# Moving Ad Hoc Networks--A Comparative Study
## 6 Comparison of MANET, VANET, FANET, and SANET (MVFS)  
Ad hoc networks are also called infrastructure-less networks, non-centered networks, multi-hop networks, and self-organizing wireless networks [78]. There is no fixed infrastructure, and each node is a vehicle/mobile/aircraft/ship which can dynamically maintain contact with other nodes in any way. Due to the limitation of the terminal's wireless coverage range, two user terminals that cannot communicate directly can use other nodes to forward packets. Any node is a router, and it can complete the function of maintaining and discovering routes to other nodes. An ad hoc wireless network consists of an independent group of wireless nodes or stations that cooperate. This network is independent of fixed infrastructure and adopts distributed management. It is a self-managed, self-organized, and self-created network. Compared with the traditional cellular network, the ad hoc wireless network does not \begin{table}
\begin{tabular}{c c c} \hline \hline
**System** & **Advantage** & **Disadvantage** \\ \hline \multirow{2}{*}{\begin{tabular}{c} Maritime wireless \\ communications \\ \end{tabular} } & MF/HF, Medium/long distance, & \multirow{2}{*}{Narrow band access, low stability} \\  & & free of charge & \\  & VHF, Visual range, free of charge & \\ \hline \multirow{2}{*}{\
\begin{tabular}{c} Marine satellite \\ communications \\ \end{tabular} } & Wide area coverage, & \multirow{2}{*}{High cost of equipment, \multirow{2}{*}{} \\  & broadband access & high monthly fee \\ \hline \multirow{2}{*}{
\begin{tabular}{c} Shore-based mobile \\ communications \\ \end{tabular} } & \multirow{2}{*}{Broadband access} & Near shore coverage, charging by \\  & & service time and amount of data \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Marine communications system performance comparison. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Reference** & **Major Contribution** & **Year** \\ \hline \multirow{4}{*}{[70]} & Survey of the existing research on underwater Marine communications, reliability & \multirow{2}{*}{2019} \\  & guarantee, classified as the four topics of channel modeling, range extension, & \\  & and capacity enhancement in SANET & \\ \hline \multirow{4}{*}{[71]} & The survey paper summarizes the underwater routing protocols proposed in recent & \multirow{2}{*}{2021} \\  & years, the performance of different underwater routing protocols, and research & \\  & challenges in SANET & \\ \hline \multirow{4}{*}{[72]} & A survey on interoperability, simplicity, and scalability for maritime services and & \multirow{2}{*}{2020} \\  & IoT applications in SANET & \\ \hline \multirow{4}{*}{SANET} & Unmanned survey systems that consist of autonomous underwater vehicles, & \multirow{2}{*}{2019} \\  & transporting AUVs roles between a survey site and shore base, and communication & \\  & relaying between ground-based mission control and the AUVs. & \\ \hline \multirow{4}{*}{[74]} & comprehensive overview of edge detection based on recent marine horizon line & \multirow{2}{*}{2020} \\  & detection, and challenging problem in SANET & \\ \hline \multirow{2}{*}{[75]} & A survey on marine vehicles with the guidance and control & \multirow{2}{*}{2021} \\  & methodologies in SANET & \\ \hline \multirow{4}{*}{[76]} & Review in most used technologies for underwater networking, a trade-off between & \multirow{2}{*}{2019} \\  & underwater properties, wireless communication technologies, and communication & \\  & quality in SANET. & \\ \hline \multirow{2}{*}{[77]} & A Survey on Underwater Wireless Sensor Networks: Requirements, Taxonomy, & \multirow{2}{*}{2020} \\  & Recent Advances, and Open Research Challenges in SAMET & \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Summary of the existing surveys on SANET. contain a base station; all the nodes operate in a distributed manner and have the function of a router which is responsible for maintaining and discovering routes to other devices/nodes and transmitting or forwarding packets to neighboring nodes.