Rendezvous of Mobile Agents in Directed Graphs

  • Jérémie Chalopin
  • Shantanu Das
  • Peter Widmayer
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6343)


We study the problem of gathering at the same location two mobile agents that are dispersed in an unknown and unlabeled environment. This problem called Rendezvous, is a fundamental task in distributed coordination among autonomous entities. Most previous studies on the subject model the environment as an undirected graph and the solution techniques rely heavily on the fact that an agent can backtrack on any edge it traverses. However, such an assumption may not hold for certain scenarios, for instance a road network containing one-way streets. Thus, we consider the case of strongly connected directed graphs and present the first deterministic solution for rendezvous of two anonymous (identical) agents moving in such a digraph. Our algorithm achieves rendezvous with detection for any solvable instance of the problem, without any prior knowledge about the digraph, not even its size.


Distributed Algorithm Directed Graph Leader Election Rendezvous Anonymous Networks Mobile Agents Graph Exploration 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Jérémie Chalopin
    • 1
  • Shantanu Das
    • 1
  • Peter Widmayer
    • 2
  1. 1.LIFCNRS & Aix-Marseille UniversityFrance
  2. 2.Institute of Theoretical Computer ScienceETH ZürichSwitzerland

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