Research On Privacy Protection Method Of Sensor-cloud Based On Local Differential Privacy

Cloud computing technology introduced Wireless Sensor Networks(WSN),and then scholars proposed sensor-cloud system.It not only inherits the ubiquitous physical characteristics of WSN,but also has the advantages of cloud computing in terms of stored data and computing power.However,sensor-cloud is still in the research and development stage,and there are still some problems that need to be solved.On the one hand,the base station is the convergence point of all data,and the privacy of its location is extremely important.On the other hand,the special characteristics of the sensor-cloud itself lead to the data of sensor nodes being vulnerable to malicious attacks in the process of collection and transmission,so the research on its data privacy is also a big challenge.Therefore,this paper investigates and analyzes the privacy issues of base station locations and data in sensor-cloud,and finds that it is an urgent problem to build a secure and efficient privacy protection model for sensor-cloud.First of all,in view of the privacy security issues such as location information leakage in the interaction process between the base station and the sensor nodes in the sensor-cloud system,a base station location privacy protection algorithm based on local differential privacy(LDP)is proposed.Firstly,through the local obfuscation algorithm(LOA),the base station can get the data of the real location and the pseudo location by flipping a coin,and then send the data to the fog layer,then the obfuscation location domain set is obtained.Secondly,the location domain of the base station is divided into several decentralized sub-regions,and a privacy location reconstruction algorithm(PLRA)is performed in each sub-region,in order to reconstruct the location distribution of the real location and the pseudo location in the base station.Finally,the base station correlates the location information of each sub-region,and then uploads the data information containing the disturbance location to the fog node layer.Secondly,aiming at the problem of data leakage in the process of collection,transmission and query of sensing data collected by sensor nodes in sensor cloud system,a data privacy protection method based on local differential privacy is proposed.Firstly,the nodes in the network are clustered and different binary trees are created.Then the intra-cluster differential privacy protection technique is used to add noise perturbations to the clusters using Laplace mechanism to obscure the real data information.Finally,using inter-cluster differential privacy protection between clusters,asymmetric keys are assigned to the base station nodes and sensor nodes to encrypt and add noise,and after the base station receives the data,the private key is used to decrypt and remove noise from the data.Last but not least,in this paper,PA-PLRA and LDPP are verified by simulation experiments.PA-PLRA is validated in terms of authentication protocol,privacy security,algorithm running time,data availability and network model simulation.The simulation results show that PA-PLRA can reduce the algorithm's running time and network delay,and improve the data availability,which can protect the base station location privacy more safely and efficiently.LDPP is analyzed in terms of communication expenses,privacypreserving performance and running time,showing that the LDPP can reduce communication overhead and running time,and has better privacy protection.