Energy Efficient Data Dissemination with ATIM Window and Dynamic Sink in Wireless Sensor Networks

We illustrate the effective use of ATIM (ad hoc traffic indication message) window in static sensors to obtain potential energy savings for sensors during data dissemination in wireless sensor networks. The network consists of resource-rich mobile sink node and resource-constrained sensor nodes forming a square grid. Sink may be multihop away from the sensor nodes and in order to collect the data, it moves to the vicinity of the sensor nodes in the grid. Each sensor node in the grid uses an ATIM window and sleeps during that time to conserve energy. The sleeping sensor node wakes up at regular interval of time to read the beacon messages. If the message comes from sink, sensor node immediately reads the header part of query packet to check whether it is the targeted sensor. The targeted sensor further reads the remaining part of query packet and responds back to the sink with requested data. The rest of the sensor nodes just ignore the remaining part of the query packet and go to sleep mode. If the message comes from the peer sensor node, the neighbor nodes just ignore it. We consider an affordable wireless network system with four sensor nodes and one mobile sink. Mobile sink transfers the collected data directly to the control station.