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 network activity, etc. Eduardo Soria-Vazquez 2
MPC setting in this talk Preprocessing corr. rand. a b Online c d Eduardo Soria-Vazquez 3
Corruption thresholds vs communication complexity of f pra ractical MPC Corruptions: Efficiency: Peter Scholl 4
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? Peter Scholl 5
Our results
In Introducing the Tin inyKeys technique
Warm-up: Distributed Encry ryption 8
Distributed Encry ryption with TinyKeys Eduardo Soria-Vazquez 9
Distributed Encry ryption with TinyKeys 10
Breaking security Eduardo Soria-Vazquez 11
Breaking security Eduardo Soria-Vazquez 12
Breaking security Eduardo Soria-Vazquez 13
Breaking security Eduardo Soria-Vazquez 14
Breaking security Eduardo Soria-Vazquez 15
Breaking security Eduardo Soria-Vazquez 16
Breaking security = y Eduardo Soria-Vazquez 17
Breaking security: Regular Syndrome Decoding y = h blocks e Eduardo Soria-Vazquez 18
Hardness of f Regular Syndrome Decoding [FS09] [Saa07] [MO15] [NCB11] [Kir11] [BM17] [BJMM12] [CJ04] [BLN+09] [BLP08] [MS09] [MMT11] [BLP11] Eduardo Soria-Vazquez 19
TinyKeys: A little honesty goes a l long way (Tiny) GMW (Tiny) BMR OT Eduardo Soria-Vazquez 20
Tiny) GMW (Ti
Quick recap of f GMW P8 P1 P7 P2 P6 1-out-2 Bit OT P3 P5 P4 Eduardo Soria-Vázquez 22
[ I shai K ilian N issim P etrank 03] “IKNP” OT extension with short keys! Shrink the keys! Eduardo Soria-Vazquez 23
Using leaky OT for GMW-style MPC Sharings of zero: Leaky OT Eduardo Soria-Vázquez 24
GMW: Communication compl. (2 (200 parties) 3000 2500 Comm. (bits/AND triple) 2000 Standard [DKSSZZ17] 1500 Committee 1000 TinyKeys 500 0 0 10 20 30 40 50 60 70 80 90 100 # honest parties Eduardo Soria-Vázquez 25
Conclusion and fu future directions Eduardo Soria-Vázquez 26
Thank you! Questions? Paper: 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 Mail: eduardo.soria-vazquez@bristol.ac.uk Eduardo Soria-Vázquez 27
[ B eaver M icali R ogaway 90] BMR: Multi-party garbled circuits Shrink the keys! Eduardo Soria-Vázquez
iny) BMR: Some technical challenges (T (Tin • 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]) Eduardo Soria-Vázquez
Thank you! Questions? Paper: 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 Mail: eduardo.soria-vazquez@bristol.ac.uk Eduardo Soria-Vázquez 31
Recommend
More recommend