Chapter Overview

The first computers were stand-alone machines that one person used at a time. Later, timesharing computers were invented that allowed more than one person to use the machine concurrently. When personal computers (PCs) came along, the one computer–one user paradigm came back with a vengeance. But all that is in the past. Today, most computers are networked, i.e., connected to one another so that they can communicate with one another, share resources, and access the Internet. Virtually 100 percent of business and industrial computers are networked. It is estimated that more than 70 percent of all home and personal computers are also networked. This chapter is an introduction to networking and local-area networks (LANs).

Chapter Outline

12-1 Network Fundamentals
12-2 LAN Hardware 455
12-3 Ethernet LANs
12-4 Token-Ring LAN

Chapter Objectives

• Define the terms LAN, MAN, and WAN.
• Explain the basic purposes of LANs and describe some specific LAN applications.
• Draw diagrams of LANs arranged according to the three basic topologies: star, ring, and bus.
• Describe how repeaters, transceivers, hubs, bridges, routers, and gateways are used in LANs.
• Explain the basic difference between client-server and peer-to-peer LANs and give the advantages and disadvantages of each.
• Calculate transmission speed given the length of the data to be transmitted and the characteristics of the LAN over which the data is to be sent.