支持多链互操作的数据安全与隐私保护关键技术研究

2020年4月20日，国家发改委正式将区块链纳入“新基建”，将区块链定位为新技术基础设施，“万链共存”使得多链互联互通成为区块链技术发展的重要趋势。然而，现有方案在实现通用跨链需求时还存在较强的安全假设，包括过度依赖于中继可信、验证者诚实、用户的原子性操作以及可信执行环境等问题，并且对跨链过程中的敏感数据缺乏安全与隐私保护机制，极大制约了区块链技术的广泛应用，迫切需要攻克一批跨链关键技术。因此，本项目将围绕跨链技术中的如下问题展开研究：（1）研究支持多链互操作的通用跨链架构；（2）细粒度多维度管理的跨链数据访问控制机制；（3）轻量级跨链事务安全多域计算方法；（4）安全高效的跨链事务数据验证机制。本项目的研究内容及成果将解决异构链之间的安全互信以及数据隐私保护问题，最终为构建横纵贯通、覆盖数字社会的价值互联网提供技术与理论支撑。

On April 20, 2020, the National Development and Reform Commission of China officially incorporated the blockchain into the “New Infrastructure”, positioning the blockchain technology as a new technological infrastructure. “The coexistence of tens of thousands blockchains” makes multi-blockchain interoperability (i.e., cross-chain) an important trend in the future of blockchain technology. However, existing solutions on cross-chain still have strong security assumptions, such as excessive reliance on the trustworthiness of relay, verifier honesty, user's atomic operations, and trusted execution environment. Furthermore, the lack of security and privacy preservation mechanisms for sensitive data has greatly restricted the wide application of blockchain technology. Thus, there is an urgent requirement to conduct research on cross-chain technologies. To address these challenges, this project will conduct research on the following issues: (1) Research on an universal cross-chain architecture that can support multi-blockchain interoperability; (2) Cross-chain data access control mechanism for fine-grained and multi-dimensional management; (3) Lightweight and secure multi-domain computation methods for large-scale cross-chain transactions; (4) A safe and efficient cross-chain transaction verification mechanism. The results of this project will solve the problems of security mutual trust and data privacy preservation between heterogeneous blockchains, and ultimately provide technical and theoretical support for the construction of a horizontal and vertical valuable Internet covering a digital society.