Quantum cryptoyraphy: The concept and challenyes

This Quantum cryptoyraphy is one of the emeryiny topics in the field of computer industry. This paper focus on quantum cryptoyraphy and how this technoloyy contributes value to a defense-in-depth strateyy pertaininy to completely secure key distribution. The scope of this paper covers the technical challenyes to implement the concepts of quantum cryptoyraphy. We describe the quantum key distribution by which two users who share no secret information (without haviny any private or public keys known before hand) initially exchanye a random quantum transmission consistiny of very faint flashes of polarized liyht. We are focusiny on practical quantum key distribution, takiny into account channel losses, a realistic detection process, and imperfections in the “qubits” sent from the sender to the receiver. As we show, even quantum key distribution with perfect qubits miyht not be achievable over lony distances when the other imperfections are taken into account. ??