区块链链下通道研究综述

Overview on Blockchain Off-Chain Channels

近年来,随着比特币、以太坊等数字货币的流行,区块链也受到了各界广泛关注.然而,区块链的三元(可扩展性、安全性、去中心化)悖论限制了其进一步发展,尤其区块链的可扩展性问题致使其交易速率远低于VISA等中心化服务平台.链下通道作为对区块链的扩展,能够有效提高区块链的可扩展性,增大区块链的适用范围.本文首先研究了区块链可扩展性的影响因素,总结了Layer-1扩容和Layer-2扩容的基本概念,并解释了链下通道的基本流程.其次,根据通道中参与者的数量将其分为双方支付通道和多方支付通道.对于双方支付通道,依据实现原理和功能的不同,又将其分为普通支付通道、基于哈希时间锁的支付通道、虚拟通道、支付通道再平衡等类别.另外,介绍了匿名支付通道.进一步,对于每一类通道,总结了其基本流程,分析了典型案例,并指出其存在的优缺点.最后,从应用、监管、奖惩等层面指出了链下通道的未来发展方向.

In recent years,with the popularity of cryptocurrencies like Bitcoin and Ethereum,blockchain has garnered widespread attention across various sectors.Nevertheless,the blockchain's trilemma--scalability,security,and decentralization--has also limited its further development,particularly the scalability issue,which has resulted in transaction speeds far below those of centralized service platforms like VISA.Off-chain channels,as an extension of blockchain,have proven effective in enhancing blockchain scalability and expanding its range of applications.Firstly,this study examines the factors affecting blockchain scalability,summarizes the fundamental concepts of Layer-1 and Layer-2 scaling,and elucidates the basic processes of off-chain channels.Secondly,based on the number of participants in the channels,they are categorized into two types:two-party payment channels and multi-party payment channels.Regarding two-party payment channels,they are further classified into regular payment channels,hash time lock contract(HTLC)-based payment channels,virtual channels,and payment channel rebalancing,depending on their implementation principles and functions.An additional category is anonymous payment channels.Furthermore,for each category of channels,their basic processes are outlined,typical cases are analyzed,and their advantages and disadvantages are identified.Lastly,this study highlights the future development directions of off-chain channels from the perspectives of applications,regulation,and incentives.