Strong Designated Verifier Signature Scheme: New Definition and Construction
Recently, several strong designated verifier signature schemes have been proposed in the literature. In this paper, the authors first point out that such so-called strong designated verifier signature scheme is just message authentication code HMAC. Without the key property, unforgeability, for signatures, these schemes cannot enable signers to have complete controls over their signatures as demanded by Chaum and Van Antwerpen originally. No signer would use such Designated Verifier Signature schemes if he does not trust the designated verifier entirely. Then they introduce a new notion for the strong designated verifier signature scheme and its security requirements.