The quantum communication,based on the principle of quantum mechanics,could directly transmit secret information over the quantum channel,and could realize high security and high capacity.QSDC(Quantum Secure Direct Communication),as a new kind of quantum communication,could securely transtmit secret information directly over the quantum channel.QSDC has acquired fast development since proposed nearly ten years ago.Some typical quantum direct communication protocols or models adopted by QSDC are described in this paper,including entangled photo pairs-based two-step QSDC protocol and high dimensional quantum-based communication protocol.Meanwhile the development trend of QSDC is also briefed.
The quantum communication,based on the principle of quantum mechanics,could directly transmit secret information over the quantum channel,and could realize high security and high capacity.QSDC(Quantum Secure Direct Communication),as a new kind of quantum communication,could securely transtmit secret information directly over the quantum channel.QSDC has acquired fast development since proposed nearly ten years ago.Some typical quantum direct communication protocols or models adopted by QSDC are described in this paper,including entangled photo pairs-based two-step QSDC protocol and high dimensional quantum-based communication protocol.Meanwhile the development trend of QSDC is also briefed.
Quantum communication exploits the principles of quantum mechanics in the transmision and processing of information. It has the advantages of high security and high capacity. Quantum secure direct communication (QSDC) is a new mode of quantum coomunication by Long and Liu in which secret information can be transmitted securely and directly over quantum channels. Since it was first proposed in 2000, QSDC has been developed very fast. In this review, we will explain the basic principles of QSDC and describe some typical QSDC protocols. Toward the end of the review, we will introduce the new trends in the QSDC research and give a perspectiv of QSDC research.
Quantum secure direct communication (QSDC) is a new type quantum communication scheme based on quantum mechanics, which can transmit deterministic information and is more close to classical communication compared with earlier quantum key distribution (QKD) schemes which require auxiliary pre-distribution of secret key, and has become an important branch of quantum communication in recent years. A comprehensive review is presented about the present development of QSDC, with typical QSDC schemes based on various quantum principles as well as the comparisons between them. Then the experimental research on QSDC is reviewed briefly and the future direction is prospected in the end.
Quantum secure direct communication (QSDC) is one of the most important branches of quantum communication. In contrast to the quantum key distribution (QKD) which distributes a secure key between distant parties, QSDC directly transmits secret message instead of sharing key in advance. To establish a secure QSDC protocol, on the one hand, the security of the quantum channel should be confirmed before the exchange of the secret message. On the other hand, the quantum state should be transmitted in a quantum data block since the security of QSDC is based on the error rate analysis in the theories on statistics. Compared with the deterministic quantum key distribution (DQKD) which can also be used to transmit deterministic information, QSDC schemes do not need extra classical bits to read the secret message except for public discussion. In this article, we introduce the basic principles of QSDC and review the development in this field by introducing typical QSDC protocols chronologically. The first QSDC protocol was proposed by Long and Liu, which can be used to establish a common key between distant parties. In their scheme, the method for transmitting quantum states in a block by block way and in multiple steps was proposed and the information leakage before eavesdropping detection was solved. Subsequently, Deng et al. presented two pioneering QSDC schemes, an entangled-state-based two-step QSDC scheme and a single-photon-state-based quantum one-time pad scheme, in which the basic principle and criteria for QSDC were pointed out. From then on, many interesting QSDC schemes have been proposed, including the high-dimension QSDC scheme based on quantum superdense coding, multi-step QSDC scheme based on Greenberger-Horne-Zeilinger states, QSDC scheme based on quantum encryption with practical non-maximally entangled quantum channel, and so on. We also introduce the anti-noise QSDC schemes which were designed for coping with the collective-dephasing noise and the collective-rotation noise, respectively. In 2011, Wang et al. presented the first QSDC which exploited the hyperentangled state as the information carrier and several QSDC schemes based on the spatial degree of freedom (DOF) of photon, single-photon multi-DOF state and hyperentanglement were proposed subsequently. In addition to the point-to-point QSDC schemes, we also review the QSDC networks. Finally, a perspective of QSDC research is given in the last section.
Quantum secure direct communication (QSDC) transmits information securely through a quantum channel, distinct among various quantum communications. Proposed by me and Liu 20 years ago, QSDC has now been developed to a stage that is ready for practical application. QSDC advances classical communication of reliable communication over a noisy channel, which is guaranteed by Shannon's theory, to a higher plane of both secure and reliable communication over a noisy channel even in the presence of eavesdropping. Here we briefly introduce the basic principles, the techniques for practical applications.
Quantum security direct communication is based on quantum physics, combined with the classic communication theory.It becomes a new communication model, its transmission of information on the high efficiency, security has been more and more extensive attention.That is, since the beginning of this century, has been rapid developed.In this paper, we will describe several common quantum secure direct communication protocols and economic quantum secure direct communication network models theoretically.At the end of this paper, we will discuss and analyze the development and the future of quantum safety direct communication. Quantum Direct Communication Protocol Two-Step QSDC Protocol. The two-Step QSDC protocol uses the protocol of the entangled particle pair and the single-photon sequence. The following is a schematic diagram of the Two-Step
Quantum key distribution (QKD) is considered as an ideal method to make secret message unreadable to eaves-dropper but intelligible to the two authorized parties of the communication [1][2][3][4][5][6].In the research of experimental quantum key distribution, single photons and entangled photon pairs are used as the carriers.In quantum key distribution, secret keys are generated first between the communication parties.The security of quantum key distribution is guaranteed by the laws of quantum mechanics.After the quantum key distribution is completed, the communication parties should share secret keys, then the sender encrypts the secret message using the secret keys to form the ciphertext and transmits the ciphertext through a classical channel.The receiver receives the ciphertext and then decrypt the ciphertext to get the secret message.Altogether there are four steps in a secret communication process with QKD: key generation, encryption, transmission and decryption.Here in this review, we review some new development in quantum communication, quantum direct communication (QDC).Quantum direct communication is a form of quantum communication where secret messages can be transmitted through a quantum channel with or without additional classical communications.There are two forms of quantum direct communication, quantum secure direct communication (QSDC) [7{9] and deterministic secure quantum communication (DSQC) [10,11].In QSDC, secret messages are transmitted directly between the communication parties, from sender Alice to receiver Bob, without additional classical communication except those for the necessary eavesdropping check.In other words, the quantum key distribution process and the classical communication of ciphertext are condensed into one single quantum communication procedure in QSDC.Deterministic secure quantum communication is another type of quantum direct communication, such as those proposed in Ref. [10,11], where classical communication is required in order to read out the secret message.As mentioned earlier, to complete a secure communication with the help of QKD, one usually encodes the secret message with an encryption scheme, and the ciphered text is transmitted through a classical channel.With a quantum channel, this procedure can be varied.