The book "Modeling of functioning of telecommunication systems by Markov processes", written by a team of authors led by Zelentsov B. P. , Melentyev O. G. and by [D.T.]. G. It is a unique study that immerses the reader in the complex but fascinating world of telecommunication systems and methods of their analysis. This publication will become an indispensable assistant for students, graduate students, researchers and practitioners in the field of information technology and telecommunications . The book covers a wide range of topics related to the modeling of telecommunications systems, using Markov processes as the main tool for analysis. The authors consider in detail how these mathematical models can be used to solve real-world problems arising in the design and operation of telecommunications networks. The reader will be able to learn about the different types of Markov processes, their properties and application in the context of communication systems, which makes the material accessible and understandable even for those who are just beginning to get acquainted with this area. One of the key topics of the book is the study of the reliability of telecommunications systems. The authors emphasize the importance of proper modeling to ensure the sustainability and efficiency of networks. With the constant growth in the volume of transmitted information and an increase in the number of users, understanding of the principles of the system becomes especially relevant. The book offers the reader not only theoretical foundations, but also practical examples, which allows you to better absorb the material and apply it in practice. Who can like this edition? First of all, it will be interesting for students and graduate students of technical specialties studying information technologies and telecommunications . The book will also be useful to practicing engineers and specialists working in the field of design and operation of telecommunications systems. Readers interested in mathematical modeling and its application in real problems will find here a lot of useful information and inspiration for their research. The style of the authors is distinguished by clarity and logical presentation, which makes complex concepts more accessible. They use many examples and illustrations, which helps the reader to better understand the material and see its practical application. The book is not only informative, but also fascinating, which makes it easy to immerse yourself in the topic being studied . In addition, it is worth noting that the team of authors includes experienced specialists, each of whom has a significant contribution to the development of telecommunication technologies. For example, a. A. Wolves and P. D. Chelyshkov is known for his research in the field of network technologies and their optimization, and A. In. Sedov is actively engaged in issues of reliability and stability of communication systems. Their joint work in this edition creates a unique synergistic effect, which makes the book especially valuable for the reader. In conclusion, “Modeling the functioning of telecommunication systems by Markov processes” is not just a textbook, but a real find for everyone who seeks to better understand the principles of telecommunication systems and master the methods of their modeling. This publication will become a reliable companion in the world of high technology and will help the reader not only to master theoretical knowledge, but also to develop the practical skills necessary for a successful career in the field of telecommunications.