A New Designated Confirmer Signature Variant with Intended Recipient
Previous designated confirmer signature schemes were less efficient because complex zero-knowledge proof employed in confirmation and disavowal protocol. In this paper, we propose a new efficient signature scheme which is recipient-specific and confirmer-specific. The new scheme is transformed from ID-based chameleon signature and inherits its advantage in simplicity and efficiency. The scheme's security relies on the underlying secure chameleon signature and public key encryption scheme. We also considers the case of confirmer as an adversary in security proof.