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A Biologically Inspired Programming Model
for Self-Healing Systems
Selvin GeorgeComputer Science
David EvansComputer Science
Lance DavidsonBiology
U N I V E R S I T Y O F V I R G I N I A
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Self Healing in Nature
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Diffusion – Local Communication
Cells are aware of surroundings by sensing chemicals emitted by other cells
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Nature’s Programs – Observations
• Aware• Of self• Of environment
• Redundant• Decentralized• Expressive
• Human program – 3 billion base pairs (~250MB)
• Two human programs differ by about 0.5MB (< 1% of Windows 2000)
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Our Programming Model
• Similar to cellular automata• Simple chemical diffusion model• Correspondence to biological cells
– Genes turn on and off state changes•Emit different chemicals depending on
state•Change state based on sensed chemicals
– Cells can divide asymmetrically
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state s1 { emits (a, 0.1) transitions (0 <= a <= 0.375) -> (s2, s2) axis; -> (s1);}
state s2 { emits (a, 0.1) transitions (0 <= a <= 0.375) -> (s3, s3) normal-X; -> (s2);}
state s3 { emits (a, 0.1) transitions (0 <= a <= 0.375) -> (s1, s1) normal-Y; -> (s3);}
Blastula Progra
ms1
s2
s3
a
a
a
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Self-Healing Blastulastate s1 { emits (a, 0.1) transitions (0 <= a <= 0.375) -> (s2, s2) axis; -> (s1);}
state s2 { emits (a, 0.1) transitions (0 <= a <= 0.375) -> (s3, s3) normal-X; -> (s2);}
state s3 { emits (a, 0.1) transitions (0 <= a <= 0.375) -> (s1, s1) normal-Y; -> (s3);}
Kill Cell
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Distributed Wireless File Service
File Distribution and Update
Server
replicate
inhibit
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Distributed Wireless File Service
File Distribution and Update
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Purple Nodes – store File 1
Concentric Circles– Inhibit/Replicate
Green Circle– File Request
White Circle– Server Response
DWFSSimulatio
n
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Mantra
• Biology has killed trillions of organisms over millions of years to solve complex engineering problems
• Engineers should be able to learn from these solutions
• Simulator available: http://swarm.cs.virginia.edu/cellsim