Introduction to Networking
Welcome to the world of computer networking. As you begin your study, it is important that you understand some of the fundamental concepts upon which computer networks are built. This chapter introduces you to these concepts. What Is a Network?
This lesson introduces some basic principles of computer-based networking, discusses advantages of networking, and presents the idea of connecting computers together to form a local area network (such as a corporate intranet) and a wide area network (such as the Internet). After this lesson, you will be able to:
* Define a computer network.
* Discuss advantages of using a network.
* Describe a local area network (LAN) and a wide area network (WAN). * Identify the primary difference between a LAN and a WAN. The Concept of Networking
The idea of networking has been around for a long time and has taken on many meanings. If you were to look up "network" in your dictionary, you might find any of the following definitions: * An openwork fabric; netting
* A system of interlacing lines, tracks, or channels
* Any interconnected system; for example, a television-broadcasting network * A system in which a number of independent computers are linked together to share data and peripherals, such as hard disks and printers Obviously, the last definition is the one we are concerned with in this course. The key word in the definition is "share." Sharing is the purpose of computer networking. The ability to share information efficiently is what gives computer networking its power and its appeal. And when it comes to sharing information, human beings are in many ways similar to computers. Just as computers are little more than collections of the information they have been given, so we are, in large part, collections of our experiences and the information given to us. When we want to expand our knowledge, we broaden our experience and gather more information. For example, to learn more about computers, we might talk informally with friends in the computer industry, go back to school and take a class, or work through a self-paced training course like this one. Whichever options we choose, when we seek to share the knowledge and experiences of others, we are networking. Another way to think of networking is to envision a network as a team. This might be a sports team, such as a football team, or a project team, such as the one that created this training course. Through the efforts of all involved—the sharing of time, talent, and resources—a goal is accomplished or a project is completed. Similarly, managing a computer network is not unlike managing a team of people. Sharing and communicating can be simple and easy (a quarterback calling a play in the huddle) or complex (a virtual project team located in different time zones around the world that communicates through teleconferencing, e-mail, and multimedia presentations over the Internet to complete a project). Introducing Computer Networking
At its most elementary level, a computer network consists of two computers connected to each other by a cable that allows them to share data. All computer networking, no matter how sophisticated, stems from that simple system. While the idea of connecting two computers by a cable may not seem extraordinary, in retrospect it has proven to be a major achievement in communications. Computer networking arose as an answer to the need to share data in a timely fashion. Personal computers are powerful tools that can process and manipulate large amounts of data quickly, but they do not allow users to share that data efficiently. Before networks, users needed either to print out documents or copy document files to a disk for others to edit or use them. If others made changes to the document, there was no easy way to merge the changes. This was, and still is, known as "working in a stand-alone environment." (See Figure...