Intervehicular communication (IVC) is an important emerging research area that is expected to considerably contribute to traffic safety and efficiency. In this context, many possible IVC applications share the common need for fast multihop message propagation, including information such as position, direction, and speed. However, it is crucial for such a data exchange system to be resilient to security attacks. Conversely, a malicious vehicle might inject incorrect information into the intervehicle wireless links, leading to life and money losses or to any other sort of adversarial selfishness (e.g., traffic redirection for the adversarial benefit). In this paper, we analyze attacks to the state-of-the-art IVC-based safety applications. Furthermore, this analysis leads us to design a fast and secure multihop broadcast algorithm for vehicular communication, which is proved to be resilient to the aforementioned attacks. Fast and Secure Multihop Broadcast Solutions for Intervehicular Communication
Several IVC applications require multihop broadcast to inform vehicles (and drivers) about road data, delivery announcements, traffic congestion, and proximity with other vehicles, accidents, and even entertainment-related information. The simplest broadcasting mechanism is flooding, where messages are rebroadcast by each receiving node. Although very simple, this technique may lead to high message collision probability and data redundancy, thus becoming rather inefficient. When a message is disseminated to receivers beyond the transmission range, multihopping could be used. However, multihop broadcast can consume a significant amount of wireless resources for unnecessary retransmissions. The broadcast delivery time represents one of the main issues of IVC. It has been proved that this characteristic is strictly related to both the number of relays of the messages (hops) and the network congestion.
The demand-driven transmission protocol adjusts the timing of rebroadcast packets such that the vehicle that is farthest away from the source node retransmits earlier than the other nodes. Ad hoc multihop broadcast and urban multihop broadcast are proposed in for vehicular networks. These protocols are designed to address the broadcast storm, hidden node, and reliability problems in multihop broadcast. Sender nodes try to select the farthest node in the broadcast direction to assign the function of forwarding and acknowledging the packet without any a prior topology information.
In this paper, we analyze the security of a representative algorithm for state-of-the-art IVC-based safety applications and propose countermeasures to handle the security threats. In particular, we focus on one of the main threats to safety application: the possibility of attacking the protocol to impede its useful service. For ease of exposition but without loss of generality, we particularly focus on FMBA, because it embodies both a state-of-the-art solution and a representative example of the IVC-based vehicular safety applications class possessing all the five properties mentioned in Section I. Indeed, problems and possible countermeasures that were identified for FMBA can also be adapted to other protocols/algorithms that belong to the same general class of applications sharing the aforementioned set of properties.
Named data networking (NDN) is a newly proposed architecture for the future Internet that replaces the Internet Protocol end-to-end communication model with a request/reply model to directly retrieve data by application data names; distributed caching among participating nodes is exploited to this aim. This technology has also recently been proposed for vehicular networks. Although few works have recently shed light on significant privacy issues for NDN and shown the feasibility of DoS attacks that may render caching and routing inoperative a comprehensive analysis of security issues and related solutions for vehicular networks is still lacking. Furthermore, we also highlight the possibility of leveraging frequency-modulation radio channels for (malicious) IVC communication.