Survey of Data Network Survey of Data Network Infrastructure Options Infrastructure Options

for Rural Areasfor Rural AreasA Platform for Asynchronous A Platform for Asynchronous

MessagingMessaging

Team Members: Stephane Guerraz, Sukun Kim, Adam Ludwin, Hong Qu, and Tu Tran

Research QuestionsResearch Questions

1) What network architectures can 1) What network architectures can cost-effectively deploy text, voice, cost-effectively deploy text, voice, image, video services using IP, image, video services using IP, asynchronous delivery methods?asynchronous delivery methods?

2) What commercially viable methods 2) What commercially viable methods can support these services?can support these services?

Application: SEWAA case studyApplication: SEWAA case study

Method for evaluating Method for evaluating sustainabilitysustainability

Demand for ICT

Cost Estimator

Network costKiosk costSetup costOperating cost

ApplicationServices

Revenue Model

Income levelUsage freqPop density Savings from ICT

Setup Costs = Software + Hardware + Installation + Training + Depreciation

Operating Costs = Utilities + Telcom Services + Rent + Labor + Advertising

What do we mean by What do we mean by asynchronous delivery asynchronous delivery

methods?methods?

Kiosk

Asynchronous Kiosks

SynchronousNetwork

Kiosk Kiosk

Data Center / ISP

What do we mean by What do we mean by asynchronous delivery asynchronous delivery

methods?methods?

Kiosk

Asynchronous Kiosks

SynchronousNetwork

Kiosk Kiosk

Data Center / ISP

Bandwidth ComparisonBandwidth Comparison

0

50

100

150

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300

350

400

GEO (VSAT) CDMA CorDect Dial-up

MinMax

Calculating cost of NetworkCalculating cost of Network

Operating Costs Set-up Costs

Cost of Network

BandwidthRequirementper village

Distance &Geographic

factor

TrafficEstimator

ApplicationProfile &

population

Total Cost for 5 years vs Bandwidth (zoom)

0

500000

1000000

1500000

2000000

2500000

3000000

2K 4K 8K 16K 32K 64K 128K

Bandwidth Requirement per Village (bps)

Tot

al C

ost

for

5 ye

ars

(Rup

ee)

CDMA(fixed)

CorDECT

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

GEO(VSAT)

CorDECT(existing)

Why collective franchise Why collective franchise model?model?

ScalabilityScalabilitySecuring loan repayment through Securing loan repayment through

collective responsibility (mutuality)collective responsibility (mutuality)Creating peer-pressure to performCreating peer-pressure to performCreating a community of local Creating a community of local

entrepreneurs with exchange of entrepreneurs with exchange of best practicesbest practices

Costs vs RevenuesCosts vs Revenues

Sale per household 100 200 300# households

100 10,000 20,000 30,000

200 20,000 40,000 60,000

300 30,000 60,000 90,000

Average Monthly Sales per Center

Cost Estimator

Setup Costs: 400$ Operating Cost: 50$/mth

ApplicationServices

Revenue Model200$/mth

SewaaSewaa

Month Capital Due Interests Amortization Payment1 23,000 1840.00 3,160.00 5,000.00 2 19,840 1587.20 3,412.80 5,000.00 3 16,427 1314.18 3,685.82 5,000.00 4 12,741 1019.31 3,980.69 5,000.00 5 8,761 700.85 4,299.15 5,000.00

6 4,462 356.92 4,643.08 5,000.00

Loan Payment with revenue=10,000/Mth and I.R.=8%/Mth

Financially

Financially

Sustainabl

Sustainabl

ee

FindingsFindings

Developed a network cost estimatorDeveloped a network cost estimatorDeveloped a revenue-generating Developed a revenue-generating

business modelbusiness modelSynthesized technology costs with Synthesized technology costs with

business model business model Final Product: General guidelines for Final Product: General guidelines for

evaluating rural connectivity projectsevaluating rural connectivity projects

The EndThe End

Challenges of bringing Challenges of bringing connectivity to rural areasconnectivity to rural areas

