Taming Adaptivity in YOSO Protocols: The Modular Way

Ran Canetti*, Sebastian Kolby, Divya Ravi, Eduardo Soria-Vazquez, Sophia Yakoubov

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

YOSO-style MPC protocols (Gentry et al., Crypto’21), are a promising framework where the overall computation is partitioned into small, short-lived pieces, delegated to subsets of one-time stateless parties. Such protocols enable gaining from the security benefits provided by using a large community of participants where “mass corruption” of a large fraction of participants is considered unlikely, while keeping the computational and communication costs manageable. However, fully realizing and analyzing YOSO-style protocols has proven to be challenging: While different components have been defined and realized in various works, there is a dearth of protocols that have reasonable efficiency and enjoy full end to end security against adaptive adversaries. The YOSO model separates the protocol design, specifying the short-lived responsibilities, from the mechanisms assigning these responsibilities to machines participating in the computation. These protocol designs must then be translated to run directly on the machines, while preserving security guarantees. We provide a versatile and modular framework for analyzing the security of YOSO-style protocols, and show how to use it to compile any protocol design that is secure against static corruptions of t out of c parties, into protocols that withstand adaptive corruption of T out of N machines (where T/N is closely related to t/c, specifically when t/ c< 0.5, we tolerate T/ N≤ 0.29 ) at overall communication cost that is comparable to that of the traditional protocol even when c< < N. Furthermore, we demonstrate how to minimize the use of costly non-committing encryption, thereby keeping the computational and communication overhead manageable even in practical terms, while still providing end to end security analysis. Combined with existing approaches for transforming stateful protocols into stateless ones while preserving static security (e.g. Gentry et al. 21, Kolby et al. 22), we obtain end to end security.

Original languageEnglish
Title of host publicationTheory of Cryptography - 21st International Conference, TCC 2023, Proceedings
EditorsGuy Rothblum, Hoeteck Wee
PublisherSpringer Science and Business Media Deutschland GmbH
Pages33-62
Number of pages30
ISBN (Print)9783031486173
DOIs
StatePublished - 2023
Externally publishedYes
Event21st International conference on Theory of Cryptography Conference, TCC 2023 - Taipei, Taiwan, Province of China
Duration: 29 Nov 20232 Dec 2023

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume14370 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349

Conference

Conference21st International conference on Theory of Cryptography Conference, TCC 2023
Country/TerritoryTaiwan, Province of China
CityTaipei
Period29/11/232/12/23

Funding

FundersFunder number
Digital Research Centre Denmark
European Unions’s Horizon 2020 research and innovation programme803096
European Research Council
Danmarks Frie ForskningsfondDFF-2064-00016B

    Fingerprint

    Dive into the research topics of 'Taming Adaptivity in YOSO Protocols: The Modular Way'. Together they form a unique fingerprint.

    Cite this