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Communicating in Wales: design and architecture for mobile applications over poor connectivity

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Keynote at Internet Technologies & Applications (ITA17), Wrexham, North Wales, UK, 14th Sept 2017

This talk presented ways to design both the user experience and the underlying application, data and networking infrastructure to cope with poor or intermittent connectivity.

http://alandix.com/academic/papers/ITA-communicating-in-wales-2017/

Published in: Technology
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Communicating in Wales: design and architecture for mobile applications over poor connectivity

  1. 1. Communicating in Wales: design and architecture for mobile applications over poor connectivity Alan Dix http://alanwalks.wales/
  2. 2. Tiree Tiree Tech Wave 26-30 Oct 2017 University of Birmingham
  3. 3. today I am not talking about … • physicality and product design • long tail of small data • community technology • intelligent internet interfaces • digital humanities • creativity and Bad Ideas • visualisation and sampling • situated displays • virtual crackers and slow time • modelling dreams and regret • the emergence of self
  4. 4. not to mention … REF
  5. 5. I am talking about … connectivity … or the lack of it!
  6. 6. poor connectivity three aspects: • user experience • architecture and infrastructure • policy … but first a little about a walk
  7. 7. walking Wales 1058 miles (1700 km) around around the margins of Wales
  8. 8. Welsh Coast Path opened May 2012 linking existing paths a single way marked route with Offa’s Dyke encircles Wales three full traversals in 2012 (one running)
  9. 9. vision personal encircling, encompassing, pilgrimage, homecoming, practical IT for the walker & IT for local communities philosophical reflections on walking and space, locality and identity research personal agenda and living lab
  10. 10. no hard boundaries research – practice personal – philosophical 19th century science or Mediaeval?
  11. 11. walking Wales technology me: “what technology do you use?” walker: “a map”
  12. 12. the best technology! voice recorder real buttons!! use it while moving
  13. 13. while walking active camera, recorder passive GPS, ECG, EDA when stopped iPad, blog, flickr, social media, uploading data before/after web for planning new contacts on Twitter, email reporting, analysis while walking other walkers occasional friends/family meeting when stopped shop keepers, B&B proprietors, chance meetings talks, visits before/after family and friends, readers, researchers, future walkers social sphere technical sphere
  14. 14. data location GPX ... batteries ... sporadic signals .... bio-sensing ECG (heart), EDA (skin) and accelerometers audio and images in the moment text after the event implicit explicit
  15. 15. user experience connectivity problems I expected it to be bad ... but it was worse
  16. 16. ... not a recent issue ...
  17. 17. not just jerky movies ... Software Update 2.3Gb security patch
  18. 18. software makes it worse ... Twitter 140 chars ... but unusable with poor signal email slow but works – 1970s technology Flickr uploader freezes on poor connections ... even in Paris! ✔ ✗ ✗
  19. 19. user experience principles time matters
  20. 20. timescales ms secs mins hours days local interaction + syncronisation store & forward hand-eye coordination split-feedback syntactic/semantic local feedback pre-compute request response session
  21. 21. vocabulary … just words? bandwidth … how much delay … how long jitter … how variable
  22. 22. glitches frequency length of drop ms secs mins hours days ms secs mins hours days total failure jitter intermittent connectivity glitches
  23. 23. principles store and forward … in an age of instant restarting after problems connectivity-aware applications also cost, energy, etc. e.g. rich media
  24. 24. architecture & infrastructure the bits leak out
  25. 25. recall … software makes it worse ... Twitter 140 chars ... but unusable with poor signal Flickr uploader freezes on poor connections ... even in Paris! N.B. both as in 2013
  26. 26. Twitter experience
  27. 27. Twitter – why? code (on start) – read news-stream – build UI – allow tweets
  28. 28. https://dev.twitter.com/rest/reference/get/statuses/home_timeline
  29. 29. https://dev.twitter.com/rest/reference/get/statuses/home_timeline
  30. 30. 5 pages later … $ wc one-tweet.json 163 304 4468 https://dev.twitter.com/rest/reference/get/statuses/home_timeline
  31. 31. Twitter – why? code (on start) – read news-stream – build UI – allow tweets could be – asynchronous load – lightweight version of API 140 chars = 5-10K in JSON/XML API 50 items (server performance) 50 x 5-10 K = 0.25–0.5 Mbyte … on 2 bars of GSM!
  32. 32. Flickr experience on desktop: – select required files – categorise and tag on send – starts to work – failure – some files uploaded, but untagged – no ability to restart
  33. 33. Flickr– why? code (on send) – upload all images – tag all images could be – build to-do list – for each item in to-do list • upload and tag – on restart: pick up last to-do-list … on fail exit but save to-do list on fail exit
  34. 34. software architecture asynchronous interactions distributed system not thin client – synchronisation technology – inc. partial sync. think local connectivity – – e.g. Qraqrbox (cf. www paper) think failure / restart – e.g. to-do list based coding
  35. 35. protocols IP slow start – resilient to nuclear war … but not Tiree or Wales coast DNS failure caching why glitches??? router overload ?
  36. 36. policy the net privilege of the rich or service for all
  37. 37. always connected? mobile signal absent or weak broadband ... not so broad masts point to sea not land ... yachts = money https://explore.ee.co.uk/coverage-checker
  38. 38. infrastructure or privilege? what is the greatest British invention?
  39. 39. infrastructure or privilege? 19th century – Penny Post the amazing invention revolutionised communication Today – Internet 2013 – 50% of Welsh schools said poor connectivity hampers education 2017 – 7 out of 20 worst connected areas in UK … … in Wales http://www.victorianweb.org/history/pennypos.html
  40. 40. nudge, nudge mobile mast charging – similar to European roaming – change cost-benefit for companies – allow more community masts ISPs & local communities – Tiree local traffic goes to London and back!
  41. 41. glitches? no official word for it! => not in agreements not in contracts not noticed … … unless you have to live with it
  42. 42. in summary user experience – on-going issue – impact for individuals, business and education policy – root cause – privilege or public service? – vocabulary matters architecture – good design ameliorates poor infrastructure

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