On Multicasting in Underwater Acoustic Networks

Even though underwater acoustic communication suffers from long propagation delays and has very limited bandwidth, it still plays a key role in supporting long-distance, low-power communication in underwater sensor networks. Many previous studies have tried to mitigate the impact of long propagation delays, but recently, the focus has shifted from mitigating to exploiting large propagation delays. In this paper, we consider an underwater acoustic network which employs a time- division based scheduling strategy and supports multicasting, meaning that packets may have multiple destinations. In this context, we establish an upper bound on the throughput of a general multicasting network, and study networks which can achieve this bound. We also study the throughput of ring networks (in which nodes are uniformly located on a circle) and give some examples and schedules which achieve the maximum possible throughput. Finally, we explore the properties of valid, perfect, and fair slot schedules for ring networks.