Data Freshness Based AUV Path Planning for UWSN in the Internet of Underwater Things

In Underwater Wireless Sensor Networks (UWSN), Autonomous Underwater Vehicles (AUVs), which are responsible to collect(deliver) data from(to) sensors, bridge the network to the rest of the world-wide network to form the Internet of Underwater Things (IoUT). In IoUT acoustic sensors that cause long propagation delay together with slow AUV speed could render the collected data useless if not delivered to the sink in timely manner. In addition, in security, environment monitoring, and emergency applications the age of the data cached by the AUV is very crucial. In this paper, we harnessed the end-to-end data freshness constraint to design AUV path of traversal. The resultant dynamic path of traversal improves the overall data freshness of the sectors of UWSN. In the evaluation, compared to the conventional lawnmower and shortest path traversal algorithms, the proposed scheme improved the overall data freshness at the cost of data collection delay.