Quantum method of secure key distribution in optical fiber communication lines

The possibility of using photon counters based on avalanche photodiodes to implement a quantum system for key distribution is shown. The security of encryption key distribution is realized with application of eavesdropper detection technique. The detection technique uses quantum control signal. The structural scheme of the quantum system is presented. The effect of photodetector parameters and the length of optical fiber on the eavesdropper detection time have been determined. The conditions and characteristics of the system to organize a secure channel for generation and transfer of encryption keys over optical fiber communication lines have been determined.