NoSE: Efficient Maintenance and Initialization of Wireless Sensor Networks

Wireless sensor networks (WSNs) are used for longterm observation and monitoring. Such long-lasting deployments require different maintenance tasks, such as the replacement of nodes and the most critical initial installation of the sensor nodes. During maintenance, the actual node placement is modified resulting in temporary topology fluctuations, which are very expensive in terms of energy. We propose the NoSE protocol stack enhancement for WSNs to target maintenance tasks. NoSE provides the functionality for switching the network between an operational state and a deep sleep state. The deep sleep state allows for switching the network to energy savings, while performing maintenance. The network may be woken up at any given time. During the time bounded start-up, a comprehensive neighborhood assessment provides a solid basis for the subsequent network topology setup. Thus the success of a maintenance task, e.g., the initial deployment of the nodes, can be instantly validated. We present NoSE on a case study focusing on the initialization of a fire-detector WSN validated on a testbed and in simulation.