Online k-Server Routing Problems

  • Vincenzo Bonifaci
  • Leen Stougie
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4368)


In an online k-server routing problem, a crew of k servers has to visit points in a metric space as they arrive in real time. Possible objective functions include minimizing the makespan (k-Traveling Salesman Problem) and minimizing the average completion time (k-Traveling Repairman Problem). We give competitive algorithms, resource augmentation results and lower bounds for k-server routing problems on several classes of metric spaces. Surprisingly, in some cases the competitive ratio is dramatically better than that of the corresponding single server problem. Namely, we give a 1+O((logk)/k)-competitive algorithm for the k-Traveling Salesman Problem and the k-Traveling Repairman Problem when the underlying metric space is the real line. We also prove that similar results cannot hold for the Euclidean plane.


Completion Time Release Date Competitive Ratio Online Algorithm Single Server 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Vincenzo Bonifaci
    • 1
    • 2
  • Leen Stougie
    • 1
    • 3
  1. 1.Department of Mathematics and Computer ScienceEindhoven University of TechnologyEindhovenThe Netherlands
  2. 2.Department of Computer and Systems ScienceUniversity of Rome “La Sapienza”RomaItaly
  3. 3.CWIAmsterdamThe Netherlands

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