Research On Certificateless Anonymous Authentication Scheme And Group Key Agreement Scheme In VANETs

In recent years,with the continuous development of wireless communication technology,the VANET(Vehicular Ad Hoc Network)has played an increasingly important role in intelligent transportation,such as reducing accident rates and improving traffic efficiency.However,due to its openness,it is more vulnerable to internal and external attacks,and due to the high-speed mobility of vehicles,malicious messages will seriously threaten the safety of life and property,so the key task is to efficiently protect the information security of VANET.The above issues have been extensively researched in recent years.For example,anonymous identity authentication scheme is proposed to ensure the legitimacy and privacy of users,and group key agreement scheme is used to ensure the security of message content,but its security and efficiency need to be further improved,this thesis conducts a further study on this.Aiming at the demand for identity authentication in VANET,an efficient certificateless aggregate signature-based anonymous authentication scheme is proposed.Based on elliptic curve cryptosystem,a vehicle private key is constructed with partial private key generated by KGC and secret value selected by the vehicle.The vehicle private key is used to construct the certificateless signature,and the signature aggregation algorithm is constructed based on the addition operation on the elliptic curve to realize the batch verification of signatures.Construct a real-time updated pseudonym for the vehicle to protect the privacy of the vehicle.When a dispute occurs,the real identity of the vehicle can be traced through the pseudonym.Security analysis shows that the scheme has the ability to resist a variety of attacks.Random oracle model is used to prove the security of the scheme,which shows that the signature is unforgeable when facing internal and external attackers.The scheme meets the requirements of identity authentication and conditional privacy protection in VANET.Simulation analysis results show that this scheme meets the high-efficiency requirements of VANET.Aiming at the demand for efficient encrypted communication in VANET,a Chinese remainder theorem based efficient group key agreement scheme is proposed.The scheme includes two parts: identity authentication and key agreement.Using chaotic mapping to construct the identity authentication process,a pseudonym pool is generated for vehicles based on true identity,vehicles use the pseudonym to protect the communication privacy.When a dispute occurs,the real identity of the vehicle can be traced through the pseudonym.As the group manager,the RSU decides the size of the group.TA manages the group member through the RSU list and performs key agreement for the group member.RSU is responsible for group key distribution,and the vehicles use session key generated from the group key to encrypted communication in the group.CRT based efficient group key update process is constructed to ensure the forward and backward security of the group key.The scheme ensures the content security of communication and meets the requirements for efficient encrypted communication in VANET.The formal analysis of BAN logic shows that the scheme has reached the safety goal.The simulation analysis results show that this scheme meets the high-efficiency requirements of VANET.