Research On Blockchain Based Distributed Key Management And Cross Chain Mechanism

With the vigorous development of vehicular networks technologies such as autonomous driving and in-vehicle applications,vehicular networks face limited computing resources and a shortage of storage resources.Mobile edge computing technology provides powerful storage and computing resources for vehicles by deploying edge servers.In vehicular edge computing,the edge server is usually deployed on the Road Side Unit(RSU),and the RSU equipped with the edge server can provide computing offloading services for nearby vehicles.However,the task of unloading to the edge server usually includes sensitive data and private data.In order to avoid information disclosure,data integrity and confidentiality should be ensured.As one of the key technologies to ensure network security,key management is conducive to solving the above problems.However,the traditional key management scheme has the problems of high communication overhead and high delay,which is not suitable for vehicular edge computing.Based on the above background,this thesis studies how to establish an efficient distributed key management mechanism combined with blockchain technology in the vehicular edge computing scenario.The main work is as follows:First,for vehicular edge computing,a distributed key management scheme integrating mutual authentication is proposed.The proposed scheme completes the full life cycle management of keys based on permissioned blockchain,including key generation,storage,update,and revocation.Secondly,in order to simplify the key revocation and key update process,a public key registry is introduced into the blockchain transaction,and the key revocation and update are completed by updating the registry.On this basis,considering the authentication delay caused by the frequent switching of vehicles between edge servers,a lightweight mutual authentication protocol is proposed.Finally,the simulation results show that the proposed scheme has lower authentication delay,less communication overhead,and higher security than traditional key management schemes.Second,considering the problem of low consensus efficiency when the number of nodes in the permissioned blockchain is too large,a crosschain data migration mechanism that supports large-scale key management is proposed.In the proposed scheme,a single chain is divided into multiple parachains,and the parachains complete the key management of vehicles in a certain area,which reduces the number of licensed blockchain nodes,improves consensus efficiency and reduces storage pressure.On this basis,a data migration mechanism between parallel chains is designed based on the relay chain.In this mechanism,cross-chain transactions that require data migration are first collected through the data collection mechanism.Secondly,the relay chain nodes are randomly selected among the parachain nodes through the election algorithm,and the improved Tendermint consensus mechanism is used to complete the data upload to ensure the security of data migration.Finally,the experimental results show that the proposed scheme has lower authentication delay,less communication overhead,and higher security than traditional schemes.