| With the rapid development of blockchain technology,realizing asset interaction between different blockchains has become an inevitable demand.And cross-chain technology is of great significance for value sharing among chains.However,the current cross-chain technology is still in the preliminary exploration stage,and it is difficult to cope with the increasing interaction requirements and application scenarios.On the one hand,the current cross-chain technologies mainly focus on native assets and have some limitations in terms of security and efficiency,making it difficult to meet the future demand for large-scale and low-cost cross-chain interactions.On the other hand,with the development of blockchain,assets in blockchain also tend to be diverse.Cross-chain content is no longer limited to native assets only,posing new challenges to cross-chain technology.Non-fungible token as a new type of on-chain asset has attracted a lot of attention in recent years,but there has been no research on the cross-chain interaction of this asset.Therefore,this thesis explores cross-chain solutions that apply to different types of assets,with the following main work:1.A secure and efficient atomic cross-chain commitment model for fungible tokens is proposed.To meet increasing cross-chain requirements for native assets in terms of security and efficiency at this stage,this thesis focuses on atomic swap technology to realize asset exchange.Cross-chain interactions are performed in phases,and each phase can only execute a specific operation and trigger asset transfer through transaction state,thus solving the security problems in the traditional atomic swap process due to the timeouts and fork fraud.Meanwhile,to reduce the cost of cross-chain interaction and improve the efficiency of interaction,the reuse of relevant smart contracts and submission information is allowed and strategies are used to submit the verification information.Therefore,the cost of contracts operations and storage during cross-chain interactions are significantly reduced.Finally,the superiority of the proposed model in this thesis is verified by experiments in terms of performance and security.2.A non-fungible asset transfer model based on a notary group is proposed.To fill the gap in cross-chain technology for non-fungible tokens,this thesis accomplishes the transfer of assets between chains with the help of a notary group.The use of smart contracts under the common control of multiple notaries enables effective escrow of non-fungible assets on the chain,and the guarantee mechanism and random election process ensure the reliability of notaries to legally mint tokens in the receiving chain.The above measures guarantee the atomicity of the cross-chain interaction process.In order to enhance the fairness and activeness of the notary group,a reward and punishment mechanism based on reputation value and appropriate access and withdraw rules are set,which reduces the influence of the centralization of a single notary.Finally,the experiments were conducted to verify the stability of the proposed model and the effectiveness of the reputation design when coordinating across chains.3.Cross-chain system applicable to multiple types of assets is designed and implemented.To make the reader more aware of the cross-chain solutions proposed in this thesis for different types of assets,a corresponding cross-chain interaction system is carried out.It can support atomic exchange of fungible assets,transfer of non-fungible assets across chains,and statistical query for personal information,which makes cross-chain interaction no longer limited to model design and experiments,and has certain practical significance for promoting the application of cross-chain solutions. |
