Randomized Rendez-Vous with Limited Memory

  • Evangelos Kranakis
  • Danny Krizanc
  • Pat Morin
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4957)


We present a tradeoff between the expected time for two identical agents to rendez-vous on a synchronous, anonymous, oriented ring and the memory requirements of the agents. In particular, we show that there exists a 2t state agent, which can achieve rendez-vous on an n node ring in expected time O( n 2/2 t  + 2 t ) and that any t/2 state agent requires expected time Ω( n 2/2 t ). As a corollary we observe that Θ(loglogn) bits of memory are necessary and sufficient to achieve rendez-vous in linear time.


Mobile Agent Edge Label Simple Random Walk Random Coin Start Vertex 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Evangelos Kranakis
    • 1
  • Danny Krizanc
    • 2
  • Pat Morin
    • 1
  1. 1.School of Computer ScienceCarleton University 
  2. 2.Department of Mathematics and Computer ScienceWesleyan University 

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