South Korea, Seoul & Busan, 2021

Audit Report.

Foreword

For the inhabitants of the denselypopulated Seoul and Busan areas inSouth Korea, it is particularlyinteresting to see how the operatorsperform in their home cities.Therefore, we have performedindividual analyses for the twolargest South Korean metropolitanareas.

More than 13 million (or 25% percent of all) South Koreans live in one of the two largest urban areas of the country. Therefore we have taken a closer look at the individual resultsof Seoul and Busan.

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The leader in mobile benchmarking, umlaut, has analyzed

the mobile networks in South Korea with regards to 5G

mobile network performance.

We measure smartphone data performance based on

extensive drivetests.

As the de-facto industry standard, our benchmarking

methodology focuses on customer-perceived network

quality and covers a wide range of mobile services.

Today, more than 200 mobile networks in more than 120

countries are being evaluated by our unique methodology.

It allows a technical analysis that is unprecedented in its

level of detail and enables comparisons between the net-

work performance and capability of each mobile network.

Our benchmarks help network operators to demonstrate

how well they are delivering wireless connections to

consumers, business users and enterprises and reveals the

areas of improvement.

Testing areaIntro

2070 kmmeasuring distance

Busan

Seoul

Drivetest Voice Data

Device Samsung Galaxy S21+ 5G (Exynos) SM-G996N Samsung Galaxy S21+ 5G (Exynos) SM-G996N

Test Cases Mobile-to-MobileSide1 (5G pref) to Side2 (5G pref) 115 sec call window70 sec call duration15 sec call setup timeoutMulti-RAB traffic injection on both sides

Data 5G preferredHTTP DL datastream 7sHTTP UL datastream 7sHTTP 10MB DL fixed file transferHTTP 5MB UL fixed file transferWeb Browsing - Kepler ETSI Ref. Page10 Live web pages 3 YouTube ( videos ~ 45s)

Mobility andRoute Types 100% Drivetest

Samples ~ 5,735 ~ 58,000

Dates 10 measurement days; 22.07.2021 – 04.08.2021

The map shows the total driving area for South Korea.

The routes were independently selected by umlaut based

on the official coverage maps provided by the network

operators.

5G Coverage Maps LG U+:http://www.uplus.co.kr/css/iner/RetrieveCoverMapNoneSSL.hpi

5G Coverage Maps KT:https://coverage.kt.com/

5G Coverage Maps SKT:http://www.sktcoverage.com/

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Available Frequency SpectrumFor LTE and 5G NR

The graph shows the maximum amount of frequency spectrum available for the respective technology, based on all obser-

ved File DL use cases. The actual amount of frequency spectrum available for a particular File Download can be (a) a

combination of the LTE and NR resources and (b) lower than the maximum owing to shared resources or spectrum availability.

120LTE Spectrum

0

NR Spectrum

SKT

75

SKT

100

KT

55

LG U+

50

KT

100

LG U+

80

[MH

z]

LTE NR Cband

LG U+ 3CA:50Mhz 80Mhz

SKT 5CA:75Mhz 100Mhz

KT 4CA:55Mhz 100Mhz

The table shows the maximum amount of frequency spectrum and LTE carrier aggregation available per operator, based

on all observed File DL use cases.

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Total Score Overall results

Score achieved in Seoul by the networks under test. Score achieved in Busan by the networks under test.

Total Score - Seoul1000 Dots

KT

589

382

SKT

586

346

- S

how

n to

tal s

core

s ar

e ro

und

ed.

LG U+

585

394

Voicemax. 400

Datamax. 600

Operator

979 971932

Total Score - Busan1000 Dots

KT

583

381

SKT

592

339

- S

how

n to

tal s

core

s ar

e ro

und

ed.

LG U+

580

375

Voicemax. 400

Datamax. 600

Operator

955 964931

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5G AvailabilityMeasured from UE

The graph shows the 5G availability measured in Seoul and Busan. All data sequences from the umlaut use case are taken

into account.

100Seoul

[%]

0

Busan

SKT

86.4

SKT

71.6

KT

86.6

LG U+

98.9

KT

86.5

LG U+

85.9

The table shows the 5G availability measured in Seoul and Busan. All data sequences from the umlaut use case are taken

into account.

