# A Polylogarithmic-Competitive Algorithm for the k-Server Problem

```@article{Bansal2011APA,
title={A Polylogarithmic-Competitive Algorithm for the k-Server Problem},
author={Nikhil Bansal and Niv Buchbinder and Aleksander Madry and Joseph Naor},
journal={2011 IEEE 52nd Annual Symposium on Foundations of Computer Science},
year={2011},
pages={267-276}
}```
• Published 7 October 2011
• Computer Science, Mathematics
• 2011 IEEE 52nd Annual Symposium on Foundations of Computer Science
We give the first polylogarithmic-competitive randomized algorithm for the k-server problem on an arbitrary finite metric space. In particular, our algorithm achieves a competitive ratio of Õ(log3 n log2 k) for any metric space on n points. This improves upon the (2k-1)-competitive algorithm of Koutsoupias and Papadimitriou (J. ACM 1995) whenever n is sub-exponential in k.
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