TWC: Small: Building Efficient and Accountable Multi-User ORAM Systems for Protecting Data Access Patterns

基于云的数据共享越来越受欢迎，但隐私意识也越来越强。 云计算的持续增长将需要协调这些问题。 虽然数据加密可以提供一些保护，但是已经表明，即使对加密数据的访问模式也可以泄露私人信息（例如，知道加密的数据由疾病控制中心上传并且随后由特定用户访问表明该用户关注某种疾病，即使具体细节是未知的。 在实际场景中，存在多个用户和云服务器，用户和服务器之间可能互不信任，如何保护数据访问模式缺乏研究和理解。 本研究项目的第一个目标是加深对保护数据访问模式的挑战和附带的安全风险的理解，具体而言，本项目将开发保护数据访问模式的正式模型和初步方法，为开发保护数据访问模式的新解决方案和严格评估解决方案的安全属性奠定坚实的基础。 该项目还计划为外包数据提供可证明安全性的、不经意的、高效的和负责任的多用户访问协议，以便在选定的一组代表性对手模型下保留每个用户的访问模式。

Cloud-based data sharing is increasing in popularity, but there is also an increasing privacy consciousness. Continued growth in cloud computing will require reconciling these issues. While data encryption can provide some protection, it has been shown that even access patterns to encrypted data can reveal private information (e.g., knowing encrypted data was uploaded by the Centers for Disease Control and later accessed by a particular user suggests that the user is concerned about some disease, even if the specifics are not known.) There is a lack of study and understanding of how to protect data access pattern in practical scenarios, where there are multiple users and cloud servers and the users and server may not trust each other. The first objective of the research project is to deepen the understanding of the challenges in protecting data access patterns as well as the collateral security risks.Specifically, this project will develop formal models for protecting data access patterns and initial approaches to that protection, laying a solid foundation for developing novel solutions to protect data access patterns and strictly evaluating the security properties of the solutions. The project also plans to deliver security-provable, oblivious, efficient and accountable multi-user access protocols to outsourced data, for the sake of preserving each individual user's access pattern under a selected set of representative adversary models.