The Impact of Dissimilarity and Redundancy on the Reliability of DSRC Safety Applications

Intelligent Transportation Systems (ITS) are considered one of the most critical infrastructures. For wireless communication ITS use communication links based on Dedicated Short Range Communication (DSRC) in Wireless Access in Vehicular Environments (WAVE) systems, which is a promising technology to improve traffic safety and reduce highway fatalities. Much research has focused on supporting WAVE safety applications, which depend on many message types. The most important message related to safety applications is the Basic Safety Message (BSM), as defined in the SAE J2735 Message Set Dictionary Standard. Thus, this paper focuses on the reliability of safety applications in the presence of jamming attacks affecting BSM. The case of a constant jammer is considered under the assumption that its capabilities are limited to the technical specifications of the vehicles On-Board Unit (OBU), a device that is readily available for purchase. A communications architecture for safety applications is defined that considers dissimilarity and redundancy to overcome the effects of jamming. The dual and triple-redundant schemes presented enable channels with higher power ratings to communicate the needed BSM data to safety applications. This is accomplished without making any assumptions deviating from the existing standards. Using the Forward Collision Warning safety application, it is shown that the redundancy schemes can effectively overcome the impact of jamming. Furthermore, it is shown that the use of 12 Mbps communication speed is not advisable under the adversary model.