Replica Placement on Bounded Treewidth Graphs
نویسندگان
چکیده
We consider the replica placement problem: given a graph with clients and nodes, place replicas on a minimum set of nodes to serve all the clients; each client is associated with a request and maximum distance that it can travel to get served and there is a maximum limit (capacity) on the amount of request a replica can serve. The problem falls under the general framework of capacitated set covering. It admits an O(log n)approximation and it is NP-hard to approximate within a factor of o(log n). We study the problem in terms of the treewidth t of the graph and present anO(t)-approximation algorithm.
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