Hua Sun of University of North Texas

The advent of the modern information age is enabled by pervasive networked communication and computation devices, which accelerate data generation, exchange, and access at an unprecedented pace and bring security and privacy concerns to the forefront. In this talk, we will discuss three recent application scenarios where security constraints are central and study their fundamental limits through network information and coding theory.

The first problem is secure aggregation in federated learning, where a central server wishes to learn and only learn the sum of the gradient inputs of a number of users while some users may drop out and some users may collude with the server. We will characterize the optimal communication strategy for secure aggregation. The second problem is compound secure groupcast in selected broadcasting systems, where the key variables at a number of receivers are designed so that a central transmitter can securely communicate with any subset of the receivers through noiseless broadcasting. We will present new results on the tradeoff between the key storage size and the broadcast bandwidth. The third problem is conditional disclosure of secrets, where secret data is stored over the nodes of a graph and from one type of edges, we can recover the secret while from another type of edges, nothing is revealed about the secret. We will find all extremal graphs with maximum storage efficiency.

Biography:

Hua Sun received the B.E. degree in Communications Engineering from Beijing University of Posts and Telecommunications, China, in 2011, and the M.S. degree in Electrical and Computer Engineering and the Ph.D. degree in Electrical Engineering from University of California Irvine, USA, in 2013 and 2017, respectively. He is an Assistant Professor in the Department of Electrical Engineering at the University of North Texas, USA. His research interests include information theory and its applications to communications, privacy, security, and storage. Dr. Sun is a recipient of the NSF CAREER award in 2021, and the UNT College of Engineering Distinguished Faculty Fellowship in 2021. His co-authored papers received the IEEE Jack Keil Wolf ISIT Student Paper Award in 2016, and an IEEE GLOBECOM Best Paper Award in 2016.