A Study on Privacy Protection of Cross-Chain Transactions Based on Improved Notary Mechanisms

Blockchain technology is widely used in the field of e-commerce, but with the increasing variety of blockchains, there is a problem of how to interact with different blockchain assets. To address this issue, a new e-commerce transaction model based on an improved notary mechanism is proposed. Firstly, the model analyzes the interest interaction modes of buyers, sellers, and logistics companies through the e-commerce supply chain process. Based on this analysis, a three-party supervision transaction mechanism based on BLS (Boneh-Lynn-Shacham) signatures is proposed. The mechanism is designed so that the buyer, seller, and logistics company act as notaries for each other, forming a circular cross-chain supervision where the buyer is responsible for the seller, the seller is responsible for the logistics company, and the logistics company is responsible for the buyer. This ensures trustworthy cross-chain transactions under the premise of mutual distrust among the three parties.Then, the model combines elliptic curve cryptography and symmetric encryption to achieve privacy protection of the buyer’s data on the blockchain. Finally, experimental results and scheme comparisons demonstrate that the proposed model has a low probability of malicious attacks and a high cost of attacks. Furthermore, the encryption and decryption efficiency of the used algorithm is superior to other comparison schemes, meeting the requirements of daily e-commerce activities.