Redundancy-Aware Topology Management in Wireless Sensor Networks

Extending the lifetime of wireless sensor networks remains the most challenging and demanding requirement that impedes large-scale deployments. Studies show that considerable energy saving can be achieved only by putting a node's radio into full sleep mode. In this paper we present RAT, which is a redundancy-aware topology management protocol. RAT selects a minimum set of active nodes that are good enough to maintain connectivity, and allows others to sleep and save energy. RAT is designed and implemented with underlying wireless channel irregularity in mind. Scalability and low overhead are the other primary design goals of RAT as well. We implement RAT in the context of Score, which is a cross-layer framework that provides RAT with the neighbor set and allows RAT to coordinate its SLEEP and ACTIVE state changes with the routing layer smoothly. Using TinyOS and PowerTOSSIM, we implement RAT on top of Score. Comparing with the all-active scenario, RAT simulation results show a total energy consumption decrease of 67% in a one-to-many routing scenario and up to 87% in a many-to-one routing scenario