In the late twentieth century, human race entered the era of information technology (IT). The IT industry, which deals with the production, processing, storage and transmission of information, has become an integral part of the global economic system, a completely independent and significant sector of the economy. The dependence of the modern society on information technologies is so great that omissions in information systems may lead to significant incidents. Telecommunications are the key information technology industry. However, information is very susceptible to various types of abuse during transmission. The units for data storage and processing can be physically protected from anyone wishing harm, but this does not hold true for the communication lines that span hundreds or thousands of kilometers and are virtually impossible to protect. Therefore, the problem of information protection in the field of telecommunications is highly significant. Cryptology, particularly cryptography, deals with this issue. Quantum cryptography is a relatively new field ensuring safe communication between the sender and the recipient using the laws of quantum physics. This paper seeks to address the principles of the quantum distribution of a key for information encryption and the fundamental problems arising from the execution.