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Effective Machine Communication Using Quantum Techniques Provides Improvement in Performance and Privacy through IoT Application
Published in Nishu Gupta, Srinivas Kiran Gottapu, Rakesh Nayak, Anil Kumar Gupta, Mohammad Derawi, Jayden Khakurel, Human-Machine Interaction and IoT Applications for a Smarter World, 2023
Devendar Rao, Ramkumar Jayaraman, Laura Pozueco
The major disadvantage of classical cryptography is the bit can be duplicated, which means ciphertext can be copied and sent to the receiver. Later the cipher can be decrypted to read the information hidden in that encrypted text. In quantum computing, no cloning theorem [19] states that it's impossible to clone or duplicate the unknown quantum states. Let us consider an unknown state |c> = 1√2 (|a>+|b>); adversary wants to apply an auxiliary qubit (|0>) to clone the unknown bit by applying a unitary transformation U. U(|c>0>=12((U|a>0)>+U(b>0>)
Quantum Cryptography and Quantum Key Distribution
Published in Shashi Bhushan, Manoj Kumar, Pramod Kumar, Renjith V. Ravi, Anuj Kumar Singh, Holistic Approach to Quantum Cryptography in Cyber Security, 2023
Chindiyababy, Ramkumar Jayaraman, Manoj Kumar
When we come into quantum cryptography, it is a cryptographic technology that uses quantum physics to protect data resources secure. For example, the trust made by commercial enterprises and banks to hold our credit card details and other information secure while performing online business transactions. Encryption strategy: Can't you ensure the security of personal information? Of course, cybercriminals have been working hard to gain access to protected data, but hackers won't wait for the quantum system to initiate the process because they are collecting our encrypted data to decrypt it when the quantum system is ready. This will not happen when quantum encryption is used, because our data cannot be hacked (Rothe, 2002). Creating copies of unknown quantum states can be prevented by the quantum no-cloning theorem. In quantum computers, the information is stored in the form of qubits instead of classical bits (0s and 1s). Quantum computers are used to handle complex problems. It can be done with the help of the quantum superposition theorem. It states that exactly we don't know the position of an object. Quantum key distribution is used to distribute keys between two endpoints using a sequence of photons through a quantum channel (Wootters et al., 1982). It is the first application to establish secure communication against eavesdropping attacks. This chapter gives an overview of the basic fundamental concepts of quantum cryptography and its various key distribution protocols.
Quantum Computing Application for Satellites and Satellite Image Processing
Published in Thiruselvan Subramanian, Archana Dhyani, Adarsh Kumar, Sukhpal Singh Gill, Artificial Intelligence, Machine Learning and Blockchain in Quantum Satellite, Drone and Network, 2023
Ajay Kumar, B.S. Tewari, Kamal Pandey
The exchange of quantum secret keys among users of a communication network permits users to send and receive messages in a secure manner, free of eavesdropping and data leakage. We are almost invulnerable if we utilise these keys in cryptographic protocols. Because of their computational complexity, traditional cryptosystems rely on algorithms to assure data security. However, because of the so-called Shor’s factoring technique, a quantum computer is capable of cracking even such encryption (Liao et al., 2017). QKD techniques are a solution which uses public optical channels to securely distribute keys by exchanging quantum bits, which are then carried by single photons of light. The no-cloning theorem assures complete security—an eavesdropper’s measurement of a quantum bit risks changing its state. This indicates that the eavesdropper is present. Quantum keys are distributed between two connecting users using photons that travel through optical fibres or through atmospheric line-of-sight channels. We can’t expand quantum communication across oceans due to photon loss in the optical cable. A quantum communication network built on circling satellites, on the other hand, could cover the entire planet’s surface.
Efficient quantum secret sharing based on polarization and orbital angular momentum
Published in Journal of the Chinese Institute of Engineers, 2019
‘Secret sharing’ was first proposed by Shamir (1979). He used the Lagrange interpolation to propose the first practical scheme, in which the secret is split into several parts and distributed to different participants, and such that only the qualified participants can cooperate to recover the initial secret. The concept of ‘quantum secret sharing’ (QSS) was first proposed by Hillery, Buzek, and Berthiaume (1999). They used the Greenberger–Horne–Zeilinger (GHZ) state to design the first QSS scheme. QSS can be seen as the extension of Shamir’s secret sharing into the quantum area. The security of QSS relies on quantum theories such as the uncertainty principle and the no-cloning theorem. QSS can give us an effective way to resist possible attacks from quantum computers in the future.
Quantum-computing with AI & blockchain: modelling, fault tolerance and capacity scheduling
Published in Mathematical and Computer Modelling of Dynamical Systems, 2019
In the future quantum cloud-computing and communication system (see, Figure 2 for a newly designed example), the traditional binary (zero or one) bit based data packets will be replaced by quantum data packets. Each of them will consist of user’s data payload and packet head that indicates the service requirements managed by system software called quantum blockchain in Dai [2] (see, Figure 4 for detail). The length of a quantum data packet is the number of qubits randomly walking over the Bloch sphere as shown in the lower-right graph of Figure 6. Note that, the random step size for each walk along a particular direction over the sphere may be greater than the unity. Furthermore, the packet length is also random from one quantum data packet to another one. However, no matter whether in a quantum computer or in a quantum communication channel, the service time and quality for a quantum data packet depends on the measurement of each single source qubit. Currently, there are numerous physical realizations of quantum computers, which are mainly based on four quantum computing models of practical importance besides the theoretical quantum Turing machine (see, e.g. Deutsch [3], Feynma [4], Nielsen and Chuang [6]). However, the error from the measurement or unitary operation is still the issue. In general, due to the non-cloning theorem (see, e.g. Niestegge [30], Wootters and Zurek [31]), unknown pure quantum states cannot be copied unless they are orthogonal. Nevertheless, according to Niestegge [30] and references therein, the approximate or imperfect cloning of quantum states is possible, e.g. via a generalized non-Gaussian mutual information formula (see, e.g. Dai [23]) by developing a quantum channel between quantum states and their measurements (or their received states) in a probabilistic way. Furthermore, the quantum Zeno effect or called Zeno’s paradox (i.e. the inhibition of transitions between quantum states by frequent measurements, see, e.g. Itano et al. [32], Misra and Sudarshan [33]) is the other concerned issue. Nevertheless, inside the recently realized IBM 50 qubit quantum computer, the quantum coherence time (the time gap to keep a channel stable (i.e. to keep the number of quantum states the same)) can last up to 90 μs to reduce the influence of Zeno effect, which is enough for the quantum computer to perform the required operation and realize one 20-qubit quantum entanglement in 187 ns (see, e.g. the latest announcement in Song et al. [34]). Therefore, with the hope to reduce the error, we develop a quantum channel method in performing the measurement and computation, which is evolved from the one currently being implemented in MIMO wireless channel (see e.g. Dai [2,24]). An example of such a quantum channel is presented in the lower graph of Figure 7 and illustrated via a comparison with an MIMO channel in the upper-left graph of the figure.