We present parallel proof-of-work with DAG-style voting, a novel proof-of-work cryptocurrency protocol that, compared to Bitcoin, provides better consistency guarantees, higher transaction throughput, lower transaction confirmation latency, and higher resilience against incentive attacks. The superior consistency guarantees follow from implementing parallel proof-of-work, a recent consensus scheme that enforces a configurable number of proof-of-work votes per block. Our work is inspired by another recent protocol, Tailstorm, which structures the individual votes as tree and mitigates incentive attacks by discounting the mining rewards proportionally to the depth of the tree. We propose to structure the votes as a directed acyclic graph (DAG) instead of a tree. This allows for a more targeted punishment of offending miners and, as we show through a reinforcement learning based attack search, makes the protocol even more resilient to incentive attacks. An interesting by-product of our analysis is that parallel proof-of-work without reward discounting is less resilient to incentive attacks than Bitcoin in some realistic network scenarios.

翻译：我们提出一种结合有向无环图（DAG）结构投票的并行工作量证明机制——该新型加密货币协议相比比特币，在一致性保障、交易吞吐量、交易确认延迟及对激励攻击的抵御能力方面均具有显著优势。其优秀的一致性保障源于实现了一种新型共识方案：通过每区块强制要求可配置数量的工作量证明投票。本工作受近期Tailstorm协议启发——该协议将投票组织为树形结构，并通过按树深度比例递减挖矿奖励来抑制激励攻击。我们提出采用有向无环图（DAG）替代树形结构组织投票，从而实现对恶意矿工更具针对性的惩罚机制。通过基于强化学习的攻击搜索验证，该方案在抵御激励攻击方面展现出更强的鲁棒性。有趣的分析副产品表明：在某些现实网络场景中，未设置奖励折扣的并行工作量证明机制对比特币的激励攻击抵御能力更弱。