Optimal Locations for Join Processing in Sensor Networks

Cost based in-network join strategy in tree routing sensor networks

“…But, the cost models used in these methods are not accurate since they did not consider join selectivities and they assume that all sensor readings in a query region are collected at the center of the region. A similar work is done in [20], in this work, as the optimal join location, the weighted Fermat point is obtained. Coman et al [6] presented three join plans which are similar to our three basic join plans.…”

“…Some in-network join methods between two regions in sensor networks were presented in [6,17,20]. [17] considers the optimal join location using the cost model.…”

“…Mediated join [6] is similar to our coverJoin since two relation is joined at a node. Like [20] the weighted Fermat point is considered as the join location in mediate join. But, since our work is based on tree routing, the join location of coverJoin is cov min (Q L S Q R ).…”

“…However, due to the hierarchical structure of sensor networks, traditional techniques are not directly applicable. Thus, recently, research on in-network join processing [17,[20][21][22][23] has been proposed to reduce the communication overhead. In in-network join processing, a node generates join results.…”