5G availability is defined as the share of time a user is actually using the 5G network (represented by the percentage of

test cases during which the UE was using 5G).

Technology List Unit LG U+ KT SKT

Seoul

NR [%] 0 0 0

5G [%] [%] 98.85 86.63 86.42

5G-LTE Mixed Session [%] 0.9 13.22 13.41

LTE [%] 0.25 0.15 0.17

Busan

NR [%] 0 0 0

5G [%] 85.9 86.51 71.62

5G-LTE Mixed Session [%] 13.62 13.08 27.4

LTE [%] 0.48 0.41 0.97

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5G User ExperienceHow 5G NR contributes to the overall end-user download throughput

The chart shows the estimated contribution of 5G NR to the overall achieved Avg. Download Throughput in Seoul and

Busan, based on the proportion of LTE and NR PDSCH data rates on all sequences with full NR activity. (Avg. Throughput

in lighter shade, 5G Contribution to Avg. Throughput in darker shade.)

The table shows the estimated contribution of 5G NR to the overall achieved Avg. Download Throughput in Seoul and

Busan, based on the proportion of LTE and NR PDSCH data rates on all sequences with full NR activity.

KPI Name Unit LG U+ KT SKT

Avg. ThroughputSeoul [Mbit/s] 741.640 580.788 725.349

Busan [Mbit/s] 525.126 566.939 693.178

5G Contribution to Avg. Throughput

Seoul [Mbit/s] 603.851 580.739 542.014

Busan [Mbit/s] 425.480 566.896 536.437

542.0 536.4580.7603.9

566.9

425.5

750

[Mbi

t/s]

0 SKT SKTKTLG U+ KTLG U+

Seoul Busan

725.3693.2

580.8

741.6

566.9525.1

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5G User ExperienceHow 5G NR contributes to the overall end-user upload throughput

The chart shows the estimated contribution of 5G NR to the overall achieved Avg. Upload Throughput in Seoul and Busan,

based on the proportion of LTE and NR bearer throughputs on all sequences with full NR activity. (Avg. of UL Throughput

in lighter shade, Avg. NR Contribution of UL Throughput in darker shade.)

The table shows the estimated contribution of 5G NR to the overall achieved Avg. Upload Throughput in Seoul and Busan,

based on the proportion of LTE and NR bearer throughputs on all sequences with full NR activity.

KPI Name Unit LG U+ KT SKT

Average of UL Throughput Seoul [Mbit/s] 95.082 77.148 113.643

Busan [Mbit/s] 62.169 69.341 110.679

Average NR Contribution of UL Throughput

Seoul [Mbit/s] 56.108 77.148 83.376

Busan [Mbit/s] 23.325 69.334 82.343

83.4 82.377.177.1

56.1

23.3

115

[Mbi

t/s]

0 SKT SKTKTLG U+ KTLG U+

Seoul Busan

113.6 110.7

95.1

69.3

69.3

62.2

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Avg., P90 and P10 Throughputs

The graph shows the Session Reliability measured in Seoul and Busan. All data sequences from the umlaut use case are

taken into account

100

[%]

0 SKT

100

SKT

100

KT

100

LG U+

100

KT

100

LG U+

99.8

Seoul Busan

1054.6

897.5841.6

1047.6

843.7

730.7

1100

[Mbi

t/s]

0 SKT

415.8

SKT

424.8

KT

336.9

LG U+

438.8

KT

307.8

LG U+

290.6

714.8654.0

576.3

736.1

561.6515.6

Seoul Busan

Datastream Download Session Reliability

The graph shows the qualified data stream 10 % (Mbps, darker shade), the average throughput (lighter shade) and the

qualified data stream 90 % (Mbps, lightest shade) measured in Seoul and Busan. All data sequences from the umlaut use

case are taken into account.

