基于门限密码方案的共识机制

针对比特币的PoW(proof of work)共识机制中资源消耗巨大、系统性能存在瓶颈和“公地悲剧”问题，从博弈论的角度分析了比特币系统后期只有交易费奖励所带来的“公地悲剧”现象，提出了基于门限密码方案的共识机制(a consensus mechanism based on threshold cryptography, TCCM).首先，新共识协议引入了节点保证金的思想，提出了一种基于门限群签名理论的保证金模型.该模型既能够确保保证金的安全，又为节点诚实地记账提供保障.其次，利用门限加密的思想构造了记账权竞价模型来产生区块链记账节点，这能够保证记账权竞价环境的公平性和记账节点产生的随机性.同时，在原有的区块奖励基础上，设计了新的激励机制，使得更多的节点能够参与共识的全过程.最后，安全性和性能分析结果表明，该共识机制既有效地降低了资源消耗，又提高了交易处理效率，使得整个区块链系统变得更加安全可靠.

Consensus Mechanism Based on Threshold Cryptography Scheme

Aiming at the huge resource consumption, the bottleneck of the system performance and “tragedy of the commons” in the PoW(proof of work) consensus mechanism of bitcoin, we analyze the “tragedy of the commons” caused by only transaction fees rewarding in the later stage of the bitcoin system from the perspective of game theory and propose a consensus mechanism based on threshold cryptography (TCCM) in this paper. Firstly, the new consensus protocol introduces the idea of margin, and proposes a margin model based on threshold group signature theory. The model not only ensures the security of the margin, but also provides a guarantee for the node to honestly produce the block. Secondly, a bidding model of the right of accounting is also constructed using the idea of threshold encryption to generate a node that can produce the block. This model can guarantee the fairness of the bidding model environment and select the accounting node randomly. Then, a new incentive mechanism is redesigned based on the original block rewards so that more nodes can participate in the consensus process. Finally, the results of security and performance analysis show that TCCM not only effectively reduces the huge resource consumption, but also improves the transaction processing efficiency and makes the whole blockchain system more secure.