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The CATER Initiative Cost-Effective Appropriate Technologies for Emerging Regions. Lakshminarayanan Subramanian Courant Institute of Mathematical Sciences New York University A joint effort with researchers from Courant Institute, NYU School of Medicine, NYU Wagner School of Public Policy.
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The CATER InitiativeCost-Effective Appropriate Technologies for Emerging Regions Lakshminarayanan Subramanian Courant Institute of Mathematical Sciences New York University A joint effort with researchers from Courant Institute, NYU School of Medicine, NYU Wagner School of Public Policy
The CATER Lab Mission: Develop low-cost and appropriate Information and Communication Technologies (ICT) for improving essential services in developing regions around the world • Focus Application Areas • Communications • Healthcare • Micro-finance • Education
The CATER team • Healthcare and Medical Education • Mary Ann Hopkins • Brian Levine • Technology • NYU: • Lakshmi Subramanian • Jinyang Li • Yann Lecun • External collaborators: • Eric Brewer(Berkeley) • Tapan Parikh(Berkeley) • Micro-finance • Jonathan Morduch • Tapan Parikh • Developmental Economics • Yaw Nyarko
Why ICTD Research? • Development Theories • Sachs: Give Aid • Easterly: $50 trillion – nothing much to show • Prahlad: Bottom of the pyramid • Empower Rural Markets (Amartya Sen) • 3-4 billion people with per-capita < US$2,000/year • Could swell to 6-8 billion over the next 25 years • Most live in rural villages or urban slums and shanty towns—movement towards urbanization • Hard to reach, disorganized, and local markets
ICT: A Big Missing Piece • Communications • Awareness, access to external world, phone calls • Healthcare • “Where there is No Doctor?”: Rural healthcare system • Telemedicine/consultation • Continuing Medical Education for Health-workers • Low-cost diagnostic tools • Finance • Microfinance audit, insurance schemes • Education • Educational modules, distance learning • Others • Agriculture, Commerce, Supply chain and E-governance
Network connectivity is key! Traditional wire-line connectivity solutions are not economically viable! Potential options Develop new low-cost connectivity solution! Leverage existing low-bandwidth wireless solutions Cellular, Satellite, CDMA450, WiMax Intermittent links are a fact of life Budget constrained links SMS Power outages Physical transportation links 6
Connectivity options Type of Network Connectivity High b/w (5-10 Mbps) WiLDNet Low b/w (10-80 Kbps) GPRS, Satellite, CDMA, WiMax Intermittent Low b/w Usage constraint SMS Intermittent High delay Bus, Postal network Telemedicine, Distance Learning, Education, Video Teleconsultation, IP Telephony, Web and Cellphone based services Cell-phone Services for Finance Supply Chain Health care Rural Cafes Rural ATMs Bulk content Distribution
Focus Areas • High bandwidth low-cost connectivity • WiRE architecute: An alternative to Cellular • WiLDNet: Wifi-based Long Distance Networks • Multi-Radio Mesh networks • Extending the Web to Rural Areas • Rural Café: Web Access over Intermittent Networks • SMS Find: SMS Search • Contextual Search Portals • Intermittent Mobile Applications • Cell phone based Medical Records • SmartTrack: Drug Tracking System • ATMosphere: Intermittent Rural ATMs
Need for Economic viability • Challenges • Low user densities • Low purchasing power • Satellite • $15K installation + $3K per month /Mbps • Cellular/ WiMax • High Opex. 5-25 cents/min • Wireline solutions • Non starter
Need a new connectivity solution Operational Expenditure is very high for Cellular/WiMax Fiber/WiMax is the least economically viable
Architectural components • Point-to-point WiLDNet links • Point-to-multipoint distribution links • Multi-radio mesh links • A large local cache at each node • Mobile devices as end-points • Why? – 40% rural users own a cellphone in Africa!!!
Challenges • Physical layer • Steerable antennas, better radios, 802.11n? • MAC layer • Unified MAC • Network layer • Naming, Addressing, QoS, routing • Robustness • Power, maintenance • Application layer • Security, End-to-end performance
Overall vision • WiRE architecture – a replacement to the cellular architecture • Significantly lower cost • Much higher bandwidth • Focused coverage • Significantly lower power • Intermittent operations • Economically viable!
