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Melissa R. Ho School of Information RJ Honicky EECS University of California, Berkeley

Reassessing Long Distance Wireless for West Africa. Melissa R. Ho School of Information RJ Honicky EECS University of California, Berkeley. Wireless Broadband Access for Communities and Rural Developing Regions (WIRELESS4D’08) Karlstad University, Sweden 11-12 December 2008.

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Melissa R. Ho School of Information RJ Honicky EECS University of California, Berkeley

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  1. Reassessing Long Distance Wireless for West Africa Melissa R. Ho School of InformationRJ HonickyEECSUniversity of California, Berkeley Wireless Broadband Access for Communities and Rural Developing Regions (WIRELESS4D’08) Karlstad University, Sweden 11-12 December 2008

  2. Long Distance WiFi long 10-150km cheap $1000 free spectrum fast up to 20Mbps wireless links + = slide from S. Nedevschi, TIER Workshop 2008

  3. Wi-Fi Long Distance (WiLD) slide from S. Nedevschi, TIER Workshop 2008

  4. El Alguila to Platillon – 382 km 6 Mbps with WiLDNet

  5. Aravind Theni Telemedicine Network

  6. Real Impact

  7. Guinea-Bissau Ghana But what happens in other contexts? Two cases in West Africa: a community radio network in Guinea Bissau, and a inter-university library network and hospital telemedicine network in Ghana

  8. Guinea Bissau: Community Radio Syndication Network Collaboration with US-AID and Eguitel Networking 15 community radio stations DTN/TierStore overlay enabling content sharing of recorded broadcasts over intermittent network Wireless network utilizes existing radio station infrastructure: power, mast, and technical expertise

  9. Guinea Bissau Software Architecture

  10. The Guinea Bissau Network

  11. Ghana Wireless Inter-University Network Dedicated wide area network (WAN) Inter-library communication for card catalog sharing and electronic library resources Use of local partner for installation an training Network maintained by university students and network administration staff Complementing existing GARNET project

  12. Ghana Inter-University Wireless Deployment 20m 20m 9.2 km 80m 12.9 km 18.2 km 70 km 60 km 60 km

  13. Low-cost equipment alone could not catalyze rural wireless broadband in these contexts • High transportation costs • Increased labor costs • Increased infrastructure costs • Poor power infrastructure • Local policies: spectrum, customs/import • Highly regulated/monopolized telecommunications sectors

  14. In Africa • Concentrated in urban areas • Mostly Monopolies • SAT3/WASC/SAFE submarine fiber to Portugal • Exclusive rights initially granted to select investors • Access is generally overpriced • Largely served by VSAT • AfrISPA has established Internet Exchanges in 13 countries Image taken from “Fiber-optic Cable Wires Africa.” Red Herring. Nov. 11, 2005 Image taken from Network Startup Resource Center (http://nsrc.org/AFRICA/afr_ix.html) Feb 27, 2007

  15. Ghana Remote Relay Station Costs • Towers are a bulk of the cost for wireless deployments • $200/m up to 30 meters • $300/m over 30 meters • 150m tower can cost over $100,000 • Annual Maintenance: $1000 • In Ghana, material availability is a problem, and towers degrade after a few years • Spectrum Licensing • 2.4 Ghz registration $500/yr • 5.x Ghz license $5000/yr/channel/site • Field Engineering • Hotel: $50/night/engineer • Daily rate: $110/day/engineer • Transportation: • Petrol: $.50/mile • Vehicle: $.50/mile • Total: $50-$500 per trip (aka roll)

  16. Technical Challenges • Roadblock #1: Load shedding • Roadblock #2: Equipment-less • Roadblock #3: Tower-less • Pricing Installation • Commissioned vs. Dedicated Staff

  17. Administrative Challenges • Rational and affordable spectrum policy • In Ghana 2.4 is oversubscribed in urban areas • Eguitel has a completely open license – immediate short term gain, but possible long term implications • Maintenance of an inherently unstable network • Compounded by collaboration between several different university units

  18. Addressing the Challenges Often the best solution is to reduce the length of the links and the required height of the mast by introducing intermediate relay points In these cases intermediate relay points were not available kapok trees as pre-existing mast structures electrically steerable antennas lightweight, passively cooled equipment low power solar/wind powered equipment prioritize reliability and robustness to failure rather than “low cost” remote monitoring of power systems (e.g. battery health) for preventative maintenance design for asynchrony to reduce the cost of the system enable trained engineers to work more efficiently or deploy equipment that can be maintained by less-trained staff

  19. Melissa R. Homho@ischool.berkeley.eduhttp://www.melissaho.com Technology and Infrastructure for Emerging Regions (TIER) http://tier.cs.berkeley.edu

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