As an application, we show a very efficient reductions in the malicious model of RabinOT over strings to one-out-of-two oblivious transfer over bits (OT) that is only secure in the semi-honest model. For string of size $\ell = \omega(k^2)$, our reductions uses only $4 \ell + o(\ell)$ instances of OT, while previous results required $\Omega(\ell k^2)$. Our new reduction leads to an efficiency improvement for general multi-party computation (MPC) based on semi-honest OT, and makes it almost as efficient as MPC based on malicious OT.
All reductions are unconditionally secure, black-box, universally composable and secure against adaptive adversaries.
Category / Keywords: cryptographic protocols / oblivious transfer, multi-party computation, black-box reductions, combiners, universal composability Date: received 2 Sep 2009 Contact author: j wullschleger at bristol ac uk Available format(s): PDF | BibTeX Citation Version: 20090904:054219 (All versions of this report) Short URL: ia.cr/2009/428