Time-message trade-offs for the weak unison problem

Extended abstract
  • Amos Israeli
  • Evangelos Kranakis
  • Danny Krizanc
  • Nicola Santoro
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 778)


A set of anonymous processors is interconnected forming a complete synchronous network with sense of direction. Weak unison is the problem where all processors want to enter the same state (in our case “wakeup” state) in the absence of a global start-up signal. As measure of complexity of the protocols considered we use the “bits” times “lag” measure, i.e. the total number of (wakeup) messages transmitted throughout the execution of the protocol times the number of steps which are sufficient in order for all the processors to wakeup. We study tradeoffs in the complexity of such algorithms under several conditions on the behavior of the processors (oblivious, non-oblivious, balanced, etc) and provide tight upper and lower bounds on the time × messages measure.

1980 Mathematics Subject Classification


CR Categories


Key words and phrases

Anonymous network Balanced Chordalrings t-step protocol Non-oblivious Oblivious Time-message complexity Unbalanced Unison Wakeup protocol Weak unison 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Amos Israeli
    • 1
  • Evangelos Kranakis
    • 2
  • Danny Krizanc
    • 2
  • Nicola Santoro
    • 2
  1. 1.Department of Electrical EngineeringTechnionHaifaIsrael
  2. 2.School of Computer ScienceCarleton UniversityOttawaCanada

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