Practical Steps towards Establishing an Underwater Acoustic Network in the Context of the Marine Internet of Things  
[PERSON]  
Research Laboratory of Robotics and Intelligent Control Systems, Svensatopol State University,  
Sevastopol 299053, Russia; [EMAIL_ADDRESS] (K.K. ); [EMAIL_ADDRESS] (A.K. ); [EMAIL_ADDRESS] (O.K. ); [EMAIL_ADDRESS] (M.D. ); [EMAIL_ADDRESS] (T.A.) Independent Researcher, Sevastopol 299006, Russia; [EMAIL_ADDRESS]  
[PERSON]  
Research Laboratory of Robotics and Intelligent Control Systems, Svensatopol State University,  
Sevastopol 299053, Russia; [EMAIL_ADDRESS] (K.K. ); [EMAIL_ADDRESS] (A.K. ); [EMAIL_ADDRESS] (O.K. ); [EMAIL_ADDRESS] (M.D. ); [EMAIL_ADDRESS] (T.A.) Independent Researcher, Sevastopol 299006, Russia; [EMAIL_ADDRESS]  
[PERSON]  
Research Laboratory of Robotics and Intelligent Control Systems, Svensatopol State University,  
Sevastopol 299053, Russia; [EMAIL_ADDRESS] (K.K. ); [EMAIL_ADDRESS] (A.K. ); [EMAIL_ADDRESS] (O.K. ); [EMAIL_ADDRESS] (M.D. ); [EMAIL_ADDRESS] (T.A.) Independent Researcher, Sevastopol 299006, Russia; [EMAIL_ADDRESS]  
[PERSON]  
Department of Computer Science, University of Toronto  
underwater environment due to its ability to transmit over long distances, ranging from several hundred meters to tens of kilometers [1; 7; 8; 9]. However, it does come with several limitations, such as low bandwidth, high intensity, long-duration reverberation, relatively large Doppler spectrum expansion, etc. [10; 11]. The process of addressing data transmission challenges via the hydroacoustic channel entails integrating hydroacoustic modems into the sensor modules of underwater devices [12]. Typically, underwater acoustic modems are most effective when dealing with a limited number of asynchronously interacting data sources or recipients. When multiple acoustic modems operate simultaneously within an overlapping area, collisions of data packets received from various sources can occur. These collisions result in the loss of some or all information. As the number of concurrently operating hydroacoustic modems increases, the stability of data transmission provided by physical layer algorithms diminishes, and the probability of collisions rises. Consequently, the effective operation of modems becomes compromised, and in some cases, even unfeasible. In the context of airspace, numerous methods exist for routing and resolving data collisions [13]. However, in hydroacoustics, these methods may not always be employed and are typically subjected to significant limitations. To ensure effective operation in a hydroacoustic signal propagation environment and to minimize or eliminate collisions during data exchange and delivery between two modems that lack synchronous operation capability, as well as to reduce access time to the signal propagation environment, methods from the media access control layer that utilize data link layer protocols are necessary. Typically, this problem is addressed by employing code division or frequency division across hydroacoustic channels, i.e., when modems operate at distinct frequencies, ensuring non-interference. This enables underwater network subscribers to communicate either in a \"point-to-point\" (P2P) format or in \"multicast\" mode, where each communication occurs independently. However, if network-wide transmission is required, this approach becomes unsuitable, as network transmission relies on \"broadcast\" messages and some network nodes, particularly data source and data sink, which can stay too far from each other, outside of their mutual audibility (operation ranges). For transmitting data in a hydroacoustic network with constantly changing conditions of emission and reception of signals, specialized network protocols have recently been developed. These protocols can consider and utilize a dynamically varying number of network nodes situated in the region of mutual audibility or (due to the asymmetry of communication channel characteristics) one-way audibility.