A quantum identity authentication protocol based on continuous-variable entangled light fields

Identity authentication is an important method to ensure the security of information, even for quantum information. A bi-directional quantum identity authentication protocol using a two-mode squeezed state as an entanglement resource is proposed. The decoy states’ sequences are used to enhance the security of the mutual communication process between the legitimate users. The security of the protocol under a Gaussian-cloner attack is investigated in detail with the secret information rate as the major parameters. The results show that the proposed scheme is physically secure and is able to detect possible eavesdroppers.