Simple direct reduction of string (1,2)-OT to Rabin's OT without privacy amplification

Abstract

It is known that string (1,2)-OT and Rabin's OT are equivalent. Actually, there have been many reductions between them. Many of them use the privacy amplification technique as a basic tool. The privacy amplification technique essentially involves some post-processing of sending random objects (e.g., random indices of pairwise independent hash functions) per each invocation of Rabin's OT is necessary. In this paper, we show a simple direct reduction of string (1,2)-OT to Rabin's OT by using a deterministic randomness extractor for bit-fixing sources. Our reduction can be realized without privacy amplification and thus our protocol is simpler and more efficient with respect to the communication complexity than the previous reductions. © 2008 Springer-Verlag Berlin Heidelberg.