| In recent years,VANET(Vehicular Ad-hoc Network)has gradually developed towards networking and intelligence.While providing users with intelligent customized services such as driving navigation and personalized recommendations,it has also brought a series of privacy leakage threats.A common privacy protection method is to use pseudonyms to replace the real identity of the vehicle in the communication process.When the vehicle drives out of the network or acts improperly,the certificate authority CA(Certificate Authority)revokes the pseudonymous certificate issued to the vehicle.CRL(Certificate Revocation List)is usually used to store pseudonymous certificates that have been revoked but not expired.However,the high mobility of vehicles in VANET will rapidly increase the size of the CRL,which will bring additional storage,communication,and computing overhead.This paper mainly studies the issue of pseudonym revocation in VANET,and proposes a pseudonym revocation mechanism based on CRL and Cuckoo filters.This article mainly includes the following aspects:(1)A set of CRL-based management mechanism for revoked pseudonyms is proposed.For the unexpired pseudonym of the revoked identity vehicle,this mechanism selects system initialization,pseudonymous certificate issuance,pseudonymous certificate revocation,expired certificate deletion,vehicle identity authentication and other main scenarios,and describes in detail the communication interaction and message processing between nodes in VANET Process.(2)Based on the above mechanism,a compressed CRL algorithm C3RL based on Cuckoo filter is proposed to further reduce the additional overhead caused by the rapid growth of CRL.This algorithm stores fingerprints instead of complete data items,thereby reducing the storage and communication overhead of the original CRL;proposes the concept of certificate expiration list CEL(Certificate Expiration List),establishes the CRL-CEL index structure,and solves the problem that the table content cannot be used for self-deleting,Which effectively reduces the computational overhead in the verification process.The paper proves the safety of the algorithm from three perspectives:the anonymity of the vehicle,the unforgeability and traceability of the message,and compares it with other algorithms from the perspectives of space efficiency,false positive rate,search efficiency,and cancellation efficiency.Theoretically proved the excellent performance of C3RL in reducing overhead.(3)A C3RL-based simulation system for revoked pseudonym management was built in the Veins simulation tool.The system is divided into road traffic,message processing and pseudonym-CRL modules according to the communication level.The paper designs and implements each module,and tests the system functions. |
