|  |  | Overview

Now that you have a basic understanding of the OSI model and what happens to data packets as they travel through the layers, it is time for you to start looking at basic networking devices. By working through the layers of the OSI reference model, you will learn what devices operate at each layer as data packets travel through them from the source to the destination. The focus of this chapter will be local area network or LAN devices. As you know, LANs are high-speed, low-error data networks that cover a relatively small geographic area (up to a few thousand meters). LANs connect workstations, peripherals, terminals, and other devices in a single building or other geographically limited areas.

In this chapter, you will learn about basic LAN devices and the evolution of networking devices. You will also learn about the networking devices that operate at each layer of the OSI model and how packets flow through each device as they go through the layers of the OSI model. Lastly, you will learn about the basic steps in building LANs. Finally, as you work through this chapter, keep in mind that by interconnecting networking devices, LANs provide multiple connected desktop devices (usually PCs) with access to high-bandwidth media.