Chiang Mai Journal of Science

 Deniable authentication is a new cryptographic technique of authentication, by which it allows the sender to prove his legitimacy to the intended receiver, but the intended receiver cannot prove to the third party the identity of the sender. Meanwhile, in order to meet various circumstances of the resource limit mobile devices, Lu and Cao proposed a non-interactive deniable authentication protocol from bilinear pairings to achieve above properties and to reduce communication and computation costs; however, there are areas of improvement. This paper first reviewed how a receiver can convince the third party the identity of the sender by revealing some information in Lu and Cao’s protocol; then proposed a novel deniable authentication protocol from pairings to exterminate such security defect internally in Lu and Cao’s protocol. Furthermore, we demonstrated that the proposed protocol is more efficient than the previously deniable authentication protocols in terms of the communication costs and the computational complexities.