An Observation on Non-Malleable Witness-Indistinguishability and Non-Malleable Zero-Knowledge

摘要

Ostrovsky et al. [1] gave the first definition of non-malleable witness-indistinguishable argument systems. A surprising result given by them showed this notion was incomparable with the notion of non-malleable zero-knowledge. However, they only discussed their relations in the interactive setting. In this paper, we make an observation on relation between the two notions in the non-interactive setting. We show the two notions are still incomparable: that is, there are non-malleable non-interactive zero-knowledge proof systems that are not non-malleable non-interactive witness-indistinguishable, and vice versa.