Research On Reliable,secure And Privacy Preserving Transmission In The Internet Of Vehicles

The thesis combines the focus area and challenges of the Internet of Vehi-cles(IOV),and studies the performance analysis and optimization of the medium access control(MAC)layer,the pseudonym schemes and resource scheduling to support the reliable and privacy preserving data transmission in the IoV.The main contributions of the thesis can be summarized as follows:1.MAC Layer Performance Analysis and Optimization.In IoV,the design of the MAC layer protocols plays an important role in supporting the reliable and efficient transmission of safety messages.The thesis firstly analyses the transmission performance of the IEEE 802.11p and the distributed time division multiple access(TDMA)based MAC protocols separately.The thesis then proposes a scalable CSMA and TDMA based MAC protocol,namely CS-TDMA.The contributions of CS-TDMA include that:firstly,the protocol combines SDMA,TDMA with CSMA for channel accessing to support reliable broadcast of the safety messages in the IoV;secondly,the dwelling time ratio between the control channel and service channel can be changed in a dynamical and distributed man-ner by each vehicle according to the vehicle density within its geographical area;thirdly,theoretical analysis is presented for CS-TDMA to evaluate its perfonnance in terms of access delay and throughput.Both the theo-retical analysis and simulation results have drawn the high efficiency and effectiveness of CS-TDMA in the supporting of safety messages transmis-sion and the utilization of the channel resource.2.A Distributed MAC Layer Attack Resistant Pseudonym(MARP)Scheme The design of pseudonym schemes and pseudonym changing strategies are of great significance to ensure the identity privacy,non-linkability,non-repudiation and accountability of vehicle entities in the IoV.How-ever,the dilemma between location privacy aind transmission efficiency arises in the IoV.This is because the previous work considers the design of pseudonym scheme for location privacy,and the MAC layer protocols for transmission efficiency separately.In this thesis,the author firstly iden-tify the new MAC layer context-linking attack facilitated by the incon-sistent operation of the pseudonym changing and periodical safety mes-sages transmission.Secondly,the MAC layer attack resistant pseudonym(MARP)scheme is proposed to avoid the new context-linking attack,guar-antee the location privacy and fulfill the transmission requirements.In MARP,vehicles transmit their safety messages in a distributed TDMA based mechanism,use the pseudonyms to protect their identities,and dy-namically construct mix-zones by negotiating with their neighbors to change their pseudonyms and time slots in an indistinguishable manner.Thirdly,an analytical model is proposed to quantify the location privacy achieved in the MARP scheme,in terms of the pseudonym age,anonymity set size and time-to-confusion.Based on the mean field theory,the analyt-ical model derives the cooperation probability among vehicles,which is not related to the transmission pattern when the number of vehicles in the network is large.Extensive simulation results corroborate the analyt-ical model,and verify that the MARP scheme can resist the MAC layer context-linking attack.It shows that the MARP scheme is efficient as it introduces negligible communication overhead and bounded transmission delay.To the best of our knowledge,this is the first work that considers the cross-layer location privacy preservation for the IoV.3.A MAC Layer Aware Pseudonym(MAP)Scheme in the Software Defined Internet of VehiclesTo satisfy the QoS and quality of privacy of data transmission in the IoV,various distributed TDMA MAC schemes and pseudonyms are proposed for the IoV.Nerveless,distributed TDMA MAC protocols lack of flexi-bility under vehicle density variety,and traditional radio access networks(RANs)are cumbersome and prone to errors.Most existing pseudonym management schemes were carried out without considering the effect on the data transmission.The coupling of MAC operation and pseudonym management justify the de-coupling of the control and data plane.The thesis presents a hierarchical architecture,namely the software defined In-ternet of Vehicles.The RSUs are connected together according to the flow tables to manage the vehicles that transmit in the data plane.Facilitated by the architecture,a MAC layer aware pseudonym(MAP)scheme is pro-posed to allocate both the channel resources and pseudonyms for the vehi-cles.RSU clouds allocate transmission time slots to vehicles according to the status of the slots,and the traffic density and mobility.The RSU clouds coordinate vehicles to change their transmission slots and pseudonyms si-multaneously in the mix-zones by determining whether the vehicles can achieve location privacy gains through changing pseudonyms.Security analysis and extensive simulations are conducted to show that the MAP scheme can significantly enhance the location privacy and improve the data transmission efficiency and reliability for the IoV.