Oblivious Transfer from Any Non-trivial Elastic Noisy Channel via Secret Key Agreement

Abstract

A $$\gamma ,\delta $$ γ,i¾?-elastic channel is a binary symmetric channel between a sender and a receiver where the error rate of an honest receiver is $$\delta $$ i¾? while the error rate of a dishonest receiver lies within the interval $$[\gamma , \delta ]$$ [γ,i¾?]. In this paper, we show that from any non-trivial elastic channel i.e., $$0<\gamma<\delta <\frac{1}{2}$$ 0<γ<i¾?<12 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 information-theoretically secure commitments where the receiver commits follow from any non-trivial elastic channel.