Deciding 1-solvability of distributed task is NP-hard

  • Ofer Biran
  • Shlomo Moran
  • Shmuel Zaks
Multiprocessor Systems And Concurrency
Part of the Lecture Notes in Computer Science book series (LNCS, volume 484)


We present a use of graph-theoretic concepts in fault-tolerant distributed systems.

The question of which distributed tasks can be solved by asynchronous protocols in the presence of crash failures has been investigated in recent years. Some of these studies investigate the solvability of specific tasks, providing both positive and negative results.

Given a distributed task, we associate with it certain graphs, that enable us to determine whether this task can be solved in the presence of on faulty processor ([BMZ]), and in this paper we further use this approach to study the following problem: Given a task T for N processors, how difficult is it to determine whether T can be solved in the presence of one faulty processor? We show that this problem is NP-hard for any fixed N≥3.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • Ofer Biran
    • 1
  • Shlomo Moran
    • 1
  • Shmuel Zaks
    • 1
  1. 1.Department of Computer Science TechnionHaifaIsrael

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