Bit Commitment in the Bounded Storage Model: Tight Bound and Simple Optimal Construction

摘要

In this paper, we study bit commitment in the bounded storage model (BSM). Specifically, in this paper we derive the tight lower bound on the memory size of honest players of bit commitment in the BSM. The tightness of our lower bound is shown by the fact that a certain bit commitment scheme obtained from the oblivious transfer by Ding et al. meets the bound with equality. We also give a simple and optimal construction of the bit commitment in this paper. We emphasize that our construction is simpler and easier to implement than already known any other bit commitment in the BSM.