1 / 41

Overcoming Challenges in Network Design: A Contextual Approach

This presentation by S. Keshav at the University of Waterloo discusses the complexities of designing network systems in challenging environments. It emphasizes the necessity of understanding the social, cultural, and economic contexts that influence technology adoption and success. Using the SoftBridge framework, the iterative process of designing, deploying, and refining networks is highlighted, along with guidelines on monitoring, testing, and adapting solutions. Case studies like KioskNet and VLink illustrate practical applications and the importance of iterating on designs to meet real-world requirements.

inge
Télécharger la présentation

Overcoming Challenges in Network Design: A Contextual Approach

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Challenge of Challenged Networks S. Keshav University of Waterloo Dharamshala, September 8, 2010

  2. Waterloo? Where is that?

  3. Home of: RIM/Blackberry Watcom/Sybase Maple OpenText ManuLife

  4. The Challenge of Challenged Networks S. Keshav University of Waterloo Dharamshala, September 8, 2010

  5. A Fundamental Problem • Technology operates in a social, cultural and economic context • Real-world success depends on both the technology and the context • Nearly impossible to determine context in advance • and it may change

  6. Challenged networks • Challenging conditions create unique requirements and also place strong constraints including: • Environmental • Infrastructural • Social • Cultural • Legal • Economic

  7. How to proceed? • Iterative process of design, deployment, and refinement

  8. Context: requirements, constraints, and alternatives Design Redefine requirements and constraints Implement Test Monitor Deploy

  9. Context: the SoftBridge stack People People UI UI Synch Synch Media Media Device Device Network Network Power Power Tucker and Blake, University of the Western Cape, South Africa

  10. Design • Design every layer of the SoftBridge stack, not just the network! • DTN offers alternatives but is not a panacea • Don’t underestimate cellular networks • economies of scale • femtocells

  11. Implement • Challenged networks limit options • avoid lock-in • Don’t build on unproven technology • ‘error 22’ (?) • Build in monitoring

  12. Test • Don’t skimp on testing, painful though it may be • Build test harnesses • Always investigate unexpected results • What you cannot explain is at the heart of new knowledge

  13. Deploy • Always start with a pilot • Feet on the street • Start small

  14. Monitor • Monitor everything • Visualize data graphically • Don’t skimp on analysis • Insist on formal reporting

  15. Refine • Use monitoring data to refine assumptions, constraints, and requirements • Be prepared to throw away the first and second systems • ruthlessness is essential

  16. The rule of three • The first system is too naïve • The second system is too ambitious • The third system is usable

  17. Another rule of three • The first system is too simple • The second system is too complex • The third system is simple in just the right ways Strive to achieve the second simplicity!

  18. Summary so far • Contextualize • Iterate • Simplify

  19. Case study: KioskNet

  20. KioskNet (2005-2008) Trade delay for cost

  21. People UI Synch Media Device Network Power

  22. Experiences • Single-board Linux-based computers are not mass-market • hard to debug and maintain by locals • Vehicular environment is harsh • failure • theft • Difficult to get agreement from transportation providers

  23. VLink (2009) • Addresses problems with KioskNet • Reuses existing Windows and Linux desktops • Software-only solution • No computer in vehicle • No need for buy in from transportation authorities • and MUCH cheaper! • Leverages USB memory sticks (KeyLink) and SMS (SMSLink)

  24. Applications • Email • VSync • keeps two directories in sync

  25. Outcome? • Probably a failure • NGOs do not want unsupported software • SMS/voice communication on mobiles appears adequate • 3G is coming

  26. Case study: TIER/Aravind People UI Synch Media Device Network Power

  27. Conclusions • Designing any successful network is difficult; challenging environments exacerbate this • Contextualize using the SoftBridge stack • Iterate to build at least three solutions • Simplify the system systematically and ruthlessly • Success is not assured

  28. Grad students : S. Liang, A. Seth, N. Ahmed, M. Ghaderi, S. Guo, M.H. Falaki, S. Ur Rahman, E. A. Oliver, U. Ismail, S. Rahbar Graduate interns: R. Luk, Z. Koradia Staff Programmer: D. Kroeker, M. Derakhshani, A. Ganjali Undergrads :  M.Zaharia, P. Darragh,  N. Arora, Y. Yin, G. Salmon, G. Wang, M. Liang, M. Thomas, A. Agarwal,Y. Xu, Y. Hu, S. Dube, R. Sethi, C. Ho,  C. Tan, A. Leong Affiliated Faculty:  T. Brecht (UW), U. Hengartner (UW), S. Prasad  (IIT Delhi), H. Saran (IIT Delhi) Staff support:  G. Chopiak Thank you!

More Related