Biblio

A two-factor authenticated key-agreement scheme for session initiation protocol emerged as a best remedy to overcome the ascribed limitations of the password-based authentication scheme. Recently, Lu et al. proposed an anonymous two-factor authenticated key-agreement scheme for SIP using elliptic curve cryptography. They claimed that their scheme is secure against attacks and achieves user anonymity. Conversely, this paper's keen analysis points out several severe security weaknesses of the Lu et al.'s scheme. In addition, this paper puts forward an enhanced anonymous two-factor mutual authenticated key-agreement scheme for session initiation protocol using elliptic curve cryptography. The security analysis and performance analysis sections demonstrates that the proposed scheme is more robust and efficient than Lu et al.'s scheme.