On the Handling Node Failure: Energy-Efficient Job Allocation Algorithm for Real-Time Sensor Networks

Guaranteeing quality of real-time services in wireless sensor networks (WSN) requires efficient resource management, especially for energy resources. This is due to the fact that nodes in such networks usually use limited non-replaceable batteries. On the other hand, the nodes of WSNs often work in harsh environments, and therefore, susceptible to failure occurrences due to environmental affects or exhaustion of their battery. In this paper, we present a dynamic energy efficient real-time job allocation algorithm called ERTJA for handling node failures in a cluster. ERTJA tries to minimize the energy consumption of the cluster by minimum activation of sleeping nodes while guaranteeing the QoS of the application assigned to the cluster at the same previous level. Further, when the number of sleeping nodes is limited, the proposed algorithm uses the idle times of active nodes to have a graceful QoS degradation of the cluster upon node failure. Simulation results show significant performance improvements of ERTJA in terms of energy consumption comparing to the N-EDF-Plus algorithm. According to the results, ERTJA can save up to 26.5% of the cluster´s energy consumption with respect to N-EDF-Plus in the studied scenarios.