How to Solve Consensus in the Smallest Window of Synchrony

  • Dan Alistarh
  • Seth Gilbert
  • Rachid Guerraoui
  • Corentin Travers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5218)


This paper addresses the following question: what is the minimum-sized synchronous window needed to solve consensus in an otherwise asynchronous system? In answer to this question, we present the first optimally-resilient algorithm ASAP that solves consensus as soon as possible in an eventually synchronous system, i.e., a system that from some time GST onwards, delivers messages in a timely fashion. ASAP guarantees that, in an execution with at most f failures, every process decides no later than round GST + f + 2, which is optimal.


Correct Process Failure Detector Small Window Minimum Estimate Previous Round 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Dan Alistarh
    • 1
  • Seth Gilbert
    • 1
  • Rachid Guerraoui
    • 1
  • Corentin Travers
    • 2
  1. 1.EPFL LPDLausanneSwitzerland
  2. 2.Universidad Politecnica de MadridMadridSpain

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