Wei Jiang, Efficient and Constant-Round Secure Comparison through Function Transformation, Dynamic Group Switching and Asymmetric Computation

Summary: Within recent years, secure comparison protocols have been proposed using binary decomposition and properties of algebraic fields. These protocols have become increasingly efficient, but their performance has seemingly reached a plateau. We propose a new approach to this problem that transforms the comparison function into comparing specialized summations and takes advantage of dynamically switching domains of secret shares and asymmetric computations for intermediate calculations among the participating parties. As a consequence, according to our analysis, communication and computation costs have been brought to a very low and efficient level. Particularly, the communication costs have been considerably reduced both in order as well as the dominating term's order of magnitude. In addition, we propose a secure protocol under the malicious setting which maintains our transformation and is more efficient than the existing work for common domain sizes. About the speaker: Dr. Wei Jiang is an associate professor in the Department of Electrical Engineering and Computer Science of the University of Missouri-Columbia. He received the Bachelor's degrees in both Computer Science and Mathematics from the University of Iowa in 2002. He received the Ph.D. degree from Purdue University in 2008. His research interests mainly include secure multiparty computation and privacy-preserving data analytics. His work has been funded by the National Science Foundation, the Office of Naval Research, the National Security Agency, Google, and the University of Missouri Research Board.