A full-stack study of blockchains on security, performance, and incentive

Blockchains have attracted colossal attention recently and are impacting various research areas while encountering several stiff challenges. This thesis makes contributions to blockchains by addressing three vital challenges in security, performance, and incentive. First, the security challenge arises when malicious parties are beyond the threshold and launch a successful safety attack. A novel action called forensics is designed to detect the attackers with irrefutable proof. Moreover, the forensic support metric is mathematically formalized and systematically characterized for Byzantine fault-tolerant (BFT) protocols such as PBFT, HotStuff, and VABA, all of which possess strong forensic support. On the contrary, Algorand, a player replaceable protocol, is shown to have no forensic support. A novel protocol with both player replaceability and strong forensic support is presented to demonstrate the feasibility of having both properties in one BFT protocol. Next, the performance challenge refers to the consensus layer bottleneck of permissionless blockchains. This bottleneck is removed by a novel consensus protocol called Prism, implemented in clients with a flexible interface to support smart contracts. Experiments show empirical evidence that Prism has removed the consensus layer performance bottleneck. Finally, the incentive challenge is the phenomenon of token compounding in proof-of-stake (PoS) blockchains which leads to unfair reward distribution and discourages parties with a small number of tokens from joining PoS blockchains. A metric of fair reward distribution called equitability is mathematically formalized and analyzed for extant reward distribution mechanisms. Furthermore, a novel mechanism called the geometric reward is introduced and proved to be the most equitable.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Computer Science

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2022

Author dc:creator

• Wang, Gerui

Contributors dc:contributor

• Viswanath, Pramod
• Rosu, Grigore
• Miller, Andrew
• Ren, Ling
• Nayak, Kartik

• blockchain
• consensus
• incentive
• blockchain performance
• smart contract
• blockchain forensics

Statement dc:rights

• Copyright 2022 Gerui Wang

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/115493

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F115493