Secure Multi-Party Query Processing

PhD Thesis Proposal Defence


Title: "Secure Multi-Party Query Processing"

by

Mr. Qiyao LUO


Abstract:

Secure multi-party computation (MPC) has gained significant attention due to
its ability of enabling robust privacy protection for joint data analysis among
multiple organizations. However, existing MPC protocols suffer from huge
computational overhead, rendering them impractical for real-world deployments.
In this thesis, we tackle efficient MPC protocols from different perspectives.

We first improve the join operator, which is the key relational operator in
query processing. Our improvement processes all free-connex queries with linear
complexity under the three server honest majority model. It matches the
plaintext result for the query processing problem, as free-connex queries are
also the largest class of queries known to be solvable in linear time on
plaintext.

Second, we consider sublinear query time. We describe circuit constructions for
batch sampling problems, and further implement the first approximate query
processing solution that achieves amortized cost related to the sample size. It
splits the heavy computation tasks into offline and online stages and
significantly reduce the online response time of aggregation queries.

Finally, we address the challenge of performing aggregations on a large number
of participants with anonymous channels, a scenario referred to as the shuffle
model. We combine differential privacy techniques with the shuffle model,
resulting in the optimal error frequency estimation protocol with almost a
single message, providing strong privacy protection at the same time.


Date:                   Friday, 1 December 2023

Time:                   10:00am - 12:00noon

Venue:                  Room 3494
                        lifts 25/26

Committee Members:      Prof. Ke Yi (Supervisor)
                        Prof. Dimitris Papadias (Chairperson)
                        Prof. Kai Chen
                        Dr. Dimitris Papadopoulos


**** ALL are Welcome ****