# Resistance to Cybersecurity Attacks in a Novel Network for Autonomous Vehicles
## 2 Related Work
### Next Generation Networks  
The nodes within a mobile ad hoc network (MANET) can be many different mobile devices, all connected via Bluetooth and/or a WiFi to form a dynamic network. The recent release of widespread 5G networking capabilities has led to more research on the topic as they are able to support a much larger flow of traffic [2]. A key feature is mobility and allowing the nodes to move freely. Due to the high expense most of the research and experimentation into MANETs is only achievable within computer simulations [3]. MANETs allow communications directly between two nodes rather than having a router between them. They have routing protocols embedded within them in order to allow nodes to communicate in a predefined, consistent manner. Now that mobile phones are becoming more capable (such as incorporating 5G [4]), the networks are becoming much more feasible as the nodes have more capability to perform processes traditionally managed by a fixed infrastructure.  
The networks have the potential to save lives as well as generally improve vehicle and road safety [5]. If the networks were widely adopted, the convenience and comfort of passengers and drivers might also be improved. In vehicular ad hoc networks (VANETs), mobility is especially important as not only do most vehicles travel long distances, but they also move at relatively high speeds [6]. VANETs can include multiple types of vehicle and can adapt quickly to real world movements. They also allow vehicles to communicate with road-side equipment: a fixed infrastructure alongside of the road so that the drivers of vehicles can be alerted to information and services. This could include safety and traffic information as well as any services that the driver may need at that given point in time [7].  
Flying ad aoc networks (FANETs) are another common form of complex next-generation network. They consist of a number of UAVs that communicate directly with each other, allowing the data to remain more secure than when communicating using infrastructure such as a group base or satellite [8]. Having a network of UAVs able to work together to achieve a high-level goal would allow military operations to be completed quicker and more reliably as it introduces some fault tolerance over a single drone [9]. The use of drones and FANETs can also be combined with other networks such as a VANET in order to create a complex network of networks. This would allow a drone to communicate with a vehicle on the ground using a hop-based approach [10]. This could be used in a smart city scenario where, for example, drones are used to pass data directly to police officers on the ground.  
Delay-tolerant networks (DTNs) are useful where reliable communication is not available for message transmission, due to a sparse and intermittent connection. End-to-end connectivity is not guaranteed in a DTN and therefore alternate routing protocols such as the store-and-forward approach increase the probability that a message will be delivered once a connection has been reinstated [11]. They have been developed in order to overcome technical issues that have been identified in standard networking topologies. When operating in either mobile or extremely sparse environments DTNs used as constant connections are a rare occurrence [12].  
Opportunistic networks are viewed as a subclass of DTNs where communication is intermittent. This means that an end-to-end path between destination and source may never exist. Nodes are only connected temporarily, and the topology is highly changeable [13]. One-hop communication is very important in an opportunistic network. This is a wireless and short-range message exchange between nodes with no intermediate node on the communication path, meaning that there is no message-routing. The nodes are able to send and receive arbitrary data to and from any node that they are in direct communication range with [14].