Convertible undeniable signature with subliminal channels

The concept of subliminal channel was first proposed in 1983. After that, many subliminal channel schemes based on digital signatures are proposed. A convertible undeniable signature is an undeniable signature and can be converted to a general digital signature. In this paper, we combine both concepts to propose a new scheme which can embed subliminal channels into a convertible undeniable signature scheme. The proposed scheme keeps all properties of the convertible undeniable signatures and can be used to transmit different subliminal messages to different subliminal receivers. Moreover, the subliminal receivers need not share any secret key with the sender. (C) 2003 Elsevier Inc. All rights reserved.