Blockchain Basics: Consensus
Required Readings:
‘21st Geneva Report on the World Economy – The Impact of Blockchain Technology on Finance:
Catalyst for Change’ Chapter 1 section ‘A brief history of consensus’ (pages 1 – 3); Casey, Crane,
Gensler, Johnson, and Narula (July 2018)
‘PoW, PoS and DAGs are NOT consensus protocols’ Dimitri Zhelezov, Medium (September 11, 2018)
‘POW vs. PoS: a comparison of two blockchain consensus algorithms’ edChain, Medium (June 12,
2018)
‘Fundamentals of Proof of Work’ Vorick (January 14, 2019)
Optional Readings:
‘Blockchain Technology Overview’ National Institute of Standards and Technology (October 2018)
(pages 18 – 28, section 4)
‘Consensus Algorithms’ CoinBundle Team, Medium (September 21, 2018)
‘A Survey of Distributed Consensus Protocols for Blockchain Networks’ Xiao, Zhang, Lou & Hou (April
8, 2019)
‘The Byzantine Generals problem’ Lamport, Shostak, & Pease; ACM Transactions on Programming
Languages and Systems (TOPLAS), 4(3), (July 1982) (suggested 382-387)
‘Decrypting Distributed Ledger Design – Taxonomy, Classification and Blockchain Community
Evaluation’ Ballandies, Dapp, and Pournaras (October 2018)
Study Questions/Issues to Prepare:
1) What is the Byzantine Generals problem? How does proof-of-work and mining in Bitcoin address
it?
2) What other approaches to consensus are there? What are some of the incentives and tradeoffs
of alternative consensus algorithms – proof-of-work, proof-of-stake, etc.?
3) How do economic incentives work within blockchain technology to maintain decentralized
ledgers and avoid double spending?