Safe Permissionless Consensus

Youer Pu, Lorenzo Alvisi, Ittay Eyal

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


Nakamoto's consensus protocol works in a permissionless model, where nodes can join and leave without notice. However, it guarantees agreement only probabilistically. Is this weaker guarantee a necessary concession to the severe demands of supporting a permissionless model? This paper shows that, at least in a benign failure model, it is not. It presents Sandglass, the first permissionless consensus algorithm that guarantees deterministic agreement and termination with probability 1 under general omission failures. Like Nakamoto, Sandglass adopts a hybrid synchronous communication model, where, at all times, a majority of nodes (though their number is unknown) are correct and synchronously connected, and allows nodes to join and leave at any time.

Original languageEnglish
Title of host publication36th International Symposium on Distributed Computing, DISC 2022
EditorsChristian Scheideler
ISBN (Electronic)9783959772556
StatePublished - 1 Oct 2022
Event36th International Symposium on Distributed Computing, DISC 2022 - Augusta, United States
Duration: 25 Oct 202227 Oct 2022

Publication series

NameLeibniz International Proceedings in Informatics, LIPIcs


Conference36th International Symposium on Distributed Computing, DISC 2022
Country/TerritoryUnited States


  • Consensus
  • Deterministic Safety
  • Nakamoto
  • Permissionless

All Science Journal Classification (ASJC) codes

  • Software


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