Broadcast Storm Mitigation of ESMs Using Spectrum Sharing in Cognitive Radio VANETs

Security applications in vehicular ad-hoc networks (VANETs) must guarantee reachability and an efficient transmission of emergency messages. The use of cognitive radio technology certainly enhance the performance of vehicular networks, giving rise to Vehicular Cognitive Radio Networks (COG-VANETS). In this paper, a MAC protocol for the transmission of emergency security messages (ESMs) in COG-VANETS is evaluated using both the TV white spaces (TVWS) band and the DSRC band following a spectrum sharing approach. Nevertheless, an scenario of broadcast storm is considered and hence a mitigation technique is incorporated to the MAC protocol with the objective of reducing the problem of broadcast storm which is presented in vehicular communication when the number of vehicles is high and all want to broadcast emergency messages.