Cloud computing is a ubiquitous paradigm responsible for a fundamental change in the way distributed computing is performed. The possibility to outsource the installation, maintenance and scalability of servers, added to competitive prices, makes this platform highly attractive to the computing industry. Despite this, privacy guarantees are still insufficient for data processed in the cloud, since the data owner has no real control over the processing hardware. This work proposes a framework for database encryption that preserves data secrecy on an untrusted environment and retains searching and updating capabilities. It employs order-revealing encryption to perform selection with time complexity in Θ(logn), and homomorphic encryption to enable computation over ciphertexts. When compared to the current state of the art, our approach provides higher security and flexibility. A proof-of-concept implementation on top of the MongoDB system is offered and applied in the implementation of some of the main predicates required by the winning solution to Netflix Grand Prize.

中文翻译：

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搜索加密数据库的框架

云计算是一种普遍存在的范式，它对分布式计算的执行方式进行了根本性的改变。将服务器的安装、维护和可扩展性外包的可能性，加上具有竞争力的价格，使得该平台对计算行业极具吸引力。尽管如此，对于在云中处理的数据，隐私保证仍然不足，因为数据所有者无法真正控制处理硬件。这项工作提出了一个数据库加密框架，该框架在不受信任的环境中保留数据保密性并保留搜索和更新功能。它采用顺序显示加密来执行时间复杂度为 Θ(logn) 的选择，并采用同态加密来实现对密文的计算。与目前最先进的技术相比，我们的方法提供了更高的安全性和灵活性。提供了基于 MongoDB 系统的概念验证实现，并将其应用于 Netflix 大奖获胜解决方案所需的一些主要谓词的实现。