ITT Technical Institute
Introduction to Networking NT1210 October 28, 2013
The chapter starts out explaining how a BN (Backbone Network) works.
Backbone Network: Connecting all of the LANs of an organization entails another type of network (BN). A properly designed backbone network provides a high-speed circuit that serves as the central conduit across which the LANs of an organization can communicate. They can also be used to connect LANs within a building, across a campus, and, increasingly, across much greater distances. A BN, as indicated by its name, is a network of its own. Besides connecting the various network segments, the backbone may have its own devices that can be accessed by other network segments Metropolitan area network (MAN): MAN spans a city and is often used to connect remote BNs. MAN in some cases can be considered a citywide BN and as the geographic distances they cover have increased, especially with the use of fiber-optics. BNs connect networks between floors of a building, across a city, or between states and countries. BN and MAN are sometimes used interchangeably, based on the scope of the BN. Network Segments: Each individual LAN owned by an organization is reffered to as a network segment.
Horizontal Segment: A moderate- to large-scale organization might have a network segment on each floor of a multistory building. Because each network segment, or LAN, typically occupies its own floor, this type of network segment is often referred to as a horizontal network. For example, assume that a business occupies three floors of a building. On each floor is a separate LAN, or horizontal network segment. Vertical Network: LANs could, and probably would, be connected to each other by a BN. This type of multi-floor connection is an example of a vertical network. The BN in this instance is the central