Quantum dialogue can realize the mutual transmission of secret information between two legal users. In most of the existing quantum dialogue protocols, the information carriers applied in quantum dialogue are discrete variable (DV) quantum states. However, there are certain limitations on the preparation and detection of DV quantum states with current techniques. Continuous variable (CV) quantum states can overcome these problems effectively while improving the quantum channel capacity. In this paper, we propose a quantum dialogue protocol with four-mode continuous variable GHZ state. Compared with the existing CV-based quantum dialogue protocols, the protocol allows two users to transmit two groups of secret information with different lengths to each other simultaneously. The channel capacity of the protocol has been improved as each traveling mode carries two- or four-bits of information. In addition, the protocol has been proved to be secure against information leakage problem and some common attacks, such as beam splitter attack and intercept-and-resend attack.
Quantum dialogue can realize the mutual transmission of secret information between two legal users. In most of the existing quantum dialogue protocols, the information carriers applied in quantum dialogue are discrete variable (DV) quantum states. However, there are certain limitations on the preparation and detection of DV quantum states with current techniques. Continuous variable (CV) quantum states can overcome these problems effectively while improving the quantum channel capacity. In this paper, we propose a quantum dialogue protocol with four-mode continuous variable GHZ state. Compared with the existing CV-based quantum dialogue protocols, the protocol allows two users to transmit two groups of secret information with different lengths to each other simultaneously. The channel capacity of the protocol has been improved as each traveling mode carries two- or four-bits of information. In addition, the protocol has been proved to be secure against information leakage problem and some common attacks, such as beam splitter attack and intercept-and-resend attack.
Quantum dialogue allows both communication parties to execute secure direct communication simultaneously and bidirectionally. In recent years, due to the possible applications of quantum communication technologies in military, finance, medicine and other fields, quantum dialogue has been widely concerned. In the year of 2017, NR Zhou et al designed a new quantum dialogue protocol by using the continuous-variable two-mode squeezed vacuum states, where the two communication parties encode their own secret information into the entangled optical modes with the translation operations and each communication party could deduce the secret information of their counterparts with the help of his or her secret information and the Bellbasis measurement results [1]. LH Gong et al devised an efficient three-party quantum dialogue protocol based on the continuous variable GHZ entangled states [2]. NR Zhou et al proposed a secure quantum dialogue protocol based on single-photons, which not only overcomes information leakage but also possesses an acceptable efficiency. M Xiao et al presented a novel quantum dialogue protocol without information leakage over the collective noise channel, where the logical qubits and four-qubit decoherence-free states were introduced to resist against collective-dephasing noise, collective-rotation noise and all kinds of unitary collective noise [4]. T Hwang et al proposed an authenticated quantum dialogue based on Bell states, allowing two communicators to perform mutual authentication and secure bidirectional communications simultaneously via public classical channels [5]. TY Ye proposed a quantum dialogue scheme by employing logical Bell states as the quantum resource to combat the collective-dephasing noise and the collective-rotation noise, which can accomplish the mutual identification and the dialogue between two participants simultaneously and securely over one kind of collective noise channels [6]. M Wang et al proposed a quantum dialogue protocol based on four-qubit entangled state, which is constructed by an EPR pair and two different single qubits through three Controlled-Not gates [7]. By using Bell measurements and the corresponding unitary operations, two users can exchange their messages simultaneously and directly without sharing any secret keys beforehand. The above protocols exploited different quantum states and involved two or three communication parties basically. These protocols cannot satisfy the practical applications of quantum dialogue in future possible quantum communication networks. Therefore, we will propose a multiparty continuous variable quantum dialogue protocol. Multiparty quantum dialogue protocol enables multiple communication parties to transmit and/or receive information at the same time. The protocol could ensure that there is no information leakage in the communication process according to the uncertainty principle and quantum non-cloning theorem.
We present a quantum dialogue protocol by using the Greenberger-Horne-Zeilinger (GHZ) state. In this paper, we point out that the `quantum dialogue' communication scheme recently introduced by Nguyen can be eavesdropped on under an intercept-and-resend attack. We also give a revised control mode to detect this attack. Hence, within the present version two users can exchange their secret messages securely and simultaneously, and the efficiency of information transmission can be successfully increased.
In quantum cryptography,it is commonly established that quantum key distribution and quantum secure direct,communication work in a single direction,namely one direction communication schemes. However,quantum dialog protocol can enable two legal users exchange messages simultaneously,namely two direction communication.Most existed proposals of quantum dialog protocol are based on discrete variables, which are much more difficult to implement with today's technology,thus they are less practical than its counterpart.Based on squeezed states,a new quantum dialog scheme is proposed,information-theoretical analysis is then followed and it shows that our scheme is not only secure,but also has larger channel capacity than that of its counterpart.
Drawing on the idea of the quantum secure direct communication(QSDC),a novel quantum dialogue scheme based on Bell states is presented in this paper.The proposed scheme can realize authorized parties' secure exchange of their respective secret messages simultaneously only through one communication.In this scheme,a random bit string and checking particles are used to ensure the security;the scheme is secure against eavesdropper's commonly used attacks,such as intercept/resend attack,Trojan horse attack and entanglement attack.A serious problem called leakage or correlation is found in some quantum dialogue protocols,namely,any eavesdropper can elicit some information about the secret from the classical communication of the legal users.Fortunately,our protocol can discard the drawback leakage.In addition,our protocol possesses high efficiency 66.7% and is feasible.Finally,the protocol is applied to the scheme based on two-qutrit entangled states with a secure communication.
A continuous variable (CV) controlled quantum dialogue (QD) scheme is proposed. The scheme is further modified to obtain two other protocols of (CV) secure multiparty computation. The first one of these protocols provides a solution of two-party socialist millionaire problem, while the second protocol provides a solution for a special type of multi-party socialist millionaire problem which can be viewed as a protocol for multiparty quantum private comparison. It is shown that the proposed scheme of (CV) controlled (QD) can be performed using bipartite entanglement and can be reduced to obtain several other two- and three-party cryptographic schemes in the limiting cases. The security of the proposed scheme and its advantage over corresponding discrete variable (DV) counterpart are also discussed. Specifically, the ignorance of an eavesdropper, i.e., information encoded by Alice/Bob, in the proposed scheme is shown to be more than that in the corresponding (DV) scheme, and thus the present scheme is less prone to information leakage inherent with the (DV) (QD) based schemes. It is further established that the proposed scheme can be viewed as a (CV) counterpart of quantum cryptographic switch which allows a supervisor to control the information transferred between the two legitimate parties to a continuously varying degree.
Abstract A new quantum network dialogue protocol is designed by using the entanglement property of the continuous-variable single-mode squeezed states. To verify the security of the channel in the protocol, Alice should send single-mode squeezed states respectively to Bob, Charlie, and etc. Then Bob, Charlie et al could encode the secret information with a specific encoding rule, insert the Gaussian random data into the encoded message and send them to Alice. They could deduce the secret information of their counterparts according to the measurement results. In addition, each communication party could dialogue with another communicator in a quantum way. The new proposed quantum network dialogue protocol based on single-mode squeezed states is much easier to implement compared with those based on the discrete-variable quantum states.