A Randomized Algorithm for Two Servers on the Line (Extended Abstract)

@inproceedings{Bartal1998ARA,
  title={A Randomized Algorithm for Two Servers on the Line (Extended Abstract)},
  author={Yair Bartal and Marek Chrobak and Lawrence L. Larmore},
  booktitle={ESA},
  year={1998}
}
In the k-server problem we wish to minimize, in an online fashion, the movement cost of k servers in response to a sequence of requests. For 2 servers, it is known that the optimal deterministic algorithm has competitive ratio 2, and it has been a long-standing open problem whether it is possible to improve this ratio using randomization. We give a positive answer to this problem when the underlying metric space is a real line, by providing a randomized online algorithm for this case with… 
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