Three quantum dialogue protocols with identification are proposed under the condition of collection noise. They are used to resist collective-dephasing noise, collective-rotation noise and both collective noises respectively. The two communication parties encode their own secret information into the quantum states with the generalized unitary transformation. Each communication party can deduce the secret message of his counterpart according to his secret message and the two quantum states (one is quantum state before being encoded, and the other is quantum state after being encoded), to achieve a quantum dialogue. It is important that our protocols all should be able to resist various attacks, such as disturbance attack, Trojan horse attack, intercept-resend attack and entanglement measure attack. Moreover, the efficiency and the information leakage of the proposed protocol are analyzed in detail.
Three quantum dialogue protocols with identification are proposed under the condition of collection noise. They are used to resist collective-dephasing noise, collective-rotation noise and both collective noises respectively. The two communication parties encode their own secret information into the quantum states with the generalized unitary transformation. Each communication party can deduce the secret message of his counterpart according to his secret message and the two quantum states (one is quantum state before being encoded, and the other is quantum state after being encoded), to achieve a quantum dialogue. It is important that our protocols all should be able to resist various attacks, such as disturbance attack, Trojan horse attack, intercept-resend attack and entanglement measure attack. Moreover, the efficiency and the information leakage of the proposed protocol are analyzed in detail.
In this paper, two robust quantum dialogue (QD) protocols against collective-dephasing noise and collective-rotation noise are presented, respectively. In each of the proposed QD protocols, four logical Bell states, each of which is made up of four physical qubits, are used to combat collective noise. The information leakage problem is overcome by directly transmitting the auxiliary logical Bell states in two steps from one communication party to the other. For decoding, Bell state measurements rather than four-qubit joint measurements are used. The effectiveness against an eavesdropper's active attacks such as the intercept-resend attack, the measure-resend attack, the entangle-measure attack and the Trojan horse attack can be guaranteed.
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.
In this paper, a quantum dialogue (QD) protocol without information leakage is proposed at first by using single photons as the quantum resource, where each single photon is directly encoded for transmitting secret messages. Two communication parties share the quantum state generation rule in advance. The preparation party reads out the other party's secret messages by virtue of quantum secure direct communication. The other party decodes out the preparation party's secret messages with the aid of a classical information sequence indicating the preparation bases of single photons sent from the preparation party. In this way, the information leakage problem is avoided. The proposed protocol with single photons only needs the single-photon measurements. Different from Shi's two recent QD protocols based on single photons, the proposed protocol with single photons needs neither to prepare two adjacent single photons in the same quantum state nor to perform the controlled-not (CNOT) operations. Finally, the proposed protocol with single photons is generalized into the cases of resisting collective-dephasing noise and collective-rotation noise by using logical qubits as the quantum resource, respectively.
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.
In this paper, two robust quantum dialogue (QD) protocols over collective-dephasing noise channel and collective- rotation noise channel are proposed, respectively, by using three-qubit entangled states as the initial quantum resource. Alice generates a series of three-qubit entangled states and divides them into a physical qubit sequence and a logical qubit sequence. Then, Alice sends the logical qubit sequence to Bob. Afterward, Alice and Bob measure the physical qubit sequence and the logical qubit sequence, respectively. According to his measurement result, Bob generates a new logical qubit sequence with no measurement performed. Then, Bob encodes his secret messages on the new logical qubit sequence by performing logical unitary operations on it. Afterward, Bob sends the encoded logical qubit sequence back to Alice. Finally, Alice encodes her secret messages on the encoded logical qubit sequence from Bob by performing logical unitary operations on it and publishes her measurement. As a result, Alice and Bob can decode out each other's secret messages. By virtue of the measurement correlation of three-qubit entangled states, two participants share the initial states of message logical qubits privately. In this way, the information leakage problem is overcome. The proposed protocols only need the single-photon measurements. Compared with previous QD protocols workable over collective noise channels, the proposed protocols have the highest information-theoretical efficiency.
Quantum system is inevitably affected by the external environment in the real world. Two controlled quantum dialogue protocols are put forward based on logical χ-type states under collective noise environment. One is against collective-dephasing noise, while the other is against collective-rotation noise. Compared with existing protocols, there exist several outstanding advantages in our proposed protocols: Firstly, the χ-type state is utilized as quantum channels, it possesses better entanglement properties than GHZ state, W state as well as cluster state, which make it difficult to be destroyed by local operations. Secondly, two kinds of logical χ-type states are constructed by us in theory, which can be perfectly immune to the effects of collective noise. Thirdly, the controller can be offline after quantum distribution and permission announcement, without waiting for all the participants to complete the information coding. Fourthly, the security analysis illuminates that our protocols can not only be free from the information leakage, but also resist against the intercept-and-resend attack, the entanglement-and-measure attack, the modification attack, the conspiring attack, and especially the dishonest controller’s attacks.