Overview

In this chapter we present the basic definitions of several terms related to computer networks. Understanding these definitions is critical because they serve as the foundation of our study of networks and will be used and expanded upon in subsequent chapters. An outline of the terms and concepts defined and discussed follows:

• Computer Networks (Questions 1 12)
• Applications vs. Application Protocols (Questions 13 17)
• Interoperability (Questions 18 19)
• Internet, internet (Internetwork), Intranet, Extranet (Questions 20 22)
• LAN, MAN, WAN, PAN, GAN, SAN (Questions 23 24)
• Decentralized vs. Centralized vs. Distributed Systems (Questions 25 27)
• Network Computers (NC) (Questions 28 29)
• Network Operating Systems (NOS) (Question 30)
• Client/Server vs. Peer-to-Peer (Questions 31 36)
• Serial vs. Parallel Communications (Questions 37 40)
• Synchronous vs. Asynchronous Communications (Questions 41 44)
• Simplex vs. Half-Duplex vs. Full-Duplex Communications (Questions 45 46)
• Network Standards (Questions 47 54)

1. What is a computer network?

   A computer network is a collection of computers and other devices that use a common network protocol to share resources with each other over a network medium.

2. That's a mouthful. Can you break this down for me, please? There are several terms I do not understand.

   Sure. Where do you want to start?

3. First of all, you say a computer network is a collection of computers and other devices. What other devices?

   In our definition we use the term device to represent any entity that is connected to a network. Such entities may be terminals, printers, computers, or special network-related hardware units such as communication servers, repeaters, bridges, switches, routers, and various other devices,...