AreaArea Unreliable Unreliable

electricityelectricity Limited/non-Limited/non-

existent telecom existent telecom infrastructureinfrastructure

Poor roads Poor roads infrastructure infrastructure

Diverse TopologyDiverse Topology Low village densityLow village density

ResidentsResidents High illiteracy rateHigh illiteracy rate Limited business Limited business

skillsskills Little technology Little technology

skillsskills Lack of access to Lack of access to

capitalcapital

Benefits of asynchronous interaction Benefits of asynchronous interaction at hardware and application levelsat hardware and application levels

HardwareHardware Less power Less power

requirements: less requirements: less energy spent having energy spent having the radio on.the radio on.

Decrease Decrease maintenance costs maintenance costs since down time only since down time only increases delay; it increases delay; it doesn’t disable doesn’t disable serviceservice

Application Level*Application Level* Bandwidth requirement Bandwidth requirement

can be lowercan be lower Decrease network Decrease network

technology coststechnology costs Limits over utilization: Limits over utilization:

more users possible more users possible since full-time access since full-time access does not need to be does not need to be guaranteedguaranteed

* * Our focusOur focus

Satellite (LEO, GEO-VSAT)Satellite (LEO, GEO-VSAT)

Kiosk

Satellite dish

Satellite

Server

InternetSatellite dish

KioskModem

Radio tower

Radio tower

KioskModem

Radio tower

Server

Internet

Wireless -Wireless -CDMACDMA

CorDECTCorDECTWiFiWiFi

WiredWired

KioskModem

Server

Internet

KioskModem

KioskModem

Kiosk

Wireless Technologies (1)Wireless Technologies (1)

LEO MEO GEO GSM CDMA (mobile) CDMA (fixed)Range (Km) N/A [1] N/A [1] N/A [1] 30 [6] 30 [6] 30 [6]Bandwidth (up/down) (bps) 4800 (*1) [3] 400K/40K (*2) [4] 14.4K [6] 13K [6] > 13K [6]Latency (s) 10m [1] 200m [1] 500m [1] < 1m [6] < 1m [6] < 1m [6]Rotation delay 15min [2] 2~4hr [2] N/A N/A N/A N/AFrequency (Hz) Refer 'Frequency Spectrum of Satellite' [2] 800M/900M/1800M/1900M 800M/1900M [7] 800M/1900M [7]Cost (inst) ($) modem 600~1000 (*1) [3] modem 200~300 (*2) [4] per user 701 (*3) [6] per user 205 (*3) / 445 (*4) [6] per user 290 (*4) [6]Cost (month) ($) 70 (*1) [3] 99 (*2) [4] 43 (*3) [6] 26 (*3) / 40 (*4) [6] 35 (*4) [6]Cost (min) ($) 0 (*1) [3] 0 (*2) [4] 0 (*3) [6] 0 (*3, *4) [6] 0 (*4) [6]Energy

Wireless Technologies (2)Wireless Technologies (2)

CorDECT WiFi (802.11) WiMax (802.16) Optical Wired PhoneRange (Km) 25 [11] 38 (*6) [14] 50 (*8) [15] N/A N/ABandwidth (up/down) (bps) 35~70K [12] 11M (*7) [14] 70M (*8) [15] 1.0G 56KLatency (s) < 1m [12] 100~150u [14] < 1m [Estimation] < 1m [Estimation] < 1m [Estimation]Rotation delay N/A N/A N/A N/A N/AFrequency (Hz) 1.9G [12] 2.4G (*7) [14] 3.5G (*8) [15] N/A N/ACost (inst) ($) tower 25,000 [11] tower 200~850 (*6) [14] tower 30,000 / modem 400~500 (*8) [16] 200 NIC [17] / 0.2 per meter [18] end point 800 + line [11]Cost (month) ($) 70 (*5) [13] 0 [14] 0 [16] 0 30~40 [11]Cost (min) ($) 0 (*5) [13] 0 [14] 0 [16] 0 0

