# Deployment Strategy of Shore-Based Cooperative Units for the Internet of Inland Vessels
## 2 Ship-Shore Communication Needs of Internet of Inland Vessels  
### System Architecture and Operating Mode of the Internet of Inland Vessels  
The Internet of Inland Vessels aims to achieve efficient collaboration between ships, shore facilities, and related management departments. The system realizes real-time information sharing among ships, ports, docks, and other shore infrastructure through information technology, communication technology, and computing technology. Figure 1 shows the system architecture of the Internet of Inland Vessels. The information support of shore-based collaborative units in the Internet of Inland Vessels includes basic information about the navigable environment and related information (e.g., shore-based perception, remote decision-making, and remote control for intelligent ships). Basic navigational environment information includes the types of navigable water areas, meteorological and hydrological conditions, regional traffic flow status, maritime management information, ports and terminals, and other berthing information. Shore-based perception information includes shore-based video, radar, smart bayonet and other perceived water target information, shore-based infrastructure status information, etc. Remote decision-making and remote control instructions come from remote control stations and serve the remote control and autonomous navigation of intelligent ships. For the business layer, the randomness of ship-shore communication services is large, and the number of services generated in the system has a greater correlation with the arrival process of the ship. Ship traffic flow, business types, and businesses generated in a single ship are synthesized to represent the arrival process model of businesses in the system. The characteristics of ship traffic flow are described through the traffic flow density. Assuming that the density of ships is \(\rho\) ship/km in a certain section of a channel with a length of \(S\) km, \(n_{s}=S\cdot\rho\) is the number of ships in that section of the channel. For each ship, the OFF/ON model is used to describe the arrival characteristics of various services; the ON/OFF state duration of some services is described by exponential distribution. The arrival time and duration of each business are as follows: the start time of the ON stage is the arrival time of a certain business, and the duration of the ON stage is that of the business. The data layer is analyzed by selecting some services in traffic safety, traffic efficiency, and information services. Combined with the ship's intelligent navigation specifications, data packet rules are defined for each business (Table 1 for details). \begin{table}
\begin{tabular}{c c c} \hline \hline
**Business Type** & **Business Name** & **Communication Method** \\ \hline \multirow{3}{*}{Traffic safety} & Navigation safety warning & Upstream and downstream \\ \cline{2-3}  & Reconstruction of sailing scenes & Upstream \\ \cline{2-3}  & Remote driving command verification & Upstream and downstream \\ \hline \multirow{3}{*}{Traffic efficiency} & Route planning & Downstream \\ \cline{2-3}  & Speed optimization & Downstream \\ \hline \multirow{3}{*}{Information service} & Traffic flow status broadcast & Downstream \\ \cline{2-3}  & Perception enhancement & Downstream \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Business types and names. Figure 2: Three-layer business model. In the transport layer, according to different communication methods, we can choose to use the TCP/IP protocol, DDS protocol, and MQTT protocol to encapsulate and transmit data. Lappl bytes is the amount of data in the application layer of the shipping service per unit time; \(\eta\) is the effective data rate of the system. The amount of data is as follows after encapsulation. \[L_{DLL}=\frac{L_{appl}}{\eta} \tag{1}\]  
Signaling refers to messages or instructions used to control and manage a communication system in wireless communication.