Oblivious transfer from any non-trivial elastic noisy channel via secret key agreement

Abstract

A (γ, δ)-elastic channel is a binary symmetric channel between a sender and a receiver where the error rate of an honest receiver is δ while the error rate of a dishonest receiver lies within the interval [γ, δ]. In this paper, we show that from any non-trivial elastic channel (i.e., 0 < γ < δ < ½) we can implement oblivious transfer with information-theoretic security. This was previously (Khurana et al., Eurocrypt 2016) only known for a subset of these parameters. Our technique relies on a new way to exploit protocols for information-theoretic key agreement from noisy channels. We also show that informationtheoretically secure commitments where the receiver commits follow from any non-trivial elastic channel.