Quantum cryptography-the application of quantum information processing and quantum computing techniques to cryptography has been extensively investigated. Two major directions of quantum cryptography are quantum key distribution (QKD) and quantum encryption, with the former focusing on secure key distribution and the latter focusing on encryption using quantum algorithms. In contrast to the success of the QKD, the development of quantum encryption algorithms is limited to designs of mostly one-time pads (OTP) that are unsuitable for most communication needs. In this work we propose a non-OTP quantum encryption design utilizing a quantum state creation process to encrypt messages. As essentially a non-OTP quantum block cipher the method stands out against existing methods with the following features: 1. complex key-ciphertext relation (i.e. confusion) and complex plaintext-ciphertext relation (i.e. diffusion); 2. mode of operation design for practical encryption on multiple blocks. These features provide key reusability and protection against eavesdropping and standard cryptanalytic attacks.
Quantum cryptography-the application of quantum information processing and quantum computing techniques to cryptography has been extensively investigated. Two major directions of quantum cryptography are quantum key distribution (QKD) and quantum encryption, with the former focusing on secure key distribution and the latter focusing on encryption using quantum algorithms. In contrast to the success of the QKD, the development of quantum encryption algorithms is limited to designs of mostly one-time pads (OTP) that are unsuitable for most communication needs. In this work we propose a non-OTP quantum encryption design utilizing a quantum state creation process to encrypt messages. As essentially a non-OTP quantum block cipher the method stands out against existing methods with the following features: 1. complex key-ciphertext relation (i.e. confusion) and complex plaintext-ciphertext relation (i.e. diffusion); 2. mode of operation design for practical encryption on multiple blocks. These features provide key reusability and protection against eavesdropping and standard cryptanalytic attacks.
Quantum communication is an important application that derives from the burgeoning field of quantum information and quantum computation.Focusing on secure communication, quantum cryptography has two major directions of development, namely quantum key distribution and quantum encryption.In this work we propose a quantum encryption protocol that utilizes a quantum algorithm to create blocks of ciphertexts based on quantum states.The main feature of our quantum encryption protocol is that the encryption configuration of each block is determined by the previous blocks, such that additional security is provided.We then demonstrate our method by an example model encrypting the English alphabet, with numerical simulation results showing the large error rate of a mock attack by a potential adversary.The safety of the encryption method is further demonstrated against several possible attack models.With the improvements against noises, our quantum encryption protocol is a capable addition to the toolbox of quantum cryptography.
Cryptography is the process of encrypting data or transforming plain text to ciphertext so that it can be deciphered only by appropriate key. Quantum cryptography employs quantum physics principles to encrypt and transport data in an unpackable manner. Quantum key distribution (QKD) is a technique for creating and exchanging private keys over quantum channels between two parties. Then, using standard cryptography, the keys can be used to encrypt and decrypt messages. Unbreakable encryption is something we really must have. The integrity of encrypted data is now in danger due to the impending development of quantum computers. Fortunately, quantum cryptography, via QKD, provides the answer we require to protect our information for a very long time to come. This is all based on the intricate principles of quantum mechanics. This chapter is discussing the various algorithms used and the applications of quantum cryptography.
Data protection and information security have been the essence of communication in today's digital era. Authentication and secrecy of secure communication are achieved using key-based cryptographic primitives; the security of which significantly relies upon the underlying computationally complex mathematics. Moreover, these existing cryptographic primitives are considered to be non-deterministic on the basis of the existing computational capabilities. However, the considerable advancements in the development of quantum computers have significantly enhanced parallel computations; thereby, posing a great threat to these existing encryption primitives. Thus, in the future, the physical manifestation of a large successful quantum computer is likely to break all the existing public-key encryption algorithms in no time. This has led to a remarkable surge of interest in propelling quantum mechanics into existence; subsequently, leading cryptographers to research various viable domains to offer quantum-resistant secure communications. Resultantly, quantum cryptography/quantum key distribution has emerged as a futuristic replacement for classical cryptography as it offers unconditionally secure communication along with the inherent detection of any unintended user. Thus, keeping in view the significance of this relatively newer domain of cryptography, this research focuses on presenting a consolidated review of the various Quantum Key Distribution (QKD) protocols. A comparative analysis of the working mechanism of the prominent QKD protocols is presented along with an overview of the various emerging trends that have been proposed to optimize the implementational efficiency of the BB84 protocol.
