On a group signature scheme supporting batch verification for vehicular networks

Vehicular ad hoc networks (VANETs) have recently attract extensive attentions as a promising technology for improving traffic safety and efficiency. To make VANETs practical, security, privacy and efficiency are important issues. Anonymity preserving of group signature and lower overhead in verification of batch signature make these two kinds of signatures right tools to design VANET communication protocols. In IEEE ICC 2010, a privacy-preserving scheme for VANETs has been proposed, which is proposed by adding batch verification into a short group signature proposed in CRYPTO 2004, in order to offer a privacy-preserving and fast verification message authentication protocol in VANETs. However, we first point out that this scheme is wrong due to the confused computations. Then we propose a new efficient privacy-preserving vehicular communication scheme from the same group signature supporting batch verification.