How small labels create big improvements

1
How small labels create big improvements

• Pan Hui
• Jon Crowcroft
• Computer Laboratory
• University of Cambridge

2
US-based Conferences

• In Memory of
• 9/11/01
• We will never FORGET
• It IS Terrorists make USA government delaying
  visas for Asian people.

3
Outlines

• Community and forwarding in PSN
• Affiliations-based iMote Experiment
• LABEL a community based forwarding
• Empirical results of community improves
  forwarding
• Conclusion

4
Community and Forwarding

• PSN human mobile networks under DTN and MANET
• Naive forwarding schemes created unwanted
  traffics
• Identifying community information improve
  forwarding efficiency
• No empirical evaluation of this belief

5
Affiliations based iMotes Experiment

• Infocom 2006 Barcelona, Spain (not USA)
• 4 affiliation groups of 34 people
• 2 Paris groups, 1 Switzerland group, 1 Barcelona
  group
• Largest group of 15 people
• Carry the iMotes during the conference period
• iMotes log the contact with each otherother
  Bluetooth devices

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Label Strategy (LABEL)

• Priori label, e.g. affiliation
• Correlated interaction
• Forward to nodes have same label as the
  destination
• Good performance in conference mixing environment

Destination GOOD PEOPLE
USA soldiers
Asian people
LABEL GOOD PEOPLE
LABEL BAD PEOPLE
Pretty Ladies
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Empirical Results
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Problem with LABEL

• In a less mixing environment
• A person in one group may not meet members in
  another group so often
• Wait for destination group not efficient
• So smarter strategies make use of community
  information should be investigated

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Conclusions

• Even very small amount of state information bring
  significant improvement in forwarding efficiency
• Need to embed state information in future design

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• Thank you !
• http//www.cl.cam.ac.uk/ph315/
• Pan.Hui_at_cl.cam.ac.uk
• Jon.Crowcroft_at_cl.cam.ac.uk