On optimal placement of relay nodes for reliable connectivity in wireless sensor networks

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Original languageEnglish
Pages (from-to)249-260
Journal / PublicationJournal of Combinatorial Optimization
Issue number2
Publication statusPublished - Mar 2006


The paper addresses the relay node placement problem in two-tiered wireless sensor networks. Given a set of sensor nodes in Euclidean plane, our objective is to place minimum number of relay nodes to forward data packets from sensor nodes to the sink, such that: 1) the network is connected, 2) the network is 2-connected. For case one, we propose a (6 + ε)-approximation algorithm for any ε > 0 with polynomial running time when ε is fixed. For case two, we propose two approximation algorithms with (24 + ε) and (6/T + 12 + ε), respectively, where T is the ratio of the number of relay nodes placed in case one to the number of sensors. We further extend the results to the cases where communication radiuses of sensor nodes and relay nodes are different from each other. © Springer Science + Business Media, LLC 2006.

Research Area(s)

  • Approximation algorithms, Fault-tolerant, Relay node placement, Sensor networks