A Medium Access Control Protocol Based on Parity Group-Graph Coloring for Underwater AUV-Aided Data Collection.

Data collection and transmission is the foundation for Internet of Underwater Things (IoUT) applications. Currently, quite a few Autonomous Underwater Vehicle (AUV)-assisted data collection technologies have been proposed. Most of them concentrate on AUV path planning or multi-path routing for data transmission, although MAC protocol design is crucial for reliable and secure data transmission in IoUT; hence, a MAC protocol based on Parity Group-Graph Coloring (PGGC-MAC) is investigated for underwater AUV-aided data collection. First, the AUV broadcasts path packets before data collection, informing sensor nodes of the path to travel in advance. Then, sensor nodes perform location update before AUV arrives, and collect the location information of neighbor nodes. Based on the position and the path information, the dynamic network topology is analyzed and the interference graph is obtained, which is used to assign working time slots for sensor nodes to transmit packets to the AUV. Finally, simulation results demonstrate that PGGC-MAC outperforms other related techniques in terms of network throughput, packet delivery ratio, and energy usage, etc.