As an important part of smart cities, vehicle ad hoc networks (VANETs) have attracted much attention from both industry and academia. In a VANET, generating a secure session key to facilitate subsequent data-in-transit transfer between two or more vehicles is crucial, which can be achieved by using an authenticated key agreement protocol. However, most of the existing identity-based two-party authenticated key agreement protocols have significant computational requirements or are known to be insecure. Thus, in this paper, a secure and efficient identity-based two-party authenticated key agreement protocol is presented by us. This protocol does not involve complex bilinear pairing computations and can generate a valid session key in two rounds. The security of the proposed protocol is proved in the eCK model which has better capability to describe a protocol’s security than the famous CK model, and it has been widely used in the security proof of ID-based key agreement protocols currently. Additionally, we also evaluate its performance for potential utility in a VANET.

With the rapid development of quantum computing and quantum information technology, the universal quantum computer will emerge in the near decades with a very high probability and it could break most of the current public key cryptosystems totally. Due to the ability of withstanding the universal quantum computer’s attack, the lattice-based cryptosystems have received lots of attention from both industry and academia. In this paper, we propose an identity-based blind signature scheme using lattice. We also prove that the proposed scheme is provably secure in the random oracle model. The performance analysis shows that the proposed scheme has less mean value of sampling times and smaller signature size than previous schemes. Thus, the proposed scheme is more suitable for practical applications.