Blockchain appeals to users for its high level of security, particularly in the financial industry. But that security depends on the honesty of more than half of its network, which can be changed by multiple factors.

Ning Zhang, assistant professor of computer science & engineering in the McKelvey School of Engineering at Washington University in St. Louis, plans to develop new defense tactics for blockchain with a four-year, $360,000 grant from the National Science Foundation. 

Specifically, Zhang and his lab will investigate how clustered power in large mining pools, heterogeneous network connectivity and malicious peer-to-peer network link manipulation can impact fundamental blockchain security, as well as the challenge of trustworthy external data feed.

The team will develop new models and analysis of consensus protocols, network connectivity and other factors in the system to study the safety and fairness of blockchain. The models will help them develop quantitative understanding of the system under various forms of network connectivity. 

“Real-world blockchain systems have shown a high level of resource centrality,” Zhang said. “The top four or five mining pools have controlled more than half of the mining power in Bitcoin.”

They also will study how to defend against network attacks against blockchain using trusted computing. They plan to develop a new data feed mechanism that addresses trustworthy data in blockchain applications. The mechanism would use the honest majority consensus to enhance the system’s resilience to attacks with false data. 

Zhang said the team will test its proposed solutions in both simulations and distributed network testbed.

The McKelvey School of Engineering at Washington University in St. Louis promotes independent inquiry and education with an emphasis on scientific excellence, innovation and collaboration without boundaries. McKelvey Engineering has top-ranked research and graduate programs across departments, particularly in biomedical engineering, environmental engineering and computing, and has one of the most selective undergraduate programs in the country. With 165 full-time faculty, 1,420 undergraduate students, 1,614 graduate students and 21,000 living alumni, we are working to solve some of society’s greatest challenges; to prepare students to become leaders and innovate throughout their careers; and to be a catalyst of economic development for the St. Louis region and beyond.

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