PF-IBDA: Provably secure and pairing-free identity-based deniable authentication protocol for MANET environments

Abstract

Mobile Adhoc Network (MANET) is used in various real-time applications, such as e-voting, army tactical communication, health-care applications, disaster rescue, online message exchange, etc. However, source authentication and deniability are essential properties in such applications. Typically, these properties can be achieved using a deniable authentication (DA) protocol. With the help of a DA protocol, a mobile receiver node can directly verify the source, another mobile node, of a message without consulting a trusted third party (TTP). Recently, many identity-based deniable authentication (IBDA) protocols have been proposed. Most of these protocols are insecure and computationally expensive since they use costly operations, such as bilinear pairing and map-to-point hash function. We proposed a pairing-free identity-based deniable authentication (PF-IBDA) protocol for MANET environments. We proved that the PF-IBDA protocol could provide indistinguishability against adaptive chosen ciphertext attack (IND-CCA2) in the random oracle model (ROM) based on the hardness assumption of the elliptic curve computational Diffie–Hellman (ECCDH) problem. We have computed the execution time of PF-IBDA protocol in different security levels: 80-bit, 112-bit, 128-bit, 192-bit, and 256-bit on a mobile device using the JPBC library and compared it with the state-of-the-art IBDA protocols. We found that the proposed PF-IBDA protocol is more efficient than the existing IBDA protocols.