Location Privacy-Preservation And Security Policy Deployment For Internet Of Vehicles

With the development of the internet of vehicles,the services provided are diversified,which bring great convenience to people's lives.However,when vehicles want to obtain location-based services(LBSs),they need to provide their real locations,which may lead to the disclosure of vehicles' location privacy.Since the vehicle can also serve as a location service provider,for example,when the vehicle participates in performing tasks based on mobile crowdsensing,the real locations of vehicles are required to match the locations of tasks,and thus location privacy may also be leaked.Moreover,no matter whether the vehicle is getting service or providing service,in order to ensure the security of data transmission,a fine-grained security policy needs to be deployed.Therefore,as for internet of vechicles,location privacy protection mechanism and security policy deployment have become hot topic of research.The existing methods for location privacy preservation and security policy deployment have the following problems: First,due to the characteristics of fast moving vehicles and short contact time between vehicles and Roadside Units(RSUs),traditional location privacy protection mechanisms(such as K-anonymity)are difficult to meet the needs of users' privacy protection and service quality at the same time.Then,in terms of the privacy protection for task allocation,the traditional privacy protection mechanism based on location perturbation or confusion can hardly defense the attackers with prior knowledge.Finally,utilizing software-defined networks,the deployment of security policy for internet of vehicles can be translated into installing flow entries for OpenFlow switches.However,the traditional security policy deployment is difficult to deal with flow path selection with the smallest delay,under different security sensitivity of traffic.Facing with the above problems and challenges,this thesis is conducted from the following three aspects:(1)LBSs acquisition based on location privacy protection in internet of vehicles.By setting caching service content on the RSU,using K-anonymity,a proactive caching strategy based on location privacy protection is proposed,which is proved to be an NP-hard problem.Based on sub-modal optimization,a greedy algorithm is used to solve this problem.Experimental results show that compared with the FIFO mechanism and the NOP mechanism,the proposed strategy can not only satisfy the users location privacy requirement,but also has a high cache hit rate,thus to improve the users service quality.(2)Task allocation based on location privacy protection for internet of vehicles.Based on location differential privacy,a multi-objective optimization model with high availability of perturbation mechanism and high completion rate of task allocation is established.Using Bender decomposition,two sub-problems of location perturbation mechanism optimization and task allocation strategy optimization can be obtained.Then task assignment strategy based on location indistinguishability can be derived through iteration.The experimental results show that,compared with the classic Laplace mechanism and BD mechanism,the scheme proposed shows better performance in terms of the average moving distance and the completion rate of tasks.(3)Security policy deployment for internet of vehicles.With the help of softwaredefined network,the security policy deployment can be transformed into the selection of traffic forwarding path.And an optimization model is proposed that minimizes the delay of traffic forwarding paths for different security sensitivity.Then,Log-det heuristic algorithm can be used to solve it.The experimental results show that,compared with the security transmission strategy in traditional internet of vehicles,the proposed strategy can ensure low transmission delay of security-sensitive traffic,and the overall traffic transmission delay is minimized.In summary,this thesis studies the location service acquisition,location-based task allocation and security policy deployment in the internet of vehicles.using three methods of proactive caching,location differential privacy,and software-defined networking,the location privacy protection and security policy deployment for internet of vehicles can be implemented,thus improving users' quality of services.