Users of cloud backup services expect to be able to quickly search their files through the backups across time. However, with frequent cyber-attacks on cloud systems many users prefer to encrypt their data. These two requirements conflict with each other due to a technological gap that this proposed project aims to fill.
This project aims to be hardware-agnostic but is open to some proprietary technology (e.g., secure enclaves) if it substantially improves performance. Unlike general-purpose search, a backup-oriented service has additional constraints. E.g., it is crucial to minimize user-side resource usage, which renders many approaches to encrypted search not applicable in this
Under this project we plan to formulate two sets of privacy guarantees: under the “passive adversary” ("honest-but-curious") threat model; and then under an extended model of “limited active adversary”; and aim to develop a technical solution for encrypted search that fits these requirements and constraints