Lower Bound on the Step Complexity of Anonymous Binary Consensus

  • Hagit AttiyaEmail author
  • Ohad Ben-BaruchEmail author
  • Danny HendlerEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9888)


Obstruction-free consensus, ensuring that a process running solo will eventually terminate, is at the core of practical ways to solve consensus, e.g., by using randomization or failure detectors. An obstruction-free consensus algorithm may not terminate in many executions, but it must terminate whenever a process runs solo. Such an algorithm can be evaluated by its solo step complexity, which bounds the worst case number of steps taken by a process running alone, from any configuration, until it decides.

This paper presents a lower bound of \(\varOmega (\log n)\) on the solo step complexity of obstruction-free binary anonymous consensus. The proof constructs a sequence of executions in which more and more distinct variables are about to be written to, and then uses the backtracking covering technique to obtain a single execution in which many variables are accessed.


Space Complexity Shared Variable Failure Detector Consensus Algorithm Step Complexity 
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 2016

Authors and Affiliations

  1. 1.Department of Computer ScienceTechnionHaifaIsrael
  2. 2.Department of Computer-ScienceBen-Gurion University of the NegevBeer-ShevaIsrael

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