# Moving Ad Hoc Networks--A Comparative Study
## 6 Comparison of MANET, VANET, FANET, and SANET (MVFS)
The topological architecture of ad hoc wireless networks can be divided into two classes: flat peer-to-peer and layered architecture. In peer-to-peer architecture, all the network nodes are in the same state. In the hierarchical structure of an ad hoc wireless network topology, the entire network consists of groups as subnets. Each group consists of multiple cluster members and group heads. The group leaders can form higher-level networks, and higher-level networks can be grouped to create higher-level networks. The members and groups of each group change dynamically and are automatically networked. Depending on the different hardware configurations, a layered structure can be divided into single-frequency and multi-frequency layered structures. The single frequency hierarchy uses one frequency for communication, and all the nodes use the same frequency. In multi-layer frequency architecture, in the case of a two-layer network, the communication range of the lower layer network becomes narrower, and the communication range of the upper layer network becomes wider. The cluster members use the communication frequency. The head node uses one frequency to communicate with the block members and the other frequency to maintain the connection to the cluster head. There are advantages and disadvantages to using a generic point-to-point structure and hierarchy. In the network structure of the general simple point-to-point structure, the state of each node is the same, and if there are multiple paths, it is the source node. The target node and communications network are not a bottleneck, but the network security is relatively high in comparison, and the biggest drawback is that the network size is limited. As the network grows, the cost of maintaining a route increases dramatically and the bandwidth consumed becomes limited. The hierarchical network size is unlimited, scalability is good, and the burden of group routing is relatively small. The hierarchical structure requires a complex algorithm for the block header selection, but hierarchical network architecture has high system throughput and easy node placement. Currently, self-organizing wireless networks are gradually showing a hierarchical trend. Several network routing algorithms have been proposed according to the hierarchical network model. Compared with cellular networks, wireless ad hoc networks have incomparable advantages. First, no fixed infrastructure (such as base stations) is required. Wireless ad hoc networks can be established anytime and anywhere, and can be used when there are no other communication facilities, or when some facilities cannot be used due to confidentiality, cost, or security, etc. Secondly, the ad hoc network is not restricted by a fixed topology structure, and it has strong fault tolerance and robustness. Wireless ad hoc networks have broad application prospects. Military operations and rescue operations in earthquakes, floods, or remote areas are traditional application areas of ad hoc networks. However, they can also be used as a wireless access network, providing rapid networking capabilities. In the local area, notebooks and palmtop computers can use ad hoc methods to publish and share information in meetings. The personal area network using Bluetooth technology is very promising as a short-distance ad hoc network. Sensor networks can be used in many fields, such as battlefield intelligence collection, environmental pollution monitoring, the early prediction of earthquakes and tsunamis, and production workshop monitoring. Ad hoc networks include MANET, VANET, FANET, and SANET (Figure 1). In MANET, each node acts as a host and as a router, where the nodes are linked through wireless channels in the network. The nodes communicate without relying on any pre-existing infrastructure. VANET is a subset of MANETs, and FANET is a subset of VANET. SANET is one of the popular types of ad hoc networks. Table 9 summarizes the differences between traditional ad hoc wireless networks.