Energy-efficient routing protocols for solving energy hole problem in wireless sensor networks.

Recently, researchers introduced energy-efficient dynamic routing protocols for wireless sensor networks to avoid the premature end of network lifetime. This paper addresses the routing hole problem due to energy depletion and the trade-off between the network need for periodic setups to preserve connectivity and power constraints on sensor nodes. The paper solves the problem of the premature end of network lifetime in applications where the base station (BS) is far from the Region Of Interest (ROI). Therefore, we propose two distributed, energy-efficient, and connectivity-aware routing protocols for solving the routing hole problem. These protocols are On-Hole Children Reconnection (OHCR) with local nature and On-Hole Alert (OHA) with global nature. The proposed protocols preserve the connectivity of all single setup phase, single path networks with any topology in an energy efficient manner by avoiding topology reformation overhead. The simulation results proved that the proposed protocols outperform the recent ones in terms of network lifetime, node loss rate, and network overhead. Such that, the two protocols are examined on both Degree Constrained Tree (DCT) and Shortest Path Tree (SPT) to provide about 50% to 75% increase in network lifetime over the recent energy efficient routing protocols; like UCCGRA and NEECP. Additionally, applying OHCR and OHA to any network topology doesn't affect its stability period, since these protocols are triggered by routing hole occurrence.