PoTA: A hybrid consensus protocol to avoid miners' collusion for BaaS platform

【Author】 Wang, Kaiyu; Tu, Zhiying; Ji, Zhenzhou

【Source】PEER-TO-PEER NETWORKING AND APPLICATIONS

【Abstract】The emergence of the blockchain-as-a-service (BaaS) platform reduces the application barrier of blockchain technology. However, in BaaS, the transaction processing demand generated by BaaS users is continuous isolating from the transaction processing capability that comes from blockchain miner community. This results in the phenomenon that miner community spontaneously reduces the transaction processing capacity to obtain higher revenue, which is called the miners' collusion. The BaaS platform requires a new consensus protocol that prevent the miners' collusion while remain the security and immutability of blockchain. Based on this challenge, in this article, we propose a hybrid consensus protocol for BaaS called the Proof-of-Transaction Amount (PoTA). First, we theoretically analyze and formally define the miners' collusion. The existence of Nash-equilibrium collusion strategy has been proven. Second, the calculation method of the miner's effective collusion strategy space is provided to help determine whether the BaaS is facing the threat of collusion. Third, by organizing a transaction packaging committee (TPC) based on transaction amount, PoTA successfully avoids single-identity miners who have greater effective collusion strategy space obtaining the authority of transaction packaging. In the meanwhile, we redefine the reference relationship of blocks to enable cross-verification of PoW and PoS consensus. Finally, we prove our protocol can effectively avoid the occurrence of the miners' collusion. Control experiments prove the outperforms security and performance of PoTA in the comparison with PoW, PoS and other hybrid protocols.

【Keywords】Blockchain-as-a-Service; Miners' collusion; Game theory; Consensus protocol

【标题】PoTA：避免矿工串通 BaaS 平台的混合共识协议

【摘要】区块链即服务（BaaS）平台的出现降低了区块链技术的应用壁垒。但在 BaaS 中，BaaS 用户产生的交易处理需求与来自区块链矿工社区的交易处理能力是持续隔离的。这就导致了矿工社区自发降低交易处理能力以获取更高收益的现象，称为矿工合谋。 BaaS 平台需要一种新的共识协议，以防止矿工串通，同时保持区块链的安全性和不变性。基于这一挑战，在本文中，我们提出了一种用于 BaaS 的混合共识协议，称为交易量证明（PoTA）。首先，我们从理论上分析并正式定义矿工合谋。纳什均衡共谋策略的存在已被证明。其次，提供矿工有效合谋策略空间的计算方法，帮助判断 BaaS 是否面临合谋威胁。第三，通过根据交易金额组织交易打包委员会（TPC），PoTA成功避免了拥有更大有效合谋策略空间的单一身份矿工获得交易打包权限。同时，我们重新定义了区块的引用关系，实现了 PoW 和 PoS 共识的交叉验证。最后，我们证明了我们的协议可以有效避免矿工合谋的发生。控制实验证明，与 PoW、PoS 和其他混合协议相比，PoTA 的安全性和性能优于 PoTA。

【关键词】区块链即服务；矿工勾结；博弈论；共识协议

【收录时间】2022-08-23

【文献类型】Article; Early Access

【论文大主题】共识机制

【论文小主题】新共识机制提出

【影响因子】3.488