Synchronous sleep andwake in IP-enabled wireless sensor networks

Energy efficiency in wireless sensor networks is one of the most crucial technologies. In this paper, we propose a simple and feasible synchronous sleep and wake mechanisms for wireless sensor networks in a small scale. Sensor nodes are divided into forwarding nodes and listening nodes. Beacon frame containing sleep command from coordinator can be forwarded to listening nodes by forwarding nodes. The network can enter sleep at about the same time. Through such network synchronization mechanisms, we can realize synchronous sleep and wake of the entire network. The proposed mechanisms are implemented in sensor nodes and are evaluated in a test-bed. Through the analysis and evaluation of experimental data, it confirms the proposed energy-saving mechanisms are feasible and effective.