Network Cost EstimatorNetwork Cost EstimatorLEO GEO(VSAT)CDMA(fixed) CorDECT CorDECT(existing) WiFi(802.11b) Telephone Telephone(existing) Fiber-optic

Infra install cost 0 0 557234640 8.04E+08 182640 32108112 1.25E+08 182640 93986544Infra maintenance cost 4807998 702022.5 4200811.32 6043192 1093922.28 255513.36 1002054 249623.22 726450.6End point cost 493128 17122.5 13698 6849 6849 6849 54792 684.9 13698

Bandwidth per link 4,800 40,000 13,000 35,000 35,000 11,000,000 56,000 56,000 1,000,000,000Effective bandwidth per link 1920 16000 5200 14000 14000 4400000 22400 22400 400000000

Connection per tower 100 100 1 100 1Cost of tower 25,000 25,000 2,300Radius 30 25 38Cost of wire per Km 400 300

Cost of ISP center 2,000 2,000 2,000 2,000 2,000 2,000 2,000ISP fee per bit 7.14E-05 7.14E-05 7.14E-05 7.14E-05 7.14E-05 7.14E-05Monthly fee for connection 70 100 20 35Cost of modem 800 250 50 50 50 100 800 10 200

Infra install cost# of access point (AP) sites 228 328 142total # of tower 243 351 151total # of connection 107 107Cost of network 6100000 8800000 349600 1369600 1027200Cost of hardware 0 0 6102000 8802000 2,000 351600 1371600 2,000 1029200

Infra maintenance costISP 63000 10000 114.285714 114.2857 15851.85185 114.2857143 114.2857 3.61E+03 114.2857143Hardware maintenance 7200 250 61220 88120 120 3616 14516 30 10492Total cost 70200 10250 61334.2857 88234.29 15971.85185 3730.285714 14630.29 3644.285714 10606.28571

End pointMultiplicity of modem 9 1 4 2 2 1 1 1 1Cost of hardware 7200 250 200 100 100 100 800 10 200

Network Cost Estimator Network Cost Estimator (cont.)(cont.)

4 ?̂ 1 4 16 64 256 1024 4096 16384100 25 6.25 1.5625 0 0 0 0

# of links 80 20 5 2 0 0 0 0# of connections per link

Telephone 2,240,000 2,240,000 2,240,000 2,240,000 2,240,000 2,240,000 2,240,000 2,240,0001 1 1 1 2 8 30 118

107 80 20 5 2 0 0 0 0

Fiber-optic 400,000,000 400,000,000 400,000,000 400,000,000 400,000,000 400,000,000 400,000,000 400,000,0001 1 1 1 1 1 1 1

107 80 20 5 2 0 0 0 0CDMA(fixed)

Connection capacity 520000 520000 520000 520000 520000 520000 520000 520000Load per node 7017.54386 7017.54386 7017.54386 7017.54386 7017.54386 7017.54386 7017.54386 7017.54386connections per link 1 1 1 1 4 14 56 222# of nodes 228 228 228 228 228 228 228 228

228 57 14.25 3.5625 0 0 0 0182 46 11 4 0 0 0 0

243 182 46 11 4 0 0 0 0CorDECT

Connection capacity 1400000 1400000 1400000 1400000 1400000 1400000 1400000 1400000Load per node 4878.04878 4878.04878 4878.04878 4878.04878 4878.04878 4878.04878 4878.04878 4878.04878connections per link 1 1 1 1 1 4 15 58# of nodes 328 328 328 328 328 328 328 328

328 82 20.5 5.125 1.28125 0 0 0263 65 17 4 2 0 0 0

351 263 65 17 4 2 0 0 0WiFi(802.11b)

Connection capacity 4400000 4400000 4400000 4400000 4400000 4400000 4400000 4400000Load per node 11267.60563 11267.60563 11267.60563 11267.60563 11267.60563 11267.60563 11267.60563 11267.60563connections per link 1 1 1 1 1 3 11 42# of nodes 142 142 142 142 142 142 142 142

