Reliable traffic information propagation in Vehicular Ad-Hoc Networks

In a Vehicular Ad-Hoc Network (VANET), an important application is to let moving vehicles collaborate with each other by sharing traffic information and alerting others of any emergency or accidental scenarios. To make this application possible, a security mechanism must be designed in the beginning to guarantee that no malicious vehicles or persons can intercept, manipulate, or modify traffic information propagating in a VANET without being detected. In this paper, we present a novel approach to provide reliable traffic information propagation in a VANET: two-directional data verification. Two-directional data verification approach uses vehicles in both directions of a two-way road as two separated media channels to propagate traffic data. By receiving messages from both channels, a recipient vehicle verifies the message integrity by checking if data received from both channels are matched. This approach exploits the fact that it is difficult for an adversary to have two collaborative vehicles on both driving directions in the same region. Even if an adversary can do this, it is costly and attacks can be done only in a short time period. The proposed approach is simple and readily to be implemented, requiring no complicated public-key infrastructure to protect traffic information propagation in VANET.