WiFi-based Long Distance Networks • WiLD links use standard 802.11 radios • Longer range up to 150km • Directional antennas (24dBi) • Line of Sight (LOS) • Why choose WiFi: • Low cost of $500/node • Volume manufacturing • No spectrum costs • Customizable using open-source drivers • Good datarates • 11Mbps (11b), 54Mbps (11g)
Routers used: (a) Linksys WRT54GL, (b) PC Engines Wrap Boards, Costs: (a) $50, (b) $140 AirJaldi Network • Tibetan Community • WiLD links + APs • Links 10 – 40 Kms • Achieve 4 – 5 Mbps • VoIP + Internet • 10,000 users
Routers used: PC Engines Wrap boards, 266 Mhz CPU, 512 MB Cost: $140 Aravind Eye Hospital Network • South India • Tele-ophthalmology • All WiLD links • Links 1 – 15 Kms long • Achieve 4 – 5 Mbps • Video-conferencing • 3000 consultations/month
New World Record – 382 Kms Pico El Aguila, Venezuela Elev: 4200 meters
Overall Impact • Both networks financially sustainable • 50000 patients/year being scaled to 500000 patients/year • Over 3000 thousand patients have recovered sight
Multi-radio Mesh Networks • Goal: Can we improve wireless throughput using multi-radio mesh networks? • Challenges: • Radio separation constraints • Nodes are very small • Solving routing and channel assignment together • Intra-path interference • Channel losses and highly fluctuating link behavior • Distributed operation
Our multi-radio node • Small nodes • Highly varying link qualities
Our Indoor Testbed • NSC Geode Processors, 128MB RAM, 1GB Flash • Implemented on the Click Modular Router • Patched Madwifi 0.9.3.3
Focus Areas • High bandwidth low-cost connectivity • WiREarchitecute: An alternative to Cellular • WiLDNet: Wifi-based Long Distance Networks • Multi-Radio Mesh networks • Extending the Web to Rural Areas • Rural Café: Web Access over Intermittent Networks • SMS Find: SMS Search • Contextual Search Portals • Intermittent Mobile Applications • Cell phone based Medical Records • SmartTrack: Drug Tracking System • ATMosphere: Intermittent Rural ATMs
Rural Cafes • We Search over intermittent links? • A typical search today involves 4-8 queries! • Can we do web search in one round? • An Intermittent proxy based solution • Change the query interface • Specify all that you know about what you are searching for • Intermittent proxy issues multiple queries, prefetches and bundles response pages • Local proxy enables search within retrieved bundle • Under deployment in Amrita University, India
RuralCafe Basic Idea Local Area Network Internet Intermittent Link Remote Proxy Local Proxy Web Servers Clients
SMSFind • SMS based Contextual Web Search • Google SMS ,Yahoo Onesearch restricted to fixed contexts • SMSFind features • 140 byte useful information extraction engine • Contextual extractors • Works for arbitrary contexts
Contextual Search Portals • How do we setup malaria.google.com? • A portal to search all information about malaria! • Uses of Contextual Portals • Offline web search • Packing the Relevant Web in a Hard Disk • Health portals • Rethinking page-rank within a context?
Focus Areas • High bandwidth low-cost connectivity • WiREarchitecute: An alternative to Cellular • WiLDNet: Wifi-based Long Distance Networks • Multi-Radio Mesh networks • Extending the Web to Rural Areas • Rural Café: Web Access over Intermittent Networks • SMS Find: SMS Search • Contextual Search Portals • Intermittent Mobile Applications • Cell phone based Medical Records • SmartTrack: Drug Tracking System • ATMosphere: Intermittent Rural ATMs
Cellphone explosion! • 50-80% coverage in many parts of Africa • 100 million subscribers in India, 200 million in China and growing at 20% • Grameen Phone model • Use a SIM and not a cellphone! • Calling rates are still incredibly high in Africa!
Lightweight Mobile Databases • Need for Tele-consultation • Where there is No Doctor? • Health-workers in the field use cell-phones to enter health records • Need a distributed database synchronization/search mechanism which works over SMS-links • Lightweight Cell-phone based medical record system • Example: CD4 History DB for AIDS patients • Constrained Databases (fields+queries) • Semantic Compression of DB records • Records are SMS-updatable • Privacy + Security Challenges
SmartTrack • Two big problems with ARV Therapy Programs • Drug theft and counterfeit drugs • Patient adherence • SmartTrack • Use Cell phones to track flow of drugs • Tag medication bottles with Smart Tags • Patients report consumption using SMS • User Interface Challenges • User Studies + Initial testing in Ghana, South Africa
Cell-phone based Microfinance • Pitfalls of Existing Microfinance Models • High transaction costs • Corruption • The Branchless Banking Model • Use programmable cell-phones to authenticate transactions • Outsource loan recollection to shop-keepers • Provide SIM cards to shopkeepers and loan-takers • Secure repayment receipts using SMS • Benefits: Reduce transaction costs and corruption
ATMosphere • Rural ATMs over mobile SMS • ATMosphere • Offline authentication • Redistribution of balances • Cash availability • Minimal risk of cheating/overdraft • Results from Uganda model • 99% cash availability • Usage costs of 18 cents/user/year • Up to 10% cash availability in offline mode
Questions? Thank you!
Challenges • Prohibitive cost of smartphones • Limited data communication infrastructure • Cost of communication • Language • Illiteracy
Motivation • Maintaining accountability in the supply chain • Tracking patient adherence and symptoms • Cellphones as a healthcare platform
Results • Elimination of intra-path interference leads to multi-hop throughputs comparable with single-hop throughputs • Having multiple gateways greatly improves spatial frequency reuse, leading to high overall throughput • Load and short-time-scale link variance is very important to consider when evaluating a link • Routes and channels are stable, under ROMA