Cisco Systems is one of the world leaders in the development and production of network equipment She pays great attention to training specialists in setting up and configuration of her equipment. Thanks to the extensive network of local Cisco academies, as well as extensive information support in the form of books, brochures, presentations, etc. d. The company provides training of a significant number of necessary specialists. However, in our country, the picture is not so rosy . The remoteness of many engineers from information and educational centers, even in the presence of the Internet, forces them to fill gaps in knowledge on their own with the help of existing books and textbooks. Unfortunately, translations of books by foreign authors into Russian may contain inaccuracies. In addition, issues related to the principle of operation and configuration of switches are considered in some books, and routers in others. Therefore, a person who has decided to independently master the administration of Cisco corporate networks is forced to look for answers in large volumes of books. This prompted the author - Alexander Ermakov to write a training manual "Basics of configuration of Cisco corporate networks" in a short and accessible form to present theoretical information about the functioning of network equipment and give practical recommendations on its configuration. It is assumed that the reader is familiar with network technologies and Ethernet architecture. This edition is recommended by the Expert Council for Review of the Moscow State University of Railways, authorized by the order of the Ministry of Education and Science of Russia dated January 15, 2007. No. 10, to be used as a teaching aid for students studying in the direction of training 230700. 62 "Applied Informatics" in PO. The book can also be useful to engineering workers associated with the operation and configuration of Cisco equipment. In the book "Basics of configuration of corporate networks Cisco" tells about OSI, DoD, Cisco Hierarchical Model , TCP/IP, Transport Layer IP Addresses and Addresses, VLAN, STP, Routing, Traffic Filtering , IOS operating system, Cisco Switches and Routers and more.