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Carmit Hazay, Emmanuela Orsini, Peter Scholl and Eduardo Soria-Vazquez
Motivation
Large number of users want to conduct surveys, auctions, statistical analysis, measure network activity, etc.
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A new approach to efficient multi-party computation Carmit Hazay, - - PowerPoint PPT Presentation
A new approach to efficient multi-party computation Carmit Hazay, - - PowerPoint PPT Presentation
Tin inyKeys: : A new approach to efficient multi-party computation Carmit Hazay, Emmanuela Orsini, Peter Scholl and Eduardo Soria-Vazquez Motivation Large number of users want to conduct surveys, auctions, statistical analysis, measure
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MPC setting in this talk
Preprocessing Online a b c d
corr. rand.
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Peter Scholl 4
Corruption thresholds vs communication complexity of f pra ractical MPC
Corruptions: Efficiency:
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Peter Scholl 5
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Corruption thresholds vs communication complexity of f practical MPC
Corruptions: Efficiency:
Can we design concretely efficient MPC protocols where each honest party can be leveraged to increase efficiency?
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Our results
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In Introducing the Tin inyKeys technique
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Warm-up: Distributed Encry ryption
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Distributed Encry ryption with TinyKeys
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Distributed Encry ryption with TinyKeys
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Breaking security
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Breaking security
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Breaking security
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Breaking security
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Breaking security
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Breaking security
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Breaking security
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y =
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e
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Breaking security: Regular Syndrome Decoding
y =
h blocks
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Hardness of f Regular Syndrome Decoding
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[Saa07] [BM17] [MO15] [NCB11] [BLN+09] [Kir11] [CJ04] [FS09] [MMT11] [BJMM12] [BLP08] [BLP11] [MS09]
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TinyKeys: A little honesty goes a l long way
(Tiny)GMW (Tiny)BMR
OT
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(Ti Tiny)GMW
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P7
P8
P6 P5 P4 P3 P1 P2
Quick recap of f GMW
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1-out-2 Bit OT
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“IKNP” OT extension
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[Ishai Kilian Nissim Petrank 03] Shrink the keys!
with short keys!
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Sharings
- f zero:
Using leaky OT for GMW-style MPC
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Leaky OT
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GMW: Communication compl. (2 (200 parties)
25 500 1000 1500 2000 2500 3000 10 20 30 40 50 60 70 80 90 100
- Comm. (bits/AND triple)
# honest parties
Standard [DKSSZZ17] Committee TinyKeys Eduardo Soria-Vázquez
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Conclusion and fu future directions
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Thank you! Questions?
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https://ia.cr/2017/214 [Full version] TinyKeys: A New Approach to Efficient Multi-Party Computation Carmit Hazay, Emmanuela Orsini, Peter Scholl and Eduardo Soria-Vázquez eduardo.soria-vazquez@bristol.ac.uk Paper: Mail:
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BMR: Multi-party garbled circuits
Shrink the keys! [Beaver Micali Rogaway 90]
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(T (Tin iny)BMR: Some technical challenges
- Reusing keys reduces security in regular syndrome decoding
- Problem for:
- High fan-out
- Free-XOR
- Solution:
- Splitter gates [Tate Xu 03] – can be garbled for free
- Free-XOR enabled using different offsets (FleXOR style [CITE])
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Thank you! Questions?
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https://ia.cr/2017/214 [Full version] TinyKeys: A New Approach to Efficient Multi-Party Computation Carmit Hazay, Emmanuela Orsini, Peter Scholl and Eduardo Soria-Vázquez eduardo.soria-vazquez@bristol.ac.uk Paper: Mail: