Fast-to-finalize Nakamoto-like consensus

Shuyang Tang, Sherman S.M. Chow, Zhiqiang Liu, Joseph K. Liu

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearch

2 Citations (Scopus)


As the fundamental component of blockchains, proof-of-work (PoW) scheme has been widely leveraged to provide consensus for maintaining a distributed public ledger. However, the long confirmation time, and hence the slow finality rate, is far from satisfactory. Alternative paradigms with performance improvement emerge. Nevertheless, there are fewer attempts in modifying the PoW mechanism itself. We find that the slow finality rate in PoW is caused by using only one bit to measure the computational power, namely, whether the attained hash value is smaller than a given target. In this paper, we first propose Demo-of-Work (DoW), a generalized PoW which assigns the computational work with a score depending on the hash value. We also treat the bitcoin blockchain as a global “clock” to attain synchronization for ensuring that each participant takes part in DoW for roughly the same time interval for ensuring fairness. With these two tools, we construct an alternative blockchain called AB-chain which provides a significantly faster finality rate when compared with the existing PoW-based blockchains, without sacrificing communication complexity or fairness.

Original languageEnglish
Title of host publicationInformation Security and Privacy
Subtitle of host publication24th Australasian Conference, ACISP 2019 Christchurch, New Zealand, July 3–5, 2019 Proceedings
EditorsJulian Jang-Jaccard, Fuchun Guo
Place of PublicationCham Switzerland
Number of pages18
ISBN (Electronic)9783030215484
ISBN (Print)9783030215477
Publication statusPublished - 2019
EventAustralasian Conference on Information Security and Privacy 2019 - Christchurch, New Zealand
Duration: 3 Jul 20195 Jul 2019
Conference number: 24th (Proceedings)

Publication series

NameLecture Notes in Computer Science
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


ConferenceAustralasian Conference on Information Security and Privacy 2019
Abbreviated titleACISP 2019
Country/TerritoryNew Zealand
Internet address


  • Blockchain
  • Consensus
  • Cryptocurrency
  • Proof-of-work

Cite this