Research And Analysis Of Quantum Secret Query Protocol And Image Quantum Encryption Algorithm

Quantum computing is a very popular and rapidly developing field.In the past ten years,significant breakthroughs have been made.As an important research direction of quantum information,quantum cryptography and quantum computing have ushered in new opportunities for the development of information security.Compared with classical cryptography,quantum cryptography has absolute security,ensuring that the key will not be cracked and the security of information transmission.This article further studies the application of quantum based encryption algorithms to images and discovers alternating quantum walking algorithms with nonlinear dynamic characteristics.Quantum walking is the quantum counterpart of classical walking,and as a well-known quantum computing model,quantum walking has been widely used to solve problems in different fields.Due to the high concurrency and nonlinearity of quantum walking,its computational speed can reach exponential levels.Therefore,the application of its quantum computing model in the field of image encryption is also the focus of this study.Firstly,we discuss the quantum secret query technique in the dynamic Bell state authentication.In Chapter 3 of this article,quantum identity authentication was used to prevent the entire process of quantum communication from being invaded by third parties during the use of quantum keys.In this protocol,Bell state and non-decoherence state are used as data transmission media,identity authentication is realized by Bell state entanglement exchange,key distribution is realized by Bell base measurement and asymmetric key is obtained by non-linear operation.As a one-way quantum network protocol,this protocol can effectively combat JM(Joint-Measurement)attacks and reduce the complexity of data transmission,with good security and stability.The impact of thirdparty attacks,JM attacks,user security and communication efficiency on the protocol is analyzed to ensure the security of the information exchanged by the communication parties through this protocol.Secondly,the alternating quantum walk encryption algorithm with nonlinear dynamic characteristics is adopted to apply it in the field of image encryption.Chapter 4of this article proposes an image encryption scheme based on alternating quantum walks and multi-layer knight’s tour to apply to grayscale images.First,I used DCT(Discrete Cosine Transform)to preprocess the initial image in the frequency domain,and I used ML-KST(Multi-Layer Knight’s Tour)to clutter the image in the spatial position.AQW(Alternating Quantum Walks)generates two random key matrices,which act on random phase mask and bitwise XOR respectively.Finally,the encrypted image is obtained by inverse DCT transform.Through experiments,the encryption effectiveness of the scheme is verified.The information entropy value reaches about 7.999,and the space key is large enough to resist various common attacks,so it has good encryption effect.Finally,based on previous research on the alternating quantum walk algorithm,the goal of applying the alternating quantum walk encryption algorithm to the field of color images was achieved.Chapter 5 of this article proposes a hybrid AES color image encryption algorithm that combines alternating quantum walk and discrete cosine transform.Using alternating quantum walk to improve the key expansion function of traditional AES,it makes full use of the chaos and unpredictability of AQW,and combines the decorrelation and energy concentration characteristics of DCT to enhance the security and anti-attack ability of AES algorithm in the process of image encryption,and has achieved good results.Compared with other encryption schemes,this scheme has better key security and encryption effect.This paper mainly includes three parts of innovation: First,a quantum secret query protocol based on Bell state identity authentication is proposed;Second,an image encryption scheme based on Alternate Quantum Walks(AQW)and Multi-layer Knight’s Tour(ML-KST)is proposed for grayscale images;Thirdly,an image encryption algorithm based on improved AES(Advanced Encryption Standard)algorithm and alternating quantum walk is proposed for color images.