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28 lines
1.1 KiB
Plaintext
28 lines
1.1 KiB
Plaintext
The lossmodel.lyx file is the source document for an in-progress paper
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that analyzes the probability of losing files stored in a Tahoe-LAFS
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file store under various scenarios. It describes:
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1. How to estimate peer reliabilities, based on peer MTBF failure
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data.
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2. How to compute file loss probabilities, based on a given set of
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shares stored on peers with estimated reliabilities. The peer
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reliabilities do not have to be uniform, and the model takes into
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account the file repair process.
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3. How to estimate Tahoe parameters for k (shares needed), n (shares
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distributed) and A (repair interval) to achieve a file reliability
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target.
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4. How to compute the estimated repair cost over time, discounted at
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a fixed rate, of maintaining a file for a time period T.
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Future work will also address the latter three issues in the context
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of "non-aggressive" repair, where repair will only be performed if
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too many shares are lost, and it will also extend the repair cost
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estimation model to suggest cost functions appropriate for common
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network architectures.
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A PDF of the current version of the file may be downloaded from:
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http://willden.org/~shawn/lossmodel.pdf |