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Chapter 16 Modeling Data Gathering in Wireless Sensor Networks
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Fig. 4. Performance of Clustering.
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Bhaskar Krishnamachari
In this scenario, each node that senses a unique event (e.g. ???there is a bird
at location (x,y)???) not only stores this information at its own location, but
also creates additional replicas of this information and sends it to k ??’1 other
(randomly selected) locations in the network for a total of k replicas of the
information. In this problem, we assume that any random node (not just a
single pre-identified sink) can be the source of a query for this information,
so that there is no incentive to store the replicas in any particular locations.
To simplify the analysis we will focus on a simple grid network where each
node can communicate with its four cardinal neighbors. A more sophisticated
version of the analysis described here, considering expanding ring searches
for a randomly deployed network, is presented in [4]. In the simple grid network,
we assume that each query proceeds sequentially in a pre-determined
trajectory that (if a solution is not obtained) eventually visits all nodes in the
network.
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