Secure and privacy preserving group signature scheme with verifier local revocation

A Group Signature is an improved adaptation of Digital Signature, where a member can sign on behalf of the group in which he belongs. Verifier of signature can only verify the signed message as, is it signed by an authenticate group member or not but cannot identify the individual group member, who was signer of the message, thus protecting group member's anonymity. In some cases of dispute, identification of the signer can be revealed only by authenticate opening entity. Our scheme provides a new approach for privacy management of the signer and also provides full revocation of any member from dynamic group. This scheme also reduces the computational cost of producing the signature as well as revocation cost. The proposed scheme is proved secure and coalition resistance under Decisional Diffie-Hellman assumption and Strong RSA assumption.