Reliable traffic information propagation in Vehicular Ad Hoc Networks

Abstract

A vehicular ad hoc network (VANET) allows vehicles to share traffic information and to alert each other of emergency events. To achieve this goal, a security mechanism must be designed to guarantee that no malicious vehicles can intercept, manipulate, or modify the traffic information without being detected. In this chapter, we present two novel approaches to provide reliable traffic information propagation in a VANET: Two-directional data verification, and time-based data verification. The two-directional data verification approach uses vehicles in both driving directions of a two-way road as two separated media channels. A traffic message will be transmitted through 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 and costly to have two collaborative vehicles on both driving directions in the same region. The time-based data verification approach only uses vehicles in the opposite driving direction to propagate a traffic message by first issuing its public key commitment and later sending the actual traffic message. It relies on the time delay between these two messages and the mobility of vehicles to protect data integrity.