142 35.5 8.875 2.21875 0 0 0 0112 30 6 3 0 0 0 0

151 112 30 6 3 0 0 0 0

Inputs to Network Cost Inputs to Network Cost EstimatorEstimator

D: average distance to neighboring village32 32 32

V: density of villages = 1 / D 2̂0.000976563 0.000977 0.000977

G: geographic factor (0 ~ 1)0.5 0.5 0.5

B: bandwidth requirement per village16,000 16000 16000

N: total number of villages100 100 100

K: average degree of communication tree4 4 4

Bandwidth factor0.4 0.4 0.4

Infra install cost factor2 2 2

Infra maintenance cost factor1.5 1.5 1.5

End point cost factor1.5 1.5 1.5

Cost vs BandwidthCost vs Bandwidth

Infrastructure Installation Cost vs Bandwidth

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Bandwidth Requirement per Village (bps)

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up

ee

)

LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Infrastructure Installation Cost vs Bandwidth (zoom)

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Bandwidth Requirement per Village (bps)

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Fiber-optic

End-point Installation Cost vs Bandwidth

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LEO

GEO(VSAT)

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CorDECT

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WiFi(802.11b)

Telephone

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Fiber-optic

End-point Installation Cost vs Bandwidth (zoom)

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Bandwidth Requirement per Village (bps)

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CDMA(fixed)

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WiFi(802.11b)

Telephone(existing)

Fiber-optic

Total Installation Cost vs Bandwidth

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LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Total Installation Cost vs Bandwidth (zoom)

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CorDECT(existing)

WiFi(802.11b)

Telephone(existing)

Total Operation Cost vs Bandwidth

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LEO

GEO(VSAT)

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CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Total Operation Cost vs Bandwidth (zoom)

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CorDECT

WiFi(802.11b)

Telephone

Fiber-optic

Total Cost for 5 years vs Bandwidth

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Bandwidth Requirement per Village (bps)

Tot

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ars

(Rup

ee)

LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Total Cost for 5 years vs Bandwidth (zoom)

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Tot

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ost

for

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ars

(Rup

ee)

CDMA(fixed)

CorDECT

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

GEO(VSAT)

CorDECT(existing)

Cost vs DensityCost vs Density

Infrastructure Installation Cost vs Density of Villages

0

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0.001 0.0039 0.0156 0.0625 0.25 1 4

Density of Villages (villages / Km2)

Infr

astr

uctu

re

Inst

alla

tion

Cos

t (R

upee

)

LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Infrastructure Installation Cost vs Density of Villages (zoom)

0

10000000

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0.015625 0.0625 0.25 1 4

Density of Villages (villages / Km2)

Infr

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Inst

alla

tion

Cos

t (R

upee

)

LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

What we didWhat we did

Surveyed various network architectures Surveyed various network architectures using metricsusing metrics

Given the density of villages and the Given the density of villages and the bandwidth requirement, estimated the bandwidth requirement, estimated the cost of each network architecture.cost of each network architecture.

Developed a business model for Developed a business model for sustainability sustainability

Bandwidth Bandwidth Range Range LatencyLatency

Installation cost Installation cost Operating costsOperating costs

End-point Installation Cost vs Density of Villages

0

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0.00098 0.00391 0.01563 0.0625 0.25 1 4

Density of Villages (villages / Km2)

End

-poi

nt I

nsta

llatio

n C

ost

(Rup

ee)

LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

End-point Installation Cost vs Density of Villages (zoom)

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(Rup

ee) GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone(existing)

Fiber-optic

Total Installation Cost vs Density of Villages

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0.00098 0.00391 0.01563 0.0625 0.25 1 4

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GEO(VSAT)

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CorDECT

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WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Total Installation Cost vs Density of Villages (zoom)

0

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0.015625 0.0625 0.25 1 4

Density of Villages (villages / Km2)

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LEO

GEO(VSAT)

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CorDECT

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Telephone

Telephone(existing)

Fiber-optic

Total Operation Cost vs Density of Villages

0

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0.00098 0.00391 0.01563 0.0625 0.25 1 4

