This book by Alexander Breiman is recommended by the Academic Council of MGUPI as a textbook for the specialty 2301 (2201) "Computers, complexes, systems and networks" in global networks, computer networks and telecommunications. The book tells about the organization of composite networks, about TCPIP protocols, about routing in TCPIP networks, protocols and services based on TCPIP, Kh.25 technology, FRAME RELAY, PDH, SDH, ISDN and ATM, about network operating systems, distributed computing technology, application layer protocols (FTP, TFTP, SMTP, POP, IMAP, SSH, Telnet, etc.), as well as about Web technologies.