We give a new proof of the existence of $$O(n^{\epsilon })$$O(nϵ)-round public-coin concurrent zero-knowledge arguments for $$\mathcal {NP}$$NP, where $$\epsilon >0$$ϵ>0 is an arbitrary constant. The security is proven in the plain model under the assumption that collision-resistant hash functions exist. The existence of such concurrent zero-knowledge arguments was previously proven by Goyal (STOC’13) in the plain model under the same assumption. In the proof, we use a new variant of the non-black-box simulation technique of Barak (FOCS’01). An important property of our simulation technique is that the simulator runs in a “straight-line” manner in the fully concurrent setting. Compared with the simulation technique of Goyal, which also has such a property, the analysis of our simulation technique is (arguably) simpler.

中文翻译：

---

重新审视完全并发设置中的非黑盒模拟

我们为 $$\mathcal {NP}$$NP 的 $$O(n^{\epsilon })$$O(nϵ)-round public-coin 并发零知识参数的存在提供了新的证明，其中 $ $\epsilon >0$$ϵ>0 是一个任意常数。在假设存在抗碰撞散列函数的情况下，在普通模型中证明了安全性。Goyal (STOC'13) 之前在相同假设下的普通模型中证明了这种并发零知识论点的存在。在证明中，我们使用了 Barak (FOCS'01) 的非黑盒模拟技术的新变体。我们的模拟技术的一个重要特性是模拟器在完全并发的设置中以“直线”方式运行。与同样具有这种特性的 Goyal 模拟技术相比，我们对模拟技术的分析（可以说）更简单。