Identity-Based Secret Signature Scheme

Secret signature, proposed by Lee et al. [11], is a new signature scheme which provides signature privacy and public provability together. Using the secret signature scheme a signer can send his signature secretly to a specific receiver such that only the designated receiver can verify the signature. If any argument occurs between them, the validity of the secret signature can be proven publicly either by the signer or the receiver. Thus it can be used as an important cryptographic primitive to implement private business transactions. In this paper we present an identity-based implementation of secret signature scheme which can enjoy the advantage of reducing key management load compared with the traditional certificate-based cryptography. We modify Cha-Cheon's ID-based signature scheme [3] and ID-based key agreement scheme [14] to provide public provability, and then combine them to implement ID-based secret signature (IBSS) scheme.