Shorter Verifier-Local Revocation Group Signature with Backward Unlinkability

Used as the privacy-preserving attestation by Trusted Computing effort (TCG) or the privacy-preserving authentication protocol in vehicular ad hoc networks (VANETs), group signature becomes more important than ever. Membership revocation is a delicate issue in group signatures. Verifier-local revocation (VLR) is a reasonable resolution, especially for mobile environments. Back unlinkability (BU) is a currently introduced security property providing further privacy. Based on the Decision Linear (DUN) assumption and the q-Strong Diffie-Hellman (q-SDH) assumption, a new BU-VLR group signature scheme is proposed, which has the shortest signature size and smallest computation overhead among the previous BU-VLR group signature schemes.