A Survey on Consensus Fairness in Blockchains

PhD Qualifying Examination


Title: "A Survey on Consensus Fairness in Blockchains"

by

Mr. Weijie SUN


Abstract:

Blockchain technology has revolutionized distributed systems by enabling 
decentralized consensus among untrusted participants. However, while existing 
research primarily focuses on system performance and security, the fairness 
issues in consensus mechanisms have received relatively less attention. These 
fairness concerns among blockchain participants directly impact user 
participation incentives and potentially damage the system stability in both 
permissionless and permissioned blockchains.

This survey provides a comprehensive review of consensus fairness in 
blockchain systems. We first identify three primary consensuses in 
blockchains facing fairness issues: Proof-of-Work (PoW), Proof-of-Stake 
(PoS), and Byzantine Fault Tolerance (BFT). Specifically, we discuss the 
unique fairness issues under each consensus, including the biased leader 
election and selfish mining attack in PoW, the stake concentration issue and 
block withholding towards Maximal Extractable Value (MEV) in PoS, and the 
transaction ordering fairness in BFT. Then, we analyze existing solutions and 
their trade-offs between fairness and other system properties such as 
performance and security. Finally, we discuss the challenges and limitations 
of existing solutions, identify promising research directions in achieving 
consensus fairness in blockchain systems.


Date:                   Wednesday, 18 December 2024

Time:                   9:00am - 11:00am

Venue:                  Room 3494
                        Lifts 25/26

Committee Members:      Prof. Lei Chen (Supervisor)
                        Prof. Qiong Luo (Chairperson)
                        Dr. Shimin Di
                        Prof. Ke Yi