The work program set forth in this manual is part of the main professional educational program in accordance with the Federal State Educational Standard for the specialty of open source software "Computer Networks" (basic training) in terms of mastering the main type of professional activity "Network Infrastructure Design" and relevant professional competencies. The textbook is drawn up in accordance with the working program and is intended for students of the special software specialty "Computer Networks" when studying the PM.01 "Network Infrastructure Design," and can also be used in additional vocational education and training of workers in areas related to the maintenance of computer networks, in the presence of secondary (full) education.