基于分级的PHANTOM交易一致排序协议研究  

Research on hierarchical PHANTOM transaction consistent ordering protocol

作　　者：胡班班 李鸿光 HU Banban;LI hongguang(Xi'an Traffic Engineering Institute,Xi'an Shaanxi 710300,China)

机构地区：[1]西安交通工程学院,陕西西安710300

出　　处：《西安交通工程学院学术研究》2024年第1期24-29,共6页Academic Research of Xi'an Traffic Engineering Institute

摘　　要：DAG(Directed Acyclic Graph)分布式账本是对比特币中存在的一些交易确认时间过长等问题的改进。DAG分布式账本具有交易速度快,吞吐量大等优点。DAG分布式账本的主要优点是交易效率高,交易不用打包,做轻量级的工作量证明(POW)就可以直接发布交易,但是DAG分布式账本中异步的发布交易带来了全局交易一致性排序的困难问题。PHANTOM协议是DAG分布式账本中的一种具体的协议。PHANTOM协议中交易的排序需要求解一个NP困难问题,因此不适合于实际应用。为了避免这种复杂的计算,高效的贪心算法GHOSTDAG协议是对PHANTOM协议的改进,不仅提高了吞吐量,而且增加了抵抗双花攻击的能力。GHOSTDAG协议使用连通度得分较高的链作为主链,再利用连通度得分对区块做线性排序,当连通度得分相同时,使用哈希函数打破僵局(tie-breaking),选择哈希值较小的排在前面。但是哈希函数是伪随机函数,因此这一排序不尽合理。本文提出了基于分级的PHANTOM区块一致排序协议,采用了区块分级的概念,解决了PHANTOM协议中区块排序不唯一性的问题,并且该协议排序速度更快,且排序更合理,吞吐量更大。模拟实验评估和分析表明:基于分级的PHANTOM交易一致排序协议方案的吞吐量为1300TPS,较之前的PHANTOM协议有显著的增加,并且新方案具有安全性和可扩展性。The DAG(Directed Acyclic Graph)distributed ledger is an improvement on some of the problems in Bitcoin,such as how long it takes to confirm some transactions.DAG distributed ledger has the advantages of fast transaction speed and large throughput.The main advantage of DAG distributed ledger is that it has high transaction efficiency.Transactions do not need to be packaged.Transactions can be directly published by doing lightweight workload proof(POW).However,the asynchronous publishing of transactions in DAG distributed Ledger has brought about difficulties in global transaction consistency sorting.The PHANTOM protocol is a specific protocol in the DAG distributed ledger.The sorting of transactions in the PHANTOM protocol requires solving an NP-hard problem and is therefore not suitable for practical applications.To avoid such complex calculations,the efficient greedy algorithm GHOSTDAG protocol is an improvement on the PHANTOM protocol,improving throughput and increasing resistance to double-flowed attacks.GHOSTDAG protocol uses the chain with higher connectivity score as the main chain,and then uses the connectivity score to do linear ordering for blocks.When the connectivity score is the same,hash function is used to break tie-breaking,and the chain with lower hash value is selected first.But the hash function is a pseudo-random function,so this sort doesn't make sense.Experimental evaluation and analysis show that the throughput of the hierarchical PHANTOM transaction consistent sorting protocol is 130OTPS,which is significantly higher than the previous PHANTOM protocol,and the new scheme has security and scalability.

关 键 词：DAG分布式账本 PHANTOM协议 区块排序 

分 类 号：O121.8[理学—数学] G558[理学—基础数学]