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Coding-based Storage Design for Continuous Data Collection in Wireless Sensor Networks
Cheng Zhan,Fuyuan Xiao 한국통신학회 2016 Journal of communications and networks Vol.18 No.3
In-network storage is an effective technique for avoidingnetwork congestion and reducing power consumption in continuousdata collection in wireless sensor networks. In recent years,network coding based storage design has been proposed as a meansto achieving ubiquitous access that permits any query to be satisfiedby a few random (nearby) storage nodes. To maintain dataconsistency in continuous data collection applications, the readingsof a sensor over time must be sent to the same set of storagenodes. In this paper, we present an efficient approach to updatingdata at storage nodes to maintain data consistency at thestorage nodes without decoding out the old data and re-encodingwith new data. We studied a transmission strategy that identifiesa set of storage nodes for each source sensor that minimizes thetransmission cost and achieves ubiquitous access by transmittingsparsely using the sparse matrix theory. We demonstrate that theproblem of minimizing the cost of transmission with coding is NPhard. We present an approximation algorithm based on regardingevery storage node with memory size B as B tiny nodes that canstore only one packet. We analyzed the approximation ratio of theproposed approximation solution, and compared the performanceof the proposed coding approach with other coding schemes presentedin the literature. The simulation results confirm that signifi-cant performance improvement can be achieved with the proposedtransmission strategy.