Low-Cost Internet Access Using KioskNet Earl Oliver PhD Student Tetherless Computing Research Group University of Waterloo (Canada) With: S. Guo, H. Falaki, S. Ur Rahman, A. Seth, M. Zaharia, U. Ismail, and Prof. S. Keshav Key points • Robust, reliable, and low-cost network connectivity for rural regions • Supports incremental deployment by franchisees (secure) • Secure communication between users and the Internet • Supports future network availability (ex. WiMAX, cellular, etc.) • Available today, free for download Why low cost networking? • Access to timely, context-specific information can greatly benefit citizens of developing countries • Farmers – Best agricultural practices – Crop inputs and treatments – Market prices • Health workers – Diagnosis – Treatment • Citizens – Government services – Communication (email) Example • aAqua project (IIT Bombay, Maharastra, India) – Bulletin board system allows farmers to consult with agricultural experts • market opportunities • fertilizers • pricing • Sample questions: – How much money can you make from a Jersey cow worth Rs. 20,000 in a year? – I want information of producing and implementation of Jatropha plant for Bio-Diesel. – We have at our disposal 10-12tonnes of aloe vera plants/leaves for sale. Parties interested in purchasing please catch us at 09864031770 Low cost communication and access to information… • Allows better decision making • Improves worker productivity • Integrates economies into the world market • Prevents `leakage’ of development funds • Promotes an informed citizenry and a participatory democracy How to provide low-cost access to information? Information access today • Mostly one-way – Radio – TV – Newpapers – Magazines • These solutions are inadequate Two way information flow • Possible using newer technologies – Cell phones – Internet • But can be expensive – Rural poor are unlikely to get good connectivity any time soon – Revenue per sq. km << cost per sq. km • Can we provide reliable connectivity for only a few dollars / person / year? How to reduce costs? • Sharing the cost of the technology • Sharing the cost of knowing how to use the technology • Information kiosk Kiosk connectivity • Dial-up – Slow (28 kbps) and flaky • Satellite (Very Small Aperture Terminals) – Expensive and slow – Spare parts are hard to get • Long range WiFi / WiMax – Experimental – Expensive up-front cost (for 18m tower) • Cellular broadband (3G) – Low penetration because of high upfront costs Mechanical backhaul Kiosk The Kiosk controller • Headless, keyboardless, low-cost, lowpower single board computer. • Powered by solar power + battery – (near full uptime) • Supports wide range of network interfaces – Choice of interface is policy driven at the session layer Kiosk controller cont’d • Two access modes: – Terminal: recycled PCs netboot from a read-only image stored on the kiosk controller. – Direct: access the controller (or bus or gateway) like a WiFi hotspot. Ferry Gateway Ferries and gateways • No processing of data – only store and forward – Without power restrictions – Recommended to have faster CPU, higher memory than kiosk controller • Gateway has an always-on connection to the Internet (proxy) Proxy • Centralized server on the Internet • Disconnection-aware • Hides disconnected users from legacy servers • Plug-in applications – Ex. SMPT plug-in to handle email service • DNS location register • Public key database (whitepages directory) Advantages of mechanical backhaul • Low cost of connectivity per kiosk (< $250 capital expenditure) – Cost of the ferry and gateway single board computer gets shared across kiosks – $3/person/year to break even at 10% penetration • no trench, no tower ! • See paper for calculations and cost breakdown. • Increased penetration – Even in interior areas where there are no telephone lines • High bandwidth data transfer in both directions • Rapidly and incrementally deployable Disadvantages • Data transfer is delayed – Depends on frequency of visits of vehicles – Can be several days • But many useful applications are delay tolerant – Trade delay for cost • Suitable for smaller non-governmental organizations to set up kiosks Low cost connectivity • What are the challenges? – – – – – Supporting multiple network interfaces Security Routing User management Maintenance and redundancy (debugging system failure) Supporting multiple NICs • Need to support new networks • Mechanical backhaul not ideal for all applications – Ex. High priority data • Opportunistic Connection Management Protocol (OCMP) – Applies application specific policies to schedule data across multiple NICs – Currently mechanical backhaul, SMS, and TCP/IP supported. Security • Resilient to a diverse set of internal and external attacks • PKI rooted at University of Waterloo – sub-CAs operated by KioskNet franchisers and franchisees – X.509 public keys flooded to kiosks to provide secure communication between users • Encrypted user file system – Keyed by user password, NFS mounted at logon • Kiosk netboots from read-only image stored on the kiosk controller Routing • Many DTN routing options – Robustness vs. efficiency – Guaranteeing reliability is hard • Flood within a ‘region’ – Hierarchical namespace: <kiosk>.<region>.<provider>.kiosknet.org • Upstream: gateways coordinate to send one copy of data to proxy • Downstream: data sent to one region’s gateway – DNS query based on user EID to determine gateway User management • Distribute user creation to kiosks – Walk in, get an account • Extended system admin application: webmin to create/delete users and public keys • Keys are signed by the local franchisee and sent to the proxy with the user’s EID – <user>.<kiosk>.<region><org>.kiosknet.org • EIDs and certificates flooded back to all kiosks Maintenance and redundancy • Applying software updates/bug fixes can be expensive • Robust mechanism for pushing updates (debian packages) • Remote shell for remotely executing bash scripts • Software failures can occur in the field – Need a mechanism to collect debugging information • rsync/ssh flooding of logs – Activated by inserting a special USB key or via remote shell Sample applications • Email – Classic application for delay tolerant networks – user@<kiosk>.<region>.<org>.kiosknet.org • Database synchronization – Replicate a centralized database to kiosks – Ex. aAqua (IIT Bombay) • YouTube – Download videos to kiosk based on a search query • Flickr – Take a picture, upload it to Flickr Current status • Live deployment in Anandpuram, India • Second deployment mid December (IIT Delhi) • Preparing second major release for early 2008 that includes security, SMS, and DNS user lookups Future work • Support for mobile users – Routing, security, user management – Recycled cell/smart phones • Robustness – Exploit the cellular network as a control channel • Applications, applications, applications – “if you build it they will come” might not apply Conclusions • Developed a secure, robust system to provide low-cost Internet to rural regions • KioskNet can adapt to the availability to new networks • KioskNet is free and rapidly deployable For more information • Earl Oliver, eaoliver@uwaterloo.ca • Prof. Keshav, keshav@uwaterloo.ca • Web: http://blizzard.cs.uwaterloo.ca/tetherless/ • Join our mailing list