Secure message propagation protocols for IoVs communication components Abstract   With the development of Internet of Vehicles (IoVs), the smart transportation field has achieved a lot of attention by providing a wide variety of benefits, such as enhanced road safety, reduced traffic congestion, traveler safety, and less pollution. It made the concept of xe2x80x98intelligence on wheelsxe2x80x99 into a real one. However, the highly dynamic nature of vehicles and insecure channels are the significant challenges in an IoV environment. In the existing researches, secure and lightweight protocols for the IoVs communication components are missing. In this paper, we design secure and lightweight communication protocols for different components of IoVs, such as V2V (VehicletoVehicle), V2P (VehicletoPortable Device), V2R (VehicletoRoad Side Unit), V2I (VehicletoInfrastructure), and V2S (VehicletoSensor). We have done indepth security analysis to ensure the resistant power against different strong attacks. Moreover, we have implemented the protocols on a Desktop Computer and Raspberry Pi. From the results, it is observed that the proposed protocols perform well in the perspectives of communication, storage, computation, and battery consumption than other competitive protocols.

SmartphoneBased Platform for Secure MultiHop Message Dissemination in VANETs Vehicular adhoc Networks (VANETs) are recognized as a cornerstone of Intelligent Transportation Systems (ITS) to enable the exchange of information among vehicles, which is crucial for the provision of safetyrelated and entertainment applications. However, practical useful realizations of VANETs are still missing, mainly because of the elevated costs and the lack of a final standardization. In this regard, the feasibility of using smartphones as nodes in VANETs has been explored focusing on smallscale deployments to mainly validate singlehop communication capabilities. Moreover, existing smartphonebased platforms do not consider two crucial requirements in VANETs, namely, multihop communication and the provision of security services in the message dissemination process. Furthermore, the problem of securing message dissemination in VANETs is generally analyzed through simulation tools, while performance evaluations on smart devices have not been reported so far. In this paper, we aim to fill this void by designing a fully ondevice platform for secure multihop message dissemination. We address the multihop nature of message dissemination in VANETs by integrating a locationbased protocol that enables the selection of relay nodes and retransmissions criteria. As a main distinction, the platform incorporates a novel certificateless cryptographic scheme for ensuring data integrity and nodesxe2x80x99 authentication, suitable for VANETs lacking of infrastructure.