### Network Oblivious Transfer

Ranjit Kumaresan, Srinivasan Raghuraman, and Adam Sealfon

##### Abstract

Motivated by the goal of improving the concrete efficiency of secure multiparty computation (MPC), we study the possibility of implementing an infrastructure for MPC. We propose an infrastructure based on oblivious transfer (OT), which would consist of OT channels between some pairs of parties in the network. We devise information-theoretically secure protocols that allow additional pairs of parties to establish secure OT correlations using the help of other parties in the network in the presence of a dishonest majority. Our main technical contribution is an upper bound that matches a lower bound of Harnik, Ishai, and Kushilevitz (Crypto 2007), who studied the number of OT channels necessary and sufficient for MPC. In particular, we characterize which n-party OT graphs G allow t-secure computation of OT correlations between all pairs of parties, showing that this is possible if and only if the complement of G does not contain the complete bipartite graph K_{n-t,n-t} as a subgraph.

Available format(s)
Publication info
A minor revision of an IACR publication in CRYPTO 2016
Keywords
Secure multiparty computationoblivious transferdishonest majorityinfrastructure.
Contact author(s)
asealfon @ mit edu
History
2016-06-11: last of 3 revisions
See all versions
Short URL
https://ia.cr/2016/584

CC BY

BibTeX

@misc{cryptoeprint:2016/584,
author = {Ranjit Kumaresan and Srinivasan Raghuraman and Adam Sealfon},
title = {Network Oblivious Transfer},
howpublished = {Cryptology ePrint Archive, Paper 2016/584},
year = {2016},
note = {\url{https://eprint.iacr.org/2016/584}},
url = {https://eprint.iacr.org/2016/584}
}

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