CSR: Small: Collaborative Research: Towards User Privacy in Outsourced Cloud Data Services

云计算的出现带来了数据存储、访问和利用方式的范式转变。特别是，将数据外包到公共云可以享受无限的资源，为数据所有者和用户节省大量的经济成本。然而，用户隐私问题一直是广泛采用公共云技术的主要障碍。加密技术可以保护用户数据的机密性，然而，支持有效的数据利用，如对加密数据的搜索操作成为一个关键的挑战。现有的技术要么计算成本太高，要么缺乏足够的灵活性，无法被云用户在实践中采用。该项目旨在保护云中的用户隐私。它开发了一些工具，在外包云存储系统中提供有隐私保证的，可用的和高效的数据利用服务。具体而言，它通过将密码学与信息检索技术相结合来解决上述挑战，并集中在三个方面：（1）设计具有丰富功能的加密数据上的新关键字搜索方案，包括排名搜索和多关键字搜索;（2）设计使用各种结构（如图）表示的数据上的隐私保护搜索方案;（3）在移动的云环境中保护用户隐私的新方法。这项研究还包括一个原型和实验计划。确保用户隐私是公共云部署成功的基础。该项目还制定课程，并对学生进行教学和监督。该项目的材料将作为教程、软件包和一般感兴趣的出版物在网上提供。

The emergence of cloud computing brings a paradigm shift to the way that data is stored, accessed and utilized. Especially, outsourcing data to the public cloud enjoys unlimited resources with great economic savings for both data owners and users. However, user privacy concerns have been a major hurdle for the widespread adoption of the public cloud technology. Encryption techniques can protect the confidentiality of users' data, however, supporting effective data utilization such as search operations over encrypted data become a key challenge. Existing techniques are either too computationally expensive, or lack enough flexibility to be adopted by cloud users in practice. This project aims at protecting user privacy in the cloud. It develops the tools to provide privacy-assured, usable, and efficient data utilization services in outsourced cloud storage systems. Specifically, it tackles the above challenges by combining cryptography with information-retrieval techniques, and focuses on three aspects: (1) the design of novel keyword search schemes over encrypted data with rich functionalities, including ranked search and multi-keyword search; (2) the design of privacy-preserving search schemes over data that are represented using various structures, such as graphs; (3) new approaches for protecting user privacy in the mobile cloud setting. This research also includes a prototyping and experimentation plan. Ensuring user privacy is fundamental to the success of public cloud deployment. This project also develops curricula and teaches and supervises students. Materials of this project will be made available online as tutorials, software packages, and publications of general interest.