Cryptology ePrint Archive: Report 2016/584

Network Oblivious Transfer

Ranjit Kumaresan and 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.

Category / Keywords: Secure multiparty computation, oblivious transfer, dishonest majority, infrastructure.

Original Publication (with minor differences): IACR-CRYPTO-2016

Date: received 3 Jun 2016, last revised 10 Jun 2016

Contact author: asealfon at mit edu

Available format(s): PDF | BibTeX Citation

Version: 20160611:054822 (All versions of this report)

Short URL:

[ Cryptology ePrint archive ]