Quantum cryptography

The bachelor thesis focuses on quantum cryptography. In the theoretical part, there is an analysis of secure key distribution in the fiber-optic infrastructure. Methods such as quantum key distribution (QKD) or physical layer secret key generation for fiber-optic networks are analyzed, including a description of the security and technical limitations of the methods. The thesis also attempts to interpret some basic principles of the optic infrastructure used in QKD. In addition to the distribution of keys, the thesis also tries to approximate the basic principles of the optic infrastructure used in QKD and, last but not least, post-quantum cryptography (including a comparison with quantum cryptography and current protocols). In the practical part, the effect of the macrobending of the fiber and the reflectivity of the connectors on the operation of the quantum system was demonstrated. It was also demonstrated that temperature and light acting on the QKD optic infrastructure do not have a fundamental effect