Efficient Self-Certified Blind Signature Scheme with Parings

Abstract

Blind signature is a special anonymous technique, it can realize the anonymity of the signed message. A common blind signature is achieved in PKI and ID-based cryptography. However, self-certified signature scheme is a better choice than that in traditional public key system and ID-based cryptography, since it omits key escrow problem of ID-based crypto-system and avoids complex certificate management of traditional PKI. In the work, we first formalized the security models of self-certified blind signature by classifying its adversary types. Then, we proposed a concrete instance. And we also show that the proposed scheme is provably secure in the random oracle models and the security of the scheme is closely related to a extended security assumption: q-SDH+CDH assumption which is provided by us. And we show that the proposed scheme is very efficient in terms of computational costs of generation and verification of a signature. Because no pairing operator is required in the signing phase of our scheme, thus our blind signature scheme is very efficient in terms of computational cost.