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Total Operation Cost vs Density of Villages (zoom)

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0.003906 0.015625 0.0625 0.25 1 4

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Fiber-optic

Total Cost for 5 years vs Density of Villages

0

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0.00098 0.00391 0.01563 0.0625 0.25 1 4

Density of Villages (villages / Km2)

Tot

al C

ost

for

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ars

(Rup

ee)

LEO

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Total Cost for 5 years vs Density of Villages (zoom)

0

50000000

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0.003906 0.015625 0.0625 0.25 1 4

Density of Villages (villages / Km2)

Tot

al C

ost

for

5 ye

ars

(Rup

ee)

GEO(VSAT)

CDMA(fixed)

CorDECT

CorDECT(existing)

WiFi(802.11b)

Telephone

Telephone(existing)

Fiber-optic

Network ModelNetwork Model

Server

Repeater

Repeater

Repeater

Repeater

Repeater Repeater

Repeater

70K35K 35K

140K

Infrastructure Installation Infrastructure Installation CostCost

Given bandwidth requirement per Given bandwidth requirement per village, density of villages, village, density of villages, geographical complexity, total geographical complexity, total number of villagesnumber of villages

Estimate multiplicity of each link in Estimate multiplicity of each link in communication networkcommunication network

Estimate total number of linksEstimate total number of linksAdd data center, installation, Add data center, installation,

administration costadministration cost

File SizesFile Sizes

Text: 700 page book in ASCII = 1 Text: 700 page book in ASCII = 1 MBMB

Voice: 4 minute MP3 = 3.8 MB at Voice: 4 minute MP3 = 3.8 MB at 128 kbs128 kbs

Image: GIF = 500 KB, JPG = 100 KBImage: GIF = 500 KB, JPG = 100 KBVideo: Without compression = 100 Video: Without compression = 100

Mbs, with compression = 45MbsMbs, with compression = 45Mbs*Information from “The Information Economy” research by U.C. Berkeley SIMS *Information from “The Information Economy” research by U.C. Berkeley SIMS

Professor Hal Varian Professor Hal Varian

Case Study: SEWAACase Study: SEWAA

OpportunitiesOpportunities Communication (email, voice/video mail)Communication (email, voice/video mail) Agricultural info and marketingAgricultural info and marketing Provide government servicesProvide government services Tourism revenueTourism revenue Job creation by attracting outsourcing projectsJob creation by attracting outsourcing projects

IssuesIssues Technology phobiaTechnology phobia Lack of relevant content in the local languageLack of relevant content in the local language Business model: connectivity at affordable costBusiness model: connectivity at affordable cost

Case Study: Case Study: SEWAASEWAA

Rural Telecenter in Uttaranchal, IndiaRural Telecenter in Uttaranchal, India Himalayan region: a hostile geography Himalayan region: a hostile geography

Isolated small villages Isolated small villages Mountainous terrainMountainous terrain Poor connectivity for roads and tele-comPoor connectivity for roads and tele-com Unreliable electricityUnreliable electricity

Possible Network TechnologiesPossible Network Technologies Wired phone lineWired phone line Local Wireless Loop (corDECT)Local Wireless Loop (corDECT) SatelliteSatellite

Case Study: SEWAA – What Case Study: SEWAA – What we’ve decidedwe’ve decided

Mountainous terrain precludes Mountainous terrain precludes wireless technology, such as Wi-Fi, wireless technology, such as Wi-Fi, CorDECT, and cellularCorDECT, and cellular

Satellite too expensive at this pointSatellite too expensive at this pointStage 1 network: dial-upStage 1 network: dial-upAsynchronous connectivity – Asynchronous connectivity –

download common files, store and download common files, store and access locally, store and distribute access locally, store and distribute multi-media on CDmulti-media on CD

Member RolesMember Roles

Business AnalysisBusiness Analysis Stephane GuerrazStephane Guerraz Adam LudwinAdam Ludwin

Technology Technology AnalysisAnalysis

Sukun KimSukun Kim Hong QuHong Qu Tu TranTu Tran