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arXiv · 1508.02448

Equivalence-based Security for Querying Encrypted Databases: Theory and Application to Privacy Policy Audits

Omar Chowdhury·Deepak Garg·Limin Jia·Anupam Datta
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Abstract

Motivated by the problem of simultaneously preserving confidentiality and usability of data outsourced to third-party clouds, we present two different database encryption schemes that largely hide data but reveal enough information to support a wide-range of relational queries. We provide a security definition for database encryption that captures confidentiality based on a notion of equivalence of databases from the adversary's perspective. As a specific application, we adapt an existing algorithm for finding violations of privacy policies to run on logs encrypted under our schemes and observe low to moderate overheads.

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Omar Chowdhury, Deepak Garg, Limin Jia, Anupam Datta. 2015-08-10. Equivalence-based Security for Querying Encrypted Databases: Theory and Application to Privacy Policy Audits. https://arxiv.org/abs/1508.02448

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