Linear Rendezvous with Asymmetric Clocks

Authors Jurek Czyzowicz, Ryan Killick, Evangelos Kranakis



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Jurek Czyzowicz
  • Département d'informatique, Université du Québec en Outaouais, Gatineau, Canada
Ryan Killick
  • School of Computer Science, Carleton University, Ottawa, Canada
Evangelos Kranakis
  • School of Computer Science, Carleton University, Ottawa, Canada

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Jurek Czyzowicz, Ryan Killick, and Evangelos Kranakis. Linear Rendezvous with Asymmetric Clocks. In 22nd International Conference on Principles of Distributed Systems (OPODIS 2018). Leibniz International Proceedings in Informatics (LIPIcs), Volume 125, pp. 25:1-25:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2019)
https://doi.org/10.4230/LIPIcs.OPODIS.2018.25

Abstract

Two anonymous robots placed at different positions on an infinite line need to rendezvous. Each robot possesses a clock which it uses to time its movement. However, the robot's individual parameters in the form of their walking speed and time unit may or may not be the same for both robots. We study the feasibility of rendezvous in different scenarios, in which some subsets of these parameters are not the same. As the robots are anonymous, they execute the same algorithm and when both parameters are identical the rendezvous is infeasible. We propose a universal algorithm, such that the robots are assured of meeting in finite time, in any case when at least one of the parameters is not equal for both robots.

Subject Classification

ACM Subject Classification
  • Theory of computation → Design and analysis of algorithms
  • Theory of computation → Distributed algorithms
Keywords
  • anonymous
  • asymmetric clock
  • infinite line
  • rendezvous
  • mobile robot
  • speed
  • competitive ratio

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