# Resistance to Cybersecurity Attacks in a Novel Network for Autonomous Vehicles
## 5 Autonomous Vehicle Opportunistic Network  
In order to evaluate the effect of attacking vehicles, each node was monitored for the messages it was sending and receiving. The environment was kept constant with the only changes being the substitution of compromised cars for regular cars. The experiments were developed around Helsinki City Centre as a smart city and included varying modes of transport including trans, buses, cars and pedestrians. Each of the individuals was connected using an Opportunistic Network operating over Bluetooth.  
In the city centre the trans and buses are autonomous and rely on the messages they receive from other vehicles to get the passengers to their required destination. The messages contain important data about the current traffic in the city, the status of controlled junctions the vehicles must drive through, and the position of other individuals in the vicinity of the autonomous vehicle. The messages originate from other individuals in the network as well as roadside infrastructure such as traffic lights. The map (Figure 4) shows the public transport system within the city that the attackers will be attempting to disrupt.  
The aim of the attacking group is to prevent data arriving at the autonomous vehicles by disrupting messages in the VANET, therefore reducing the messages delivered throughout the network. This is to cause commotion within the city and make people's journeys more dangerous. All of the attacks are distributed rather than being focused on a particular target (this could be a specific vehicle or location) this is to cause the most widespread disruption to the network rather than specific localised area.  
With no data reaching the autonomous vehicles they will stop (to prevent any dangerous actions being taken), however this could be in the middle of a junction or road causing a hazard to other road users and potentially causing a roadblock. This could be used by the attackers to prevent people arriving at or leaving the city. If only some data are received by the autonomous vehicles, they would function but less reliably than if all messages were received. This in turn could cause unnecessary traffic to certain areas, as well as dangerous manoeuvrers being made. For example, if a message about an individual's proximity to an autonomous bus gets dropped by a black hole vehicle, the bus may attempt to manoeuvre into the individuals' space, causing them harm. This is of more use to attackers trying to endanger the general public due to the resulting unpredictable behaviour of the autonomous vehicles.  
Figure 3: Diagram to show vehicular nodes communicating.  
If a serious traffic jam within the city were to occur as a fault of the network, there could be major consequences. Not only would the blame be put on the technology and damage the reputation for the networks (and technological advance) as a whole, but also to the immediate areas affected. Traffic congestion and road safety (especially crash severity) are shown to have a correlation [39] and thus with congestion in an area, the public are less safe. Studies have also shown that uncontrolled traffic problems (such as the unpredicted ones in this instance) can lead to more fatalities on roads and, as such, should be avoided by any means possible [40].