Consider in an asymmetric scenario that Alice and Bob wish to communicate unequal amount of classical information, we propose an asymmetric quantum dialogue (QD) protocol based on the entanglement swapping between two-qubit bell state and four-qubit cluster state. In this scheme, assume that there are two legitimate participants Alice and Bob. In a dialogue, the information that is delivered by Alice to Bob is twice the amount of her information obtained from Bob. The analysis demonstrates that our protocol is efficient and can meet the requirements of unequal amount of information transmission in a real communication scenario. Moreover, we discuss the security of this protocol and it demonstrates that our protocol could resist an external attack.
Consider in an asymmetric scenario that Alice and Bob wish to communicate unequal amount of classical information, we propose an asymmetric quantum dialogue (QD) protocol based on the entanglement swapping between two-qubit bell state and four-qubit cluster state. In this scheme, assume that there are two legitimate participants Alice and Bob. In a dialogue, the information that is delivered by Alice to Bob is twice the amount of her information obtained from Bob. The analysis demonstrates that our protocol is efficient and can meet the requirements of unequal amount of information transmission in a real communication scenario. Moreover, we discuss the security of this protocol and it demonstrates that our protocol could resist an external attack.
In order to avoid the risk of information leakage during the information mutual transmission between two authorized participants, i.e. Alice and Bob, a quantum dialogue protocol based on the entanglement swapping between any two Bell states and the shared secret Bell state is proposed. The proposed protocol integrates the ideas of block transmission, two-step transmission and unitary operation encoding together using the Bell states as the information carriers. Besides the entanglement swapping between any two Bell states, a shared secret Bell state is also used to overcome the information leakage problem, which not only makes Bob aware of the prepared initial state but also is used for Bob's encoding and entanglement swapping. Security analysis shows that the proposed protocol can resist the general active attacks from an outside eavesdropper Eve. Moreover, the relation between the maximal amount of information Eve can gain and the detection probability is derived.
In this study, a protocol for secure quantum dialogue using entanglement swapping was proposed. The protocol employs two independent communication channels, a classical channel and a quantum channel. In this scheme, the legitimate communicators Alice and Bob can pass the authentication by the classical trusted channel. Afterwards, a quantum channel sequence is provided for them, on which Alice and Bob can communicate with each other directly and privately by virtue of some encoding operations. The first advantage of our protocol is that different from the previews protocols, in the proposed protocol, the server of the quantum channel, Charlie, is not necessarily trusted. The other highlight of our protocol is that in the presented scheme, one party is able to first read the message received from the other party before sending another message back in reply.
Key words: Quantum secure direct communication, entanglement swapping, quantum dialogue.
In this paper, a controlled quantum dialogue (CQD) protocol based on Brown states is proposed. In the beginning, the controller Cindy creates a five-qubit Brown state as the channel and distributes it to the other two communication participants, Alice and Bob. Then, Alice and Bob can encode the secret key by performing unitary operation onto the entangled particles that Cindy sends to them. Finally, the messages can be exchanged by entanglement swapping and the results of Bell state measurement. The security analysis shows that our protocol cannot only solves the problem of information leakage, but also can effectively prevent a variety of well-known attacks. Under the control of Cindy, there are two possible decoding methods for participants to obtain each other's information, improving communication security. In addition, this protocol does not involve complex quantum operations and demonstrates a good physical operational feasibility.
Abstract Quantum dialogue enables two communicators to send their own secret information to each other, but most of the current quantum dialogue protocols have high requirements for the hardware equipment and capabilities of the communicators. In order to reduce the cost of participant, a semi-quantum dialogue scheme based on hyperentangled Bell states is studied in this paper. In our protocol, we combines the idea of semi-quantum key distribution and semi-quantum secure direct communication to realize the exchange of secret information between Alice and Bob, Alice’s information is transmitted to Bob through semi-quantum secure direct communication, while Bob’s message is extracted by Alice through semi-quantum key distribution and one-time pad encryption. This is different from the previous semi-quantum dialogue protocols, and is a new way of thinking. The security analysis shows that our protocol can not only resist the conventional attack strategies, but also has not the drawback of ‘information leakage’ problem. Compared with the existing semi-quantum dialogue protocols, it has some advantages, such as high communication efficiency, saving classical participant’s consumption and security. Although this protocol requires the preparation and analysis of hyperentangled Bell state, which are slightly more complex, it will be shown that all these are achievable by current technology. Our protocol is fully implementable, so it has good application prospects.
Abstract A controlled semi-quantum dialogue protocol is proposed that uses semi-quantum cryptography and the concept of ‘control’. In this scheme, the supervisor Charlie prepares a large number of entangled photon pairs and separates them into an S A for verification and an S B for encoding. The quantum-capable party Alice and the classical communication party Bob proceed to encode on the S B sequence only after confirming the security of the channel. Finally, Alice performs measurements and announces the results to finalise the communication. This protocol ensures that secret information is exchanged between Alice and Bob only with Charlie’s permission, while Charlie has no access to the communicators’ secret information during the whole process. In terms of security, the protocol contains two strict security checks and accounts for noise, making it robust against both internal and external attacks, which greatly improves the security and reliability of the protocol. Finally, the efficiency analysis demonstrates that the protocol outperforms other existing protocols in terms of efficiency and its actual efficiency can approach the theoretical limit through optimization.
A scheme of using four-qubit cluster state as quantum channel(QC)to convey the quantum state information is proposed to realize two-way communication.In this scenario,two sides of communication,Alice and Bob,share a four-qubit cluster state.In the process of communication,at first,four-qubit cluster state form a whole system with quantum state information two sides have.Then,Alice and Bob perform Bell-state joint measurements to their own part qubits respectively,and tell the measured results to each other via classical channel(CC).Finally,according to the measured results,Alice and Bob make corresponding unitary transformations,hence its own party can reappear the opposite quantum state information.So two-way communication of quantum state information is achieced.