Join us at noon on Monday, March 28 in the Coda building or by Zoom as Ling Ren, an assistant professor in the Computer Science Department at University of Illinois, Urbana-Champaign, presents a lecture to SCP’s faculty and students. More information on the talk and the zoom link are below.
We have recently seen increasing research and deployment of Byzantine fault-tolerant distributed systems (sometimes referred to as blockchains). While the core of these systems traces back to the classic Byzantine General’s problem, significant gaps remain in the algorithmic foundation of these practical systems. In this talk, I will present recent works from my group aimed at filling these gaps. First, we observe that practical systems prioritize good-case efficiency while theoretical research so far has focused on worst-case efficiency. We give new protocols with optimal good-case latency or communication cost along with tight lower bounds. This in turn leads to a solution to the long-standing open problem on the worst-case communication of Byzantine agreement. Second, practical systems work with large blocks of data. We introduce a new fundamental primitive called Data Dissemination and use it to improve a wide range of important problems in distributed computing and cryptography including verifiable secret sharing, distributed randomness beacon, and distributed key generation. Lastly, our understanding of the more recent longest-chain paradigm is still limited in many ways. I will discuss our progress on a more accessible, practical, and unifying algorithmic foundation for longest-chain protocols and its implications.
Ling Ren is an assistant professor in the Department of Computer Science at the University of Illinois at Urbana-Champaign. Prior to joining the University of Illinois, he obtained his Ph.D. from MIT and worked at VMware Research. His research interests include security, cryptography, and distributed algorithms. He has won several awards including NSF CAREER Award, Google privacy research award, VMware Early Career Faculty Grant, Best Paper Runner-Up and Best Student Paper at CCS, and Top Picks in Hardware and Embedded Security.