Research And Application Of Cross-chain Technology Based On Atomic Swap

Since the birth of Bitcoin in 2008,the blockchain,as an alternative technology to Bitcoin,has been widely used in many fields such as finance,medical treatment,and insurance.However,due to the characteristics of the blockchain technology itself,most of the blockchain applications are an independent network,and it is difficult for different blockchains to effectively circulate assets or data,so the blockchain cross-chain technology has been produced.To solve the problem of value exchange between different blockchains,in the current cross-chain technology,the most widely used is the atomic exchange technology,but the current atomic exchange technology still has problems such as low security and slow transaction speed.In response to such problems,the current atomic swap technology is improved here,and its main work is as follows:First of all,this thesis conducts in-depth research on blockchain technology and related theories,and introduced and compared blockchain cross-chain technologies such as notary mechanism,side chain/relay technology,atomic exchange technology and distributed private key technology in detail.At the same time,an in-depth study of the Hash time-locking protocol based on atomic swap technology has provided theoretical and technical support for the research and application of blockchain cross-chain technology in this article.Secondly,it analyzes the security issues of the hash time-locking protocol,and combines the Schnorr protocol and relay technology to propose an improved cross-chain protocol.The protocol introduces a relay chain as a matching party for cross-chain exchange of information,but the relay chain does not participate in the specific steps of cross-chain exchange.It only provides routing and forwarding for the two parties participating in the cross-chain exchange.Both parties perform identity authentication according to the Schnorr protocol to verify whether the routing is correct,and then complete the cross-chain exchange through the hash lock.By staticizing the cross-chain transaction information and passing it to the relay chain for off-chain matching,a solution is proposed to the security problem of the malicious participants in the hash time locking protocol creating a large number of timeout channels to block the network.Finally,in view of the low degree of decentralization and slow cross-chain speed of the existing blockchain digital asset cross-chain transactions,through the combination of the improved cross-chain protocol and smart contract technology proposed in this article,a decentralized system was designed and developed.A smart blockchain digital asset trading system.Any blockchain network that supports smart contracts can register asset blockchains on the relay chain in the system.Users can directly communicate with each asset through the routing provided by the relay chain.Blockchain smart contract nodes establish connections and complete cross-chain transactions,verifying that the improved cross-chain protocol can efficiently and stably support the system's cross-chain business in actual business scenarios.