Fast Indulgent Consensus with Zero Degradation

  • Partha Dutta
  • Rachid Guerraoui
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2485)


This paper presents a new consensus algorithm for the asynchronous message passing system model augmented with an unreliable failure detector abstraction. Our algorithm (a) matches all known consensus lower bounds on (1) failure detection, i.e., Ω, (2) resilience, i.e., a majority of correct processes, and (3) latency, i.e., two communication steps for a global decision in nice runs (when no process crashes and the failure detection is reliable), and (b) has the following zero degradation flavor: in every stable run of the algorithm (when all failures are initial crashes, and failure detection is reliable), two communication steps are sufficient to reach a global decision.

The zero degradation flavor is particularly important when consensus is used in a repeated form: failures in one consensus instance do not impact performance of future consensus instances.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Partha Dutta
    • 1
  • Rachid Guerraoui
    • 1
  1. 1.Distributed Programming Laboratory Swiss Federal Institute of Technology in LausanneSwitzerland

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