Research On Anonymous Authentication Scheme In V2G Environment

As a significant part of smart grid,V2 G can realize the two-way exchange of data flow and power flow between electric vehicles and smart grid.It is an effective promoter to realize the storage and decarbonization of the power grid.However,when electric vehicles are connected to the power grid,V2 G network will involve a large number of privacy data interactions and sensitive charge or discharge transactions.Once these data are leaked,the privacy of users will be threatened.The existing authentication protocols in the V2 G network lack sufficient protection for the identity privacy of users,and cannot provide complete anonymity of users' identities.At the same time,due to the openness and complexity of the V2 G network,most of the existing anonymous authentication protocols have some problems.For example,it is difficult to track malicious vehicles,the authentication process is inefficient,and the revocation management is complicated.To solve the above problems,this paper proposes two anonymous authentication protocols:(1)Anonymous authentication protocol with forward securityTo solve the problem that the identity privacy of users is easy to be leaked in the authentication process,an anonymous authentication protocol with forward security is proposed in this paper.Firstly,the protocol verifies the user's identity based on multiple factors such as biometric value,which is to provide preliminary security for vehicles to join into the power grid and subsequent charge or discharge transactions.Secondly,electric vehicles generate signatures based on non-interactive zero knowledge proofs to prove that they have legal authorization certificates.And the certificate is blinded to hide the user's identity.In the case of the conspiracy between the semi-trusted server and the adversary,it is difficult to expose the user's real identity,which is to fully protect the privacy of the vehicle users.Finally,theoretical analysis and experimental simulation show that the protocol meets multiple security objectives such as unforgeability and forward security,and has lower computation and communication overhead compared with the same type of protocols.(2)Anonymous authentication protocol with conditional privacy preservationTo solve the problems that tracking malicious vehicles is difficult,authentication efficiency is low,and revocation management is complicated in the authentication process,an anonymous authentication protocol with conditional privacy preservation based on protocol 1is proposed in this paper.Firstly,based on the distributed key generation technology,the protocol designs a decentralized mechanism to track malicious vehicles identities.This mechanism disperses the authority to obtain the user's real identity to multiple vehicle operation centers,and effectively resist the single point of failure attack.Secondly,the protocol introduces a batch verification algorithm to improve authentication efficiency.In addition,when there is a revoked vehicle,the protocol supports the vehicle to update the non-revoked witness,which not only saves the computation cost of the registration center but also avoids the rapid expansion of the revocation list.Finally,theoretical analysis and experimental simulation show that the protocol can resist multiple security attacks such as privilege internal attack and man-in-the-middle attack,and has good scalability when facing large-scale vehicle groups.