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Datastream UploadSession Reliability

Avg., P90 and P10 Throughputs

100

[%]

0 SKT

99.9

SKT

100

KT

100

LG U+

100

KT

99.8

LG U+

100

Seoul Busan

142.5

96.5

118.7

94.487.4

54.164.2

54.1

67.5

32.926.4

150

[Mbi

t/s]

0 SKT SKTKTLG U+ KTLG U+

Seoul Busan

112.8105.7

143.9

76.7

94.6

68.860.7

The graph shows the Session Reliability measured in Seoul and Busan. All data sequences from the umlaut use case are

taken into account

The graph shows the qualified data stream 10 % (Mbps, darker shade), the average throughput (lighter shade) and the

qualified data stream 90 % (Mbps, lightest shade) measured in Seoul and Busan. All data sequences from the umlaut use

case are taken into account.

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10Mb File Download Session Reliability

Overall Session Time

100

[%]

0 SKT

100

SKT

100

KT

100

LG U+

100

KT

99.8

LG U+

100

Seoul Busan1

[s]

0 SKT

0.8

SKT

0.6

KT

0.7

LG U+

0.5

KT

0.9

LG U+

0.8

Seoul Busan

The graph shows the Session Reliability measured in Seoul and Busan. All data sequences from the umlaut use case are

taken into account.

The graph shows the Overall Session Time measured in Seoul and Busan. All data sequences from the umlaut use case

are taken into account.

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5Mb File Upload Session Reliability

Overall Session Time

The graph shows the Session Reliability measured in Seoul and Busan. All data sequences from the umlaut use case are

taken into account.

The graph shows the Overall Session Time measured in Seoul and Busan. All data sequences from the umlaut use case

are taken into account.

100

[%]

0 SKT

100

SKT

100

KT

100

LG U+

100

KT

100

LG U+

100

Seoul Busan1.5

[s]

0 SKT

0.9

SKT

0.9

KT

1.0

LG U+

0.8

KT

1.3

LG U+

1.5

Seoul Busan

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VoiceSpeech Quality

Call Setup Time

The graph shows the Speech Quality measured in Seoul and Busan. All data sequences from the umlaut use case are

taken into account.

The graph shows the Call Setup Time measured in Seoul and Busan. All data sequences from the umlaut use case are

taken into account.

5

[MO

S-LQ

O]

0 SKT

4.4

KT

4.2

LG U+

4.5

SKT

4.4

KT

4.1

LG U+

4.4

Seoul Busan5

[s]

0 SKT

4.4

KT

2.4

LG U+

0.6

SKT

4.5

KT

2.6

LG U+

3.1

Seoul Busan

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Achieved values of all networks under test in each of the relevant Data Key Performance Indicators (KPIs) in Busan from all

collected test samples.

Achieved values of all networks under test in each of the relevant Data Key Performance Indicators (KPIs) in Seoul from all

collected test samples.

