An Improved Deniable Authentication Protocol Based on Generalized ElGamal Signature Scheme for E-Learning

The importance of correctly identifying and authenticating a student in an e-learning environment comes from the necessity to avoid fraud or cheating. A new deniable authentication protocol based on the generalized ElGamal signature scheme was proposed by Shao in. However, this paper demonstrates that Shao´s protocol has two drawbacks: forward/backward secrecy problem and message confidentiality problem. To mitigate the security breaches, we also propose an improved deniable authentication protocol based on the generalized ElGamal signature scheme that can applicable for E-learning. As a result, the proposed protocol has same efficiency and strong security compared with Shao´s protocol.