Vehicular ad hoc networks (VANETs) are a subgroup of mobile ad hoc networks (MANETs) with the distinguishing property that the nodes are vehicles like cars, trucks, buses and motorcycles. This implies that node movement is restricted by factors like road course, encompassing traffic and traffic regulations. Because of the restricted node movement it is a feasible assumption that the VANET will be supported by some fixed infrastructure that assists with some services and can provide access to stationary networks. The fixed infrastructure will be deployed at critical locations like slip roads, service stations, dangerous intersections or places well-known for hazardous weather conditions.
Nodes are expected to communicate by means of North American DSRC standard that employs the IEEE 802.11p standard for wireless communication. To allow communication with participants out of radio range, messages have to be forwarded by other nodes (multi-hop communication). Vehicles are not subject to the strict energy, space and computing capabilities restrictions normally adopted for MANETs. More challenging is the potentially very high speed of the nodes (up to 250 km/h) and the large dimensions of the VANET.
The primary VANET's goal is to increase road safety. To achieve this, the vehicles act as sensors and exchange warnings or – more generally – telematics information (like current speed, location or ESP activity) that enables the drivers to react early to abnormal and potentially dangerous situations like accidents, traffic jams or glaze. The information provided by other vehicles and stationary infrastructure might also be used for driver assistant systems like adaptive cruise control (ACC) or breaking assistants. In addition, authorized entities like police or firefighters should be able to send alarm signals and instructions e.g. to clear their way or stop other road users. Besides that, the VANET should increase comfort by means of value-added services like location based services or Internet on the road.
VANET security
These applications imply different security and privacy requirements with respect to the protection goals integrity, confidentiality and availability. Nevertheless, there is a common need for a security infrastructure establishing mutual trust and enabling cryptography. Simply using digital signatures and a public key infrastructure (PKI) to protect message integrity is insufficient taking into account multilateral security and performance requirements.
Therefore we developed a security architecture for VANETs that balances security requirements of all participants while keeping in mind the realtime requirements. We also identified and – if necessary – developed feasible mechanisms that fit in this architecture. Currently, we evaluate the architecture and mechanisms in simulations. For more information see publications.
Security architecture overview
VANET simulator
VANETs are still in conceptual design so experimental analysis of the designed mechanisms is not possible today. Therefore, we are creating a VANET simulator to fill that gap since available simulation tools didn't meet our requirements.
Our simulator may be used to create own maps to generate specific traffic situations or import areas of the OpenStreetMap-Project for a more realistic road system. The Scenario contains vehicles equipped with wifi components and different characteristics that are created randomly or manually. Events like blocked roads or lanes may be triggered. Furthermore, security techniques like pseudonym changes or mix zones (see Scheuer, Plößl, Federrath: Preventing Profile Generation in Vehicular Networks) are implemented. The simulation itself is fully deterministic and therefore completely reproducible at any time.
Screenshots
Simulation of 50k vehicles at Regensburg
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Zoomed view of the "Lappersdorfer Kreisel"
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Creation of own road systems
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Definition of Events
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 Random creation of vehicles
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 Analysis tools
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Publications
See the list of publications