Sink mobility for commutative cipher based en-route filtering to prolong the network lifetime in wireless sensor networks

Wireless sensor networks (WSNs) are comprised of a large number of randomly deployed low-cost, small-size, low-energy un-attended sensor nodes. An adversary can inject a large quantities of fabricated reports towards sink(s) draining scarce energy en-route. En-route filtering schemes such as commutative cipher based en-route filtering (CCEF) are proposed to counter these attacks and hence save energy. While these schemes saves energy they may not necessarily prolong network lifetime. In CCEF, inherent limitations such as; 1) fixed paths, 2) energy inefficient routing, and 3) unbalanced communication loads leads to adverse effects on network lifetime. In order to counter these issues, we propose sink mobility based CCEF (SM_CCEF). Energy-aware routing and sink mobility help avoiding energy-hole problem which is observed in static sink based networks. Experimental results demonstrate the efficacy of our proposed method which prolonged network over three folds because of balanced communication loads over larger groups of sensor nodes.