Busan KPI Name Unit LG U+ KT SKT

HTTP Web Page DL Smartphone

Qualifier [%] 99,9 99,7 100,0

Overall Session Time [s] 1,6 1,4 1,4

HTTP 10MB DL Smartphone

Qualifier [%] 100,0 99,8 100,0

Overall Session Time [s] 0,8 0,9 0,6

90% faster than [Mbit/s] 65,3 121,9 160,4

10% faster than [Mbit/s] 281,9 191,8 334,7

HTTP 5MB UL Smartphone

Qualifier [%] 100,0 100,0 100,0

Average Session Time [s] 1,5 1,3 0,9

90% faster than [Mbit/s] 16,6 22,7 36,3

10% faster than [kbit/s] 65,1 69,8 87,0

HTTP DL FDTT

Qualifier [%] 99,8 100,0 100,0

10% faster than [Mbit/s] 730,7 843,7 897,5

faster than 5 Mbit/s [%] 99,8 99,8 100,0

faster than 20 Mbit/s [%] 99,5 99,8 100,0

HTTP UL FDTT

Qualifier [%] 100,0 99,8 100,0

10% faster than [Mbit/s] 87,4 94,4 143,9

faster than 5 Mbit/s [%] 99,1 99,7 100,0

faster than 20 Mbit/s [%] 98,0 98,9 100,0

YouTube

Qualifier [%] 100,0 99,7 100,0

Start Time [s] 1,4 1,4 1,4

AVG Resolution [p] 1079,2 1080,0 1080,0

YouTube Live Smartphone

Qualifier [%] 100,0 100,0 100,0

Start Time [s] 2,2 2,0 2,1

AVG Resolution [p] 1080,0 1080,0 1080,0

YouTube 4K Smartphone

Qualifier [%] 98,4 99,7 100,0

Start Time [s] 1,4 1,4 1,4

AVG Resolution [p] 2151,1 2151,9 2155,7

Seoul KPI Name Unit LG U+ KT SKT

HTTP Web Page DL Smartphone

Qualifier [%] 99,7 99,9 99,9

Overall Session Time [s] 1,3 1,3 1,5

HTTP 10MB DL Smartphone

Qualifier [%] 100,0 100,0 100,0

Overall Session Time [s] 0,5 0,7 0,8

90% faster than [Mbit/s] 167,0 133,5 132,1

10% faster than [Mbit/s] 312,5 225,4 223,3

HTTP 5MB UL Smartphone

Qualifier [%] 100,0 100,0 100,0

Average Session Time [s] 0,8 1,0 0,9

90% faster than [Mbit/s] 42,4 41,0 43,4

10% faster than [kbit/s] 79,8 75,3 81,5

HTTP DL FDTT

Qualifier [%] 100,0 100,0 100,0

10% faster than [Mbit/s] 1047,6 841,6 1054,6

faster than 5 Mbit/s [%] 100,0 100,0 100,0

faster than 20 Mbit/s [%] 100,0 100,0 100,0

HTTP UL FDTT

Qualifier [%] 100,0 100,0 99,9

10% faster than [Mbit/s] 118,7 96,5 142,4

faster than 5 Mbit/s [%] 100,0 99,9 100,0

faster than 20 Mbit/s [%] 99,9 99,9 100,0

YouTube

Qualifier [%] 100,0 100,0 99,8

Start Time [s] 1,4 1,3 1,5

AVG Resolution [p] 1077,6 1078,5 1079,9

YouTube Live Smartphone

Qualifier [%] 98,8 100,0 99,8

Start Time [s] 2,1 2,1 2,4

AVG Resolution [p] 1079,9 1080,0 1080,0

YouTube 4K Smartphone

Qualifier [%] 98,8 99,8 99,2

Start Time [s] 1,4 1,4 1,5

AVG Resolution [p] 2151,2 2153,2 2151,2

KPI overview — DataSeoul

Busan

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KPI overview — VoiceSeoul and Busan

Achieved values of all networks under test in each of the relevant Voice Key Performance Indicators (KPIs) for Seoul.

Achieved values of all networks under test in each of the relevant Voice Key Performance Indicators (KPIs) for Busan.

Voice Service Group Unit LG U+ KT SKT

Busan

Qualifier [%] 100,0 100,0 99,9

Call Setup Time (P90) [s] 3,1 2,6 4,5

Speech Quality (P10) [MOS-LQO] 4,5 4,1 4,4

Multirab connectivity [%] 100,0 100,0 99,7

Voice Service Group Unit LG U+ KT SKT

Seoul

Qualifier [%] 99,8 99,8 100,0

Call Setup Time (P90) [s] 0,6 2,4 4,4

Speech Quality (P10) [MOS-LQO] 4,4 4,1 4,4

Multirab connectivity [%] 99,8 99,9 100,0

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Key takeaways

KT achieves the highest score in Busan.

In Busan SKT provides the fastest average download speed.

KT has the highest 5G Availability in Busan.

SKT achieves the highest data score in Busan.

In Seoul, LG U+ achieves the highest umlaut score.

LG U+ has the highest average download speed in Seoul.

LG U+ provides the highest 5G Availability in Seoul.

KT achieves the highest data score in Seoul.

LG U+ has the highest voice per-formance in Seoul, providing the shortest Call Setup Time and a very good speech quality.

Seoul Busan

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umlaut SE

Am Kraftversorgungsturm 3 · 52070 Aachen · Germany

Hakan Ekmen · Chief Executive Officer Telecommunication

cell +49 151 571 33 235 · hakan.ekmen@umlaut.com

www.umlaut.com