A Framework for Digital Object Self-Preservation

1
Unsupervised Creation of Small World Networks for
the Preservation of Digital Objects
Charles L. Cartledge Michael L. Nelson Old
Dominion University Department of Computer
Science Norfolk, Virginia
2
Order of Presentation

• Technology enablers
• Constraints
• Simple rules for Complex Behavior
• Simulation approach
• Simulation results
• Future work

3
Motivation
4
Technology Enablers
Cost data http//www.archivebuilders.com/whitepap
ers/22011p.pdf
5
Constraints

6
Reynoldss Rules for Flocking

• Collision Avoidance avoid collisions with nearby
  flock mates
• Velocity Matching attempt to match velocity with
  nearby flock mates
• Flock Centering attempt to stay close to nearby
  flock mates

Images and rules http//www.red3d.com/cwr/boids/
Doctoral Consortium
6
7
Types of Graphs
(Each graph has 20 vertices and 40 edges.)
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Desirable Graph Properties
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Unsupervised Small World Graph Creation

• gamma 0.0
• alpha 0.99

• gamma 0.7
• alpha 0.99

• 0.2 lt beta lt0.66
• gamma lt 0.6

CC is shown as dark lines L is shown as light
lines
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Phases/Activities
11
Creation
Any DO
12
Wandering
A
B
D
C
13
Connecting
A
B
D
C
14
Flocking
A
A
A
A
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Typical Simulation Parameters

• alpha 0.5
• beta 0.6
• gamma 0.1
• Number of DOs 1000
• Number of hosts 1000
• Min number desired replicas 3
• Max number desired replicas 10
• Max number of replicas per host 20

16
Simulation Results and Analysis
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Future work

• Test the autonomous graphs for resilience to
  error and attack
• Test what happens when a graph becomes
  disconnected
• Test what happens when a disconnected graph
  becomes re-connected

18
Conclusions

• We have shown that Digital Objects can
  autonomously create small world graphs based on
  locally gleaned data
• These graphs can be used for long term
  preservation
• We intend to study these graphs focusing on their
  tolerance to isolated and widespread failures

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And that concludes my presentation.
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Backup Information

• Equations for Average Path Length and Clustering
  Coefficients