论文标题
基于LDPC代码的区块链协议的分析
Analysis of a blockchain protocol based on LDPC codes
论文作者
论文摘要
在区块链数据可用性攻击（DAA）中，恶意节点发布了一个块标头，但保留了包含无效交易的块的一部分。诚实的完整节点可以下载和存储完整的区块链，它知道某些数据不可用，但他们没有正式的方法来证明其向点点节点，即资源有限并且无法访问整个区块链数据的节点。反对这些攻击的常见解决方案利用线性错误纠正代码来编码块内容。最近的一种称为SPAR的协议使用编码的默克尔树和低密度奇偶校验检查代码来对抗DAA。在本文中，我们表明该协议的安全性不如对抗性成功概率的重新定义。结果，我们表明，对于参数的某些现实选择，光节点下载的数据总数比竞争对手解决方案可获得的数据大。
In a blockchain Data Availability Attack (DAA), a malicious node publishes a block header but withholds part of the block, which contains invalid transactions. Honest full nodes, which can download and store the full blockchain, are aware that some data are not available but they have no formal way to prove it to light nodes, i.e., nodes that have limited resources and are not able to access the whole blockchain data. A common solution to counter these attacks exploits linear error correcting codes to encode the block content. A recent protocol, called SPAR, employs coded Merkle trees and low-density parity-check codes to counter DAAs. In this paper, we show that the protocol is less secure than claimed, owing to a redefinition of the adversarial success probability. As a consequence we show that, for some realistic choices of the parameters, the total amount of data downloaded by light nodes is larger than that obtainable with competitor solutions.
