区块链跨链技术研究综述

doi:10.11959/j.issn.2096-3750.2022.00301

Abstract

Abstract:

With the in-depth development and continuous innovation of blockchain technology, blockchain networks suitable for different application scenarios and design requirements have emerged as the times require, the mutual independence of blockchains inevitably forms the value island effect of the blockchain.Cross-chain technology is an important technical means to realize industrial collaboration and value circulation between different blockchains and improve their interoperability and scalability.Firstly, the basic concept of cross-chain was introduced.And then, the technical difficulties of cross-chain, the technical characteristics of the main mechanism of cross-chain, and the security of cross-chain were analyzed in detail.Finally, the challenges faced by the current cross-chain technology were introduced, and the future development of cross-chain technology was prospected.

Key words: blockchain, cross-chain, notary, side chain, Hash-locking

CLC Number:

TP309

Chuannian SHEN. Review on cross-chain technology research of blockchains[J]. Chinese Journal on Internet of Things, 2022, 6(4): 183-196.

Figures/Tables 2

References 75

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模式	优点	缺点
托管模式	托管模式不需要对现有协议进行任何改造；	单一托管模式存在过度中心化风险；
	联盟托管模式中公证人联盟的诚实度越高，系统的安全性越高	联盟托管模式中公证人联盟仍存在共谋风险
SPV模式	SPV模式在进行交易验证时，由于只验证区块头信息，无须验证	需要在兼容现有主链的情况下对协议进行改造；
	所有交易记录，可提高交易处理速度；	SPV 模式由于只保存了区块头信息，无法验证全部交易记
	通过将小额零散交易转移到侧链进行，一方面可以缓解主链的交	录，存在被恶意攻击的安全风险；
	易负担，提高交易效率，另一方面可以有效保护主链上大额资产	需要对主链进行软分叉
	账户的地址；
	可扩展主链的功能，提供更多的跨链应用场景
驱动链模式	诚实矿工的参与数量越多，系统的安全性越高	需要在兼容现有主链的情况下对协议进行改造；
		需要对主链进行软分叉
混合模式	主链和侧链使用不同的模式，通过整合多种模式的优点，弥补了	需要在兼容现有主链的情况下对协议进行改造；
	单一模式的不足	需要对主链进行软分叉

跨链机制性能	公证人机制	侧链/中继	哈希锁定	分布式私钥控制	公证人+侧链混合机制
互操作性	所有	所有（所有链都须支持中继，否则只支持单向操作^[27]）	只支持交叉依赖	所有	所有
信任模型	多数公证人诚实	所有链不会失效	所有链不会失效	所有链不会失效	混合模式
是否可用于跨链交换	是	是	是	是	是
是否可用于跨链资产转移	是（需要公证人一直	是	否	是	是
	受信任）
是否可用于跨链预言机	是	是	不能直接使用	是	是
是否可用于跨链资产抵押	是（需要公证人一直	是	大多数支持	是	是
	受信任）
跨链实现难度	中	高	低	中	高
跨链交易效率	低	低	中	中	高
跨链安全性	低	低	中	中	高
代表项目	Interledger Palletone	BTC Relay Cosmos	闪电网络	Wanchain Fusion	Ether Universe Sifchain

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