An efficient quantum secure direct communication scheme with authentication

In this paper an efficient quantum secure direct communication （QSDC） scheme with authentication is presented, which is based on quantum entanglement and polarized single photons. The present protocol uses Einstein-Podolsky-Rosen （EPR） pairs and polarized single photons in batches. A particle of the EPR pairs is retained in the sender＇s station, and the other is transmitted forth and back between the sender and the receiver, similar to the‘ping-pong＇ QSDC protocol. According to the shared information beforehand, these two kinds of quantum states are mixed and then transmitted via a quantum channel. The EPR pairs are used to transmit secret messages and the polarized single photons used for authentication and eavesdropping check. Consequently, because of the dual contributions of the polarized single photons, no classical information is needed. The intrinsic efficiency and total efficiency are both 1 in this scheme as almost all of the instances are useful and each EPR pair can be used to carry two bits of information.

Quantum Secure Direct Communication with Authentication Expansion Using Single Photons

In this paper we propose two quantum secure direct communication (QSDC) protocols with authentication.The authentication key expansion method is introduced to improve the life of the keys with security.In the first scheme,the third party, called Trent is introduced to authenticate the users that participate in the communication.He sends thepolarized photons in blocks to authenticate communication parties Alice and Bob using the authentication keys.In thecommunication process, polarized single photons are used to serve as the carriers, which transmit the secret messagesdirectly.The second QSDC process with authentication between two parties is also discussed.

Controlled mutual quantum entity authentication using entanglement swapping

In this paper, we suggest a controlled mutual quantum entity authentication protocol by which two users mutually certify each other on a quantum network using a sequence of Greenberger–Horne–Zeilinger（GHZ）-like states. Unlike existing unidirectional quantum entity authentication, our protocol enables mutual quantum entity authentication utilizing entanglement swapping; moreover, it allows the managing trusted center（TC） or trusted third party（TTP） to effectively control the certification of two users using the nature of the GHZ-like state. We will also analyze the security of the protocol and quantum channel.

Quantum Authentication Based on the Lengthened String Scheme

Assuming there is a shared string between the users, we present a novel scheme, the lengthened string scheme (LSS), where the shared string is lengthened firstly by a specially designed algorithm, then some special treatments are applied on the lengthened one before it is used to authenticate. Based on the lengthened string scheme (LSS) we propose a quantum authentication protocol using entanglements. And the robustness of our protocol is discussed. In fact all the quantum key distribution protocols can do identification simultaneously based on the LSS.

Economical multiparty simultaneous quantum identity authentication based on Greenberger-Horne-Zeilinger states

A multiparty simultaneous quantum identity authentication protocol based on Creenberger-Horne-Zeilinger （GHZ） states is proposed. The multi-user can be authenticated by a trusted third party （TTP） simultaneously. Compared with the scheme proposed recently （Wang et al 2006 Chin. Phys. Lett. 23（9） 2360）, the proposed scheme has the advantages of consuming fewer quantum and classical resources and lessening the difficulty and intensity of necessary operations.

High-Capacity Quantum Secure Communication with Authentication Using Einstein-Podolsky-Rosen Pairs

A new protocol for quantum secure communication with authentication is proposed. The proposed protocol has a higher capacity as each EPR pair can carry four classical bits by the XOR operation and an auxiliary photon. Tile security and efficiency are analyzed in detail and the major advantage of this protocol is that it is more efficient without losing security.

One-Way Quantum Authenticated Secure Communication Using Rotation Operation

This study proposes a theoretical quantum authenticated secure communication(QASC) protocol using Einstein-Podolsky-Rosen(EPR) entangle state,which enables a sender to send a secure as well as authenticated message to a receiver within only one step quantum transmission without having the classical channels and the certification authority.

Efficient and Secure Authenticated Quantum Dialogue Protocols over Collective-Noise Channels

Based on the deterministic secure quantum communication, we present a novel quantum dialogue protocol with- out information leakage over the collective noise channel. The logical qubits and four-qubit decoherence-free states are introduced for resisting against collective-dephasing noise, collective-rotation noise and all kinds of unitary collective noise, respectively. Compared with the existing similar protocols, the analyses on security and information-theoretical emciency show that the proposed protocol is more secure and emeient.

Robust general N User authentication scheme in a centralized quantum communication network via generalized G HZ states

Quantum communication provides an enormous advantage over its classical counterpart： security of communications based on the very principles of quantum mechanics. Researchers have proposed several approaches for user identity authentication via entanglement. Unfortunately, these protocols fail because an attacker can capture some of the particles in a transmitted sequence and send what is left to the receiver through a quantum channel. Subsequently, the attacker can restore some of the confidential messages, giving rise to the possibility of information leakage. Here we present a new robust General N user authentication protocol based on N-particle Greenberger-Horne-Zeilinger （GHZ） states, which makes eavesdropping detection more effective and secure, as compared to some current authentication protocols. The security analysis of our protocol for various kinds of attacks verifies that it is unconditionally secure, and that an attacker will not obtain any information about the transmitted key. Moreover, as the number of transferred key bits N becomes larger, while the number of users for transmitting the information is increased, the probability of effectively obtaining the transmitted authentication keys is reduced to zero.

Cryptanalysis of Controlled Mutual Quantum Entity Authentication Using Entanglement Swapping

By using GHZ-like states and entanglement swapping, Kang et al. [Chin. Phys. B 24(2015) 090306]proposed a controlled mutual quantum entity authentication protocol. We find that the proposed protocol is not secure,that is, the center, Charlie can eavesdrop the secret keys shared between Alice and Bob without being detected.

Quantum Key Distribution Based on Entangled States and Non-Orthogonal States

In this paper two Quantum Key Distribution(QKD)protocols are proposed,which combined BB84 protocoland EPR protocol subtly.In our protocols,entangled particles and non-orthogonal particles are mixed together and trans-mitted in the quantum channel.They play different roles respectively,and their physical characters are fully exploited.As a result,the efficiency of QKD is improved and identity authentication is added to the QKD procedure.