Your SlideShare is downloading. ×
Opportunistic composition of sequentially-connected services in mobile computing environments
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Opportunistic composition of sequentially-connected services in mobile computing environments

709
views

Published on

Presentation at the International Conference for Web Services 2011. Presented with Best Student Paper Award. …

Presentation at the International Conference for Web Services 2011. Presented with Best Student Paper Award.

Imagine using mobile device capabilities and participatory sensing to create new value-added services from existing device services

Published in: Technology, Business

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
709
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
2
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Opportunistic composition of sequentially-connected services in mobile computing environments Christin Groba and Siobhán Clarke – Trinity College Dublin IEEE International Conference of Web Services Washington D.C., 5th July 2011Lero© 2011
  • 2. Mobile environments are the new frontier for service providersLero© 2011 2
  • 3. Getting to the airportLero© 2011 3
  • 4. Fastest routeLero© 2011 4
  • 5. DisruptionLero© 2011 5
  • 6. What is the fastest alternative ?Lero© 2011 6
  • 7. What is the fastest alternative ? Browsing the Web Walk 5 min Walk 3 min Bus in 6 min Reality Walk 5 minLero© 2011 7
  • 8. How to obtain real-time data? GPS Accel Navi Camera Utilise mobile device capabilities & participatory sensingLero© 2011 8
  • 9. Real-time data as decision support Real-time data Walk 5 min Real-time data Walk 5 minLero© 2011 9
  • 10. Mobility and resource scarcity make service composition challengingLero© 2011 10
  • 11. Challenge: Dynamic setting No central control High failure probabilityLero© 2011 11
  • 12. Challenge: Energy scarcity Wireless communication drains batteryLero© 2011 12
  • 13. Emergence of dynamic ad hoc environments has led to decentralised composition algorithmsLero© 2011 13
  • 14. Decentralised composition BindingLero© 2011 14
  • 15. Decentralised composition BindingLero© 2011 15
  • 16. Decentralised composition BindingLero© 2011 16
  • 17. Decentralised composition BindingLero© 2011 17
  • 18. Decentralised composition BindingLero© 2011 18
  • 19. Decentralised composition BindingLero© 2011 19
  • 20. Decentralised composition Binding Once all service are bound, execution can startLero© 2011 20
  • 21. Decentralised composition Execution Binding Once all service are bound, execution can startLero© 2011 21
  • 22. Decentralised composition Execution Binding Once all service are bound, execution can startLero© 2011 22
  • 23. Decentralised composition Execution Binding Once all service are bound, execution can startLero© 2011 23
  • 24. Decentralised composition Execution Binding Once all service are bound, execution can startLero© 2011 24
  • 25. Decentralised composition Execution Binding Once all service are bound, execution can startLero© 2011 25
  • 26. Decentralised composition Execution Binding Once all service are bound, execution can startLero© 2011 26
  • 27. Many decentralised composition approaches bind providers too earlyLero© 2011 27
  • 28. Bound but not usedLero© 2011 28
  • 29. Disconnect Recovery Communication EnergyLero© 2011 29
  • 30. How to reduce failure probability?Lero© 2011 30
  • 31. Reduce the delay between service binding and service executionLero© 2011 31
  • 32. Opportunistic execution model BindingLero© 2011 32
  • 33. Opportunistic execution model Execution Binding Execute service while searching for the next providerLero© 2011 33
  • 34. Opportunistic execution model Execution Binding Execute service while searching for the next providerLero© 2011 34
  • 35. Opportunistic execution model Execution Binding Execute service while searching for the next providerLero© 2011 35
  • 36. Opportunistic execution model Execution Binding No unnecessary binding of conditional pathsLero© 2011 36
  • 37. Opportunistic execution model Execution BindingLero© 2011 37
  • 38. Opportunistic execution model Execution Binding Bind available providerLero© 2011 38
  • 39. Opportunistic execution model Execution Binding Provider likely to be still available if execution follows immediately after bindingLero© 2011 39
  • 40. Opportunistic execution model Execution BindingLero© 2011 40
  • 41. System model Abstract composite request < composite > := seq(< composite >;< composite >) |< type > | < type >:< provider > < type > := S1 |…| Sn < provider > := P1 |…| Pm Directory-less, on demand discovery Proximity-based selectionLero© 2011 41
  • 42. Evaluation Simulation Jist/SWANS Ulm Random Waypoint Controlled Composition length Node speed Metric Success ratio Response time Communication effortLero© 2011 42
  • 43. Do composites execute to completion? Opportunistic model 28% more successful Node speed: 1-13 m/s 80 60 Success ratio(%) 40 baseline opportunistic 20 0 4 5 6 7 Composition lengthLero© 2011 43
  • 44. Do composites respond to initiator quicker? Opportunistic model 33% faster Node speed: 1-13 m/s 8 Response time (s) 6 baseline 4 opportunistic 2 0 4 5 6 7 Composition lengthLero© 2011 44
  • 45. Do composites communicate unnecessarily? Opportunistic model 14% less chatty Node speed: 1-13 m/s 120 Number of sent messages 100 80 60 baseline opportunistic 40 20 0 4 5 6 7 Composition lengthLero© 2011 45
  • 46. Current & Future work Service flows Service requests contain splitting and merging paths Failure recovery Composition success cannot be guaranteed and recovery strategies are essential Privacy Participants aware of control and data flow which may include sensitive information Device heterogeneity Resource-poor devices require light-weight integration conceptLero© 2011 46
  • 47. Recap New frontier Share mobile device capabilities and create new value-added service composites Challenge How to reduce the failure probability of service composites? Approach Reduce delay between binding and execution Results More successful, faster, and less chatty than “first bind all then execute” approach Current work Service flows and failure recovery Future work Privacy and device heterogeneityLero© 2011 47
  • 48. Thank you!Lero© 2011

×