论文标题
GHAST：通过自适应加权块中纳卡摩共识中的破坏确认延迟屏障
GHAST: Breaking Confirmation Delay Barrier in Nakamoto Consensus via Adaptive Weighted Blocks
论文作者
论文摘要
区块链技术是从Nakamoto的比特币系统发起的，具有在互联网规模的分散政党之间建立安全共识的功能，即不依赖任何集中的信任政党。如今，区块链系统在各个字段中找到应用程序。但是，表现越来越多地成为瓶颈，尤其是当保留无许可的参与以进行全面权力下放时。 在这项工作中，我们提出了一种名为Ghast（贪婪最重的自适应子树）的新共识协议，该协议在树木图结构（即带有嵌入树嵌入树的有向的无循环图（DAG））中组织块，该块允许快速且同意的块生成。 GHAST协议同时达到了对数界限的可将其保证和较低的确认延迟。更具体地说，对于最大延迟$ d $和对抗计算功率，从50 \％界限，GHAST保证确认$ \ ge 1- \ ge 1- \ varepsilon $ $ o（d \ cdot \ log \ log（1/\ varepsilon））$。当没有可观察到的攻击时，Ghast只需要$ 3D $的时间就可以在比特币中的六块票房确认的同一信心水平上实现确认，而比特币中的比特币大约需要$ 360D $。
Initiated from Nakamoto's Bitcoin system, blockchain technology has demonstrated great capability of building secure consensus among decentralized parties at Internet-scale, i.e., without relying on any centralized trusted party. Nowadays, blockchain systems find applications in various fields. But the performance is increasingly becoming a bottleneck, especially when permissionless participation is retained for full decentralization. In this work, we present a new consensus protocol named GHAST (Greedy Heaviest Adaptive Sub-Tree) which organizes blocks in a Tree-Graph structure (i.e., a directed acyclic graph (DAG) with a tree embedded) that allows fast and concurrent block generation. GHAST protocol simultaneously achieves a logarithmically bounded liveness guarantee and low confirmation latency. More specifically, for maximum latency $d$ and adversarial computing power bounded away from 50\%, GHAST guarantees confirmation with confidence $\ge 1-\varepsilon$ after a time period of $O(d\cdot \log(1/\varepsilon))$. When there is no observable attack, GHAST only needs $3d$ time to achieve confirmation at the same confidence level as six-block-confirmation in Bitcoin, while it takes roughly $360d$ in Bitcoin.
