主讲：ZHAO WENBING Professor, Department of Electrical Engineering and Computer Science，Cleveland State University

时间：6月23日（星期四）上午9:00-11:00

地点：腾讯会议：816-578-520

主办：信息与通信工程学院

ZHAO WENBING教授简介：Dr. Zhao is a Professor at the Department of Electrical Engineering and Computer Science, Cleveland State University. He got his BS and MS degrees from the Physics Department in Peking University. He earned his Ph.D. at University of California, Santa Barbara in 2002. He has over 200 peer-reviewed publications and the author of the research monograph titled “From Traditional Fault Tolerance to Blockchain.” Dr. Zhao’s research spans from dependable distributed systems to human centered smart systems. His research has been funded by the US NSF, US Department of Transportation, Ohio Bureau of Workers’ Compensation, Ohio Department of Higher Education, the Ohio Development Services Agency, and Woodruff Foundation. He has delivered more than 10 keynotes, tutorials, public talks and demonstrations in various conferences, industry and academic venues. Dr. Zhao is an associate editor for IEEE Access, MDPI Computers, and PeerJ Computer Science, and a member of the editorial board of several international journals, including Applied System Innovation, Internal Journal of Parallel, Emergent and Distributed Systems, and International Journal of Distributed Systems and Technologies. He is currently an IEEE Senior Member and serves on the executive committee of the IEEE Cleveland Section.

报告主要内容：

The goal of this talk is to clarify common misconceptions regarding the blockchain technology, and pointing out some worrisome practices in the field of blockchain technology.

We first provide a brief introduction of the blockchain technology, highlighting its design principle, nuts and bolts, and the most fundamental innovation of the technology.

Next, we elaborate on a key concept regarding data immutability. In particular, it is a mistake to equate blockchain to data immutability. Data immutability can only be achieved in large-scale public blockchains where the cost becomes an insurmountable barrier for any attempt to change the data recorded in the blockchain.

The third topic we discuss is the differences between public, private, and consortium blockchains. We caution the use of private and consortium blockchains.

The last topic we argue is regarding blockchain consensus. Because the proof of work (PoW) consensus algorithm has obvious drawbacks on energy consumption, many alternative algorithms have been proposed. We single out two most egregious wrong practices: (1) selecting a small set of validators for reaching consensus, and (2) adopting traditional distributed consensus.