Security knowledge is one of the foremost challenges in the present day. When the topic is about Information security, the concept of cryptography comes into the picture. Every day, people and organizations use cryptography to maintain the confidentiality of their communications and data as well as to preserve their privacy. Today, one of the most successful methods used by businesses to protect their storage systems, whether at rest or in transit, is cryptography. Yet, cryptography is an effective technique to secure the data, the modern technology can break the cryptographic techniques. But some data encryption algorithms are several times stronger than today's conventional cryptography and can be constructed using quantum computing. They are "Quantum Cryptographic Algorithms ". Quantum cryptography uses the rules of quantum physics instead of classical encryption, which is based on mathematics, to protect and transmit data in a way that cannot be intercepted. Quantum key distribution is the greatest illustration of quantum cryptography and offers a safe solution to the key exchange issue. The proposed work deals with quantum cryptography and mainly focuses on how the quantum cryptographic algorithm is more secure than traditional cryptography.
So far, quantum key distribution (QKD) has been the main subject in the field of quantum cryptography, but that is not quantum cryptographic communication, it is only the ability to send keys for cryptographic purposes. To complete cryptographic communication, a technique for encrypting data is necessary, and the conventional cryptographic technique of mathematical symmetric key cipher or One Time Pad (OTP) is adopted in the discussion so far. However, OTP is not the ultimate cipher for data encryption, because it does not satisfy security conditions in the modern cryptology. Around 2000, a new quantum stream cipher was proposed as a technique to challenge the possibility of overcoming drawbacks of OTP in practical use. Recently, we have published some review papers on it in Entropy (Open access journal), and others. This paper introduces an overview and a back ground of our paper that is entitled Quantum stream cipher based on Holevo-Yuen theory.
Quantum key distribution is an innovative technique to distribute encryption keys without compromise. This paper focuses on the application of this technique to achieve reliable communication in an ever-evolving and increasingly vulnerable environment. Designers of cryptosystems have three basic objectives; designing cryptographic algorithms that adequately scramble the target data, developing strong encryption keys to lock and unlock the algorithm, and securely distributing the keys between communicating devices. The advance of quantum computing technologies threatens to expose the world's most prolific key method overnight. Though quantum computing is not yet a reality, the basic principles have been proven in laboratories. Furthermore, quantum computing has been shown to be especially suited for computations of complex mathematic equations; such as distilling the private keys from the public keys used in public key infrastructures (PKI). In this environment, it's comforting to know that the most advanced technology in the broad field of quantum communications just happens to be a new method of creating and distributing encryption keys. This technology is referred to as quantum key distribution (QKD). QKD technologies shift the current paradigm on two plains. The first is that it uses quantum principles, rather than conventional means, for distributing keys between devices. The quantum principles guarantee the key can not be intercepted during transmission without alerting the users of a compromise. The second shift is derived from the fact that encrypted data can not be intercepted today and decrypted at a later date when the computing power exists to crack the code. This shift is dependant on the use of a combination of QKD and one-time pad. Because of the quantum principles that QKD relies on, when a key is successfully created and shared, it can not be cracked using intercepted data. The keys are derived from a convergence of random operations conducted at the sender and receiver stations. Indeed, neither the sender nor the receiver can determine what the key will be until the entire process is completed. As a piece of our security infrastructure, QKD significantly raises our security posture. This paper explains the application of quantum principals used to enable QKD systems.