Journal of Combinatorial Optimization

, Volume 12, Issue 4, pp 327–336 | Cite as

The web proxy location problem in general tree of rings networks

  • Guangting Chen
  • Gu Zhang
  • Rainer E. Burkard


The Web proxy location problem in general networks is an NP-hard problem. In this paper, we study the problem in networks showing a general tree of rings topology. We improve the results of the tree case in literature and get an exact algorithm with time complexity O(nhk), where n is the number of nodes in the tree, h is the height of the tree (the server is in the root of the tree), and k is the number of web proxies to be placed in the net. For the case of networks with a general tree of rings topology we present an exact algorithm with O(kn 2) time complexity.


Location problem Tree General tree of rings Proxy Placement 


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Copyright information

© Springer Science + Business Media, LCC 2006

Authors and Affiliations

  1. 1.The Institute of Operational Research and CyberneticsHangzhou Dianzi UniversityHangzhouP.R. China
  2. 2.Technische Universität GrazInstitut für MathematikGrazAustria

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