMR COMP ACT RAB sum PSNRT AMR COMP ACT RAB sum b RNC + =

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MultiRAB MultiRABMultiRAB

MultiRAB SignallingSignallingSignallingSignalling

UE BTS RNC SGSN

RRC Connection Establishment

RANAP: RAB Assignment request MGW

AMR call Established

RRC: UL Direct Transfer (Activate PDP Context Request) RANAP: Direct Transfer (Activate PDP Context Request)

RRC: Radio Bearer Setup

RRC: Radio Bearer Setup Complete

RANAP: RAB Assignment Response

RANAP: Direct Transfer (Activate PDP Context Accept)

M1001C700 RAB_STP_ATT_AMR_PSNRT : The number of RAB setup attemps the result of which would be a multi-RAB combination "CS AMR + PS NRT".

Counter updated whenever CN requests that the Multi-RAB combination in question be set up. This is the case when a PS/CS RAB already exists and a CS/PS RAB is set up in addition to it (for the same RRC connection).

M1001C701 RAB_ACC_COMP_AMR_PSNRT : The number of RAB access completed for a multi-RAB combination "CS AMR +1PS NRT".

Counter is updated when the RNC receives a setup complete message from the UE, indicating that the Multi-RAB combination in question is successfully established, and sends a response message to CN indicating that the RAB is successfully established.

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NRT PS Call Established

AMR + NRT PS RAB active

RANAP: RAB Assignment request with IE RAB release

RRC: Radio Bearer Release

RRC: Radio Bearer Release Complete

RANAP: RAB Assignment Response

indicating that the RAB is successfully established. This is the case when a PS/CS RAB already exists and a CS/PS RAB is set up in addition to it (for the same RRC connection).

M1001C702 RAB_ACT_COMP_AMR_PSNRT The number of RAB active completions and active releases for the multi-RAB combination "CS AMR + 1 PS NRT". Counter updated when RAB active is completed for the RAB type in question. Also RAB active releases due to SRNC Relocation, Inter-system handover, Inter-RNC hard handover and pre-emption update this counter.

M1001C703 RAB_ACT_FAIL_AMR_PSNRT The number of RAB active failures for multi RAB combination "CS AMR + PS NRT". Counter updated when one of the RAB in the multi RAB combination in question fails in the active phase of the call.

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Example: Example: Example:

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- Usage

- Mobility

- Quality

18/08/2015

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SHO success rate SHO success rateSHO success rate SHO success rate

UE Node B RNC

RRC: Measurement Report (e1a / e1c)

NBAP: Radio Link Setup Request – for Soft Handover NBAP: Radio Link Addition Request – for Soft Handover

NBAP: Radio Link Setup Response

Decision to setup new RL

Start TX/RX

SHO

ALCAP : ERQ

RRC: Active Set Update Complete

RRC: Active Set Update

NBAP: Radio Link Setup Response NBAP: Radio Link Addition Response

ALCAP : ECF

success rate

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SHO success rate SHO success rateSHO success rate SHO success rate

• KPI checks reliability of SHO only

• Problems like cell overlap or specific adjacencies discussed later • Attempt and success counted in all source cells

_1c t_requests replacemen sts_1b drop_reque equests_1a addition_r t_updates _active_se successful

s_rate

SHO_succes

=

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SHO success rate SHO success rate SHO success rate SHO success rate

FOR_NRT) EQ_ON_SHO_ CELL_DEL_R _FOR_NRT REQ_ON_SHO CELL_REPL_ FOR_NRT EQ_ON_SHO_ CELL_ADD_R FOR_RT EQ_ON_SHO_ CELL_DEL_R _FOR_RT REQ_ON_SHO CELL_REPL_ SHO_FOR_RT DD_REQ_ON_ sum(CELL_A FOR_NRT) ES_ON_SHO_ SUCC_UPDAT SHO_FOR_RT PDATES_ON_ sum(SUCC_U * 100 ate% HOsuccessr RNC_195a_S + + + + + + = RNC_153b SHO SR, RT RNC_192b SHO SR, NRT UE Node B RNC Number of successful AS update for the cell under observation

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REQ_ON_SHO CELL_REPL_ EQ_ON_SHO CELL_DEL_R EQ_ON_SHO CELL_ADD_R ES_ON_SHO SUCC_UPDAT + +

Total number of not periodical measurement report (1A, 1B, 1C) received by the cell under

observation

UPDATED FOR ALL THE CELLS WITHIN as WHEN MEAS. REPORT IS RECEIVED

RRC: Measurement Report (e1a / e1c)

NBAP: Radio Link Setup Request – for Soft Handover

ALCAP : ERQ

RRC: Active Set Update Complete

RRC: Active Set Update

NBAP: Radio Link Addition Request – for Soft Handover NBAP: Radio Link Setup Response NBAP: Radio Link Addition Response

ALCAP : ECF

Decision to setup new RL Start TX/RX

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Example: SHO attempts and success for RT & NRT Example: SHO attempts and success for RT & NRTExample: SHO attempts and success for RT & NRT Example: SHO attempts and success for RT & NRT

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- Usage

- Mobility

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Throughput measurement overview Throughput measurement overviewThroughput measurement overview Throughput measurement overview

cell throughput cell throughputcell throughput cell throughput

HSPA throughput sent / received by RNC on DL / UL per cell

(cell throughput measurements M1023) (e.g. RNC_608c, RNC_739d)

Idea: 60 ATION PERIOD_DUR 1000 8 TA_VOL HS_DSCH_DA RNC at Throughput Average d -MAC HSDPA ⋅ ⋅ ⋅ =

∑

Transmission of MAC-d / MAC-es PDUs over HS-DSCH / E-DCH Counter give data volume in byte

KPI give throughput in Kbit/s

60 ATION PERIOD_DUR 1000 8 TA_VOL SDPA_UL_DA NRT_EDCH_H RNC at Throughput Average es -MAC HSUPA ⋅ ⋅ ⋅ =

∑

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