Equi-Joins Over Encrypted Data for Series of Queries
This addresses data privacy concerns for users outsourcing databases to cloud providers, offering improved security over existing methods, though it appears incremental in enhancing encryption schemes for specific database operations.
The paper tackles the problem of performing equi-joins over encrypted data in cloud databases, presenting a new encryption scheme that reduces leakage to equality of matching rows and only reveals the transitive closure of query leakages, with provable security and evaluation on the TPC-H benchmark.
Encryption provides a method to protect data outsourced to a DBMS provider, e.g., in the cloud. However, performing database operations over encrypted data requires specialized encryption schemes that carefully balance security and performance. In this paper, we present a new encryption scheme that can efficiently perform equi-joins over encrypted data with better security than the state-of-the-art. In particular, our encryption scheme reduces the leakage to equality of rows that match a selection criterion and only reveals the transitive closure of the sum of the leakages of each query in a series of queries. Our encryption scheme is provable secure. We implemented our encryption scheme and evaluated it over a dataset from the TPC-H benchmark.