Efficient deniable authentication protocol based on generalized ElGamal signature scheme

An efficient and non-interactive deniable authentication protocol is presented to enable a receiver to identify the source of a given message, but not prove the identity of the sender to a third party. The proposed protocol is based on the generalized ElGamal signature scheme and is more efficient than the previous protocols. We show that if an adversary could forge signatures of this protocol, he would forge signatures of the generalized ElGamal signature scheme. Moreover, the new protocol is more secure than the previous deniable authentication protocols, since anyone can not impersonate the intended receiver. D 2003 Elsevier B.V. All rights reserved.