Cryptanalysis of an Improvement of Robust Deniable Authentication Protocol

Deniable authentication protocol, as an advanced method of authentication, enables the intended receiver of a given message to identify the source of the message while preventing the receiver to prove this source to a third party. In 2013, Li and Takagi proposed an enhanced model of Yoon et al’s robust deniable authentication protocol and claimed that their model could achieve the property of deniable authenticity. The present study reviews and analyses Li and Takagi’s suggested model and argues that this model still needs improvement to satisfy deniability.

Keywords:

deniable authentication , electronic voting system , ElGamal signature