This work proposes ORTOA, a family of one round trip data access protocols that hides the type of client access to efficiently address the privacy challenges caused by revealing the type of access.
Specifically, we propose three different single-round access type hiding protocols:
- ORTOA-LBL: Represents plaintext values in a binary format and encodes each bit with a secret label generated using pseudo-random functions (PRFs)
- ORTOA-TEE: Leverages the cryptographic guarantees of Trusted Execution Environments (TEE) (hardware enclaves)
- ORTOA-FHE: Leverages an existing crypto-graphic primitive, Fully Homomorphic Encryption (FHE). Due to the practical challenges of extensively multiplying FHE encrypted values, the code for this version is absent from this repository.