Quantum cryptography beyond key exchange

Romain Alléaume

John Rarity, P. R. Tapster, P.M. Gorman

We have designed and built a free space quantum cryptography system. It operates using weak laser pulses with polarization modulation by acousto-optic switching. The system also incorporates full key sifting and error correction between computers connected by a serial port. We have used this system to exchange keys over ranges up to 1.9km with absolute security. The system is robust against transmission (and diffraction) losses up to 20 dB. Building from this initial result we analyse the feasibility of exchanging keys to a low earth orbit satellite.

Charles H. Bennett, Gilles Brassard A

Sreeparna Chakrabarti

The encryption process of Symmetric Key Cryptography is quicker as compared to Asymmetric Key Cryptography, but the key exchange process is a challenge.This paper focuses on Quantum Cryptography techniques for that purpose as traditional digital cryptography techniques are not safe.In "Quantum Key Exchange" Technique, "Heisenberg uncertainty principle" and "quantum no cloning theory" are used to resist attacks.The Quantum Key Exchange is demonstrated through BB84 algorithm and the result is analyzed.Discussion is made on the practical applications of the technique

Rohit Goyal

Quantum cryptography promises secure communication protocols that surpass the limitations of classical cryptography. By leveraging the principles of quantum mechanics, particularly the phenomenon of quantum entanglement and the uncertainty principle, quantum cryptography protocols offer provable security guarantees against eavesdropping attacks. In this paper, we provide an overview of quantum cryptography, discussing its theoretical foundations, key protocols such as quantum key distribution (QKD), and experimental implementations. We highlight the advantages of quantum cryptography over classical cryptographic techniques and explore its potential applications in secure communication networks, financial transactions, and data privacy. Furthermore, we discuss ongoing research efforts and challenges in the practical deployment of quantum cryptography systems, including the development of robust quantum hardware and the integration of quantum cryptographic protocols into existing communication infrastructures. Overall, quantum cryptography holds great promise for enabling secure communication channels that are resilient to quantum attacks, paving the way for a new era of ultra-secure information exchange.