Page 2 Lecture Notes in Computer Science 2865 Edited by G. Goos ...

IDEA: An Iterative-Deepening Algorithmfor Energy-Efficient Queryingin Ad Hoc Sensor NetworksSwapnil PatilDepartment of Computer ScienceState University of New York at Stony BrookStony Brook, NY 11790, USAswapnil@cs.sunysb.eduAbstract. The data-centric ad hoc sensor networks make efficientsearching a crucial and challenging operation. Dynamic topology makeflooding the most widely adopted solution at a cost of high bandwidthcongestion leading to inefficient use of resources and low network lifetime.This paper presents IDEA, an efficient querying and searching techniquefor ad hoc sensor networks that reduces average energy consumptionwhile maintaining the capacity and performance of the network. IDEAis based on iterative-deepening search which check-points the flooding ofrequests based on the results. This is further extended to a token-basedapproach called T-IDEA, which involves local decisions made by nodesto determine their participation in a virtual searching network. Resultsshow that IDEA and T-IDEA significantly reduces the energy consumptioncompared to classical flooding approaches. Apart from that T-IDEApresents a highly distributed self-supervising topology formation whichperforms very well to increase the lifetime of the ad hoc sensor network....1 IntroductionRecent advances in wireless and mobile networks have led to interest in buildingand deploying in ad-hoc and sensor networks. Due to their constrained environmentand distributed operations, these networks provide an challenging researchproblems. Due to the distributed operations, most routing and searchingoperations in mobile ad-hoc and sensor networks are multi-hop. Thus, makingflooding based approaches the most feasible. Many routing protocols [1,2,3] havebeen proposed using flooding or broadcast mechanisms.In flooding, each node broadcasts the query to all its neighboring nodes.These nodes perform a local search for the query. If unsuccessful, these nodesbroadcast the query to its neighbors and so on. Thus the query reaches theentire network, more than once for most of the nodes. But each node rejectsquery messages which have already been received once (based on their ID).This paper introduces and evaluates new searching algorithm(s) in ad hocsensor networks called IDEA and T-IDEA. These techniques achieve a significantgain over classical flooding based approach, and could easily scale to largenetworks.S. Pierre, M. Barbeau, and E. Kranakis (Eds.): ADHOC-NOW 2003, LNCS 2865, pp. 199–210, 2003.c○ Springer-Verlag Berlin Heidelberg 2003