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Internet Basics

T he simplest definition of the Internet is that it is a collection of local area networks connected together by high-speed public WAN connections. Servers on these LANs provide information to the rest of the Internet in the form of documents, images, and multimedia content. The information delivered by these servers is generally called Internet content . For a small fee, anyone with a computer and a modem can access the Internet and get access to this content. Figure 2.1 shows a graphical representation of the Internet | Internet Basics i-NET OBJECTIVES COVERED IN THIS CHAPTER J Describe a URL its functions and components different types of URLs and use of the appropriate type of URL to access a given type of server. Content may include the following Protocol Address Port S Describe the core components of the current Internet infrastructure and how they relate to each other. Content may include the following Network access points Backbone Identify problems with Internet connectivity from source to destination for various types of servers. Examples could include the following E-mail Slow server Web site J Describe Internet domain names and DNS. Content could include the following DNS entry types Hierarchical structure Role of root domain server Top level or original domains edu com mil net gov org Country level domains UK Copyright 2000 SYBEX Inc. Alameda CA. www.sybex.com TT. he Internet is a very complex entity. To understand the topics found in later chapters in this book you must first understand the underlying layout and technologies of the Internet so that you have a common reference point for those discussions. In this chapter you will learn the following What the Internet is Internet layout Domain Name Services DNS Uniform Resource Locators URLs Internet communications process Throughout this chapter you will also learn the terminology of the devices and processes used on the Internet. Let s begin the discussion of these topics with the definition of the Internet. What Is the Internet The simplest definition of the Internet is that it is a collection of local area networks connected together by high-speed public WAN connections. Servers on these LANs provide information to the rest of the Internet in the form of documents images and multimedia content. The information delivered by these servers is generally called Internet content. For a small fee anyone with a computer and a modem can access the Internet and get access to this content. Figure 2.1 shows a graphical .