The textbook describes the principles of time separation of channels, the basics of digital information transmission technologies, general requirements for the primary digital network, and the principles of constructing digital transmission systems (DSPs) of the plesiochronous digital hierarchy (PDH). The features of constructing a synchronous digital hierarchy (SDH), issues of constructing linear paths of digital transmission systems over metal and optical cables are considered, and methods for calculating the quality indicators of channels and paths are given. Functional methods for protecting digital streams and managing digital SDH networks are described. The features of the DSP application in railway transport, design and technical operation of the primary transport communication network based on the DSP are considered.
It is intended for students of technical schools studying in the specialty 210407 "Operation of communication facilities", colleges, and can also be useful for students of technical universities studying automation, telemechanics and communication in railway transport (specialization "Information transmission and distribution systems").