The concept of a blockchain was invented by Satoshi Nakamoto to maintain a distributed ledger for an electronic cash system, Bitcoin. Even though very secure, blockchain systems have serious deficiencies in some important performance measures, including transaction throughput, confirmation latency and confirmation reliability. To this end, distributed ledger technology with underlying directed acyclic graph (DAG) structure has been proposed to overcome the scalability bottleneck of blockchain systems. 
 
In this talk, we present Canonchain, a new DAG based distributed ledger technology. We provide rigorous analysis to the consensus algorithm, which utilizes non-anonymous reputable entities, called witnesses.  Our new protocol can achieve 1) more than 2000 transactions per second (TPS); 2) less than 20 seconds transaction confirmation time and 3) eventual total ordering of all transactions.

Dr. Lei Zhang is a Co-Founder of Nakamoto & Turing Labs. He is also an adjunct professor at Columbia University in the City of New York. Prior to that, he was a staff engineer at Qualcomm Research and a technical lead in autonomous driving team. Dr. Zhang received his Ph.D. degree from Northwestern University and B.E. degree from Tsinghua University, both in Electrical Engineering. Dr. Zhang has published many papers in top-ranking conferences and journals. His paper “Capacity of Gaussian channels with duty cycle and power constraints” was awarded the best Student Paper Award of the 2011 International Symposium on Information Theory (ISIT). Dr. Zhang has broad research interests, including blockchain, information theory, machine learning, and computer vision.