The Internet & the World Wide Web

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Chapter 2

The Internet & the World Wide Web

Brief Chapter Outline

Section 2.1 – Connecting to the Internet: Narrowband, Broadband, & Access Providers

This section discusses both wired and wireless means of connecting to the internet.

Section 2.2 - How Does the Internet Work?

This section discusses basic structure of the internet and who controls it.

Section 2.3 – The World Wide Web

This section discusses the various components of the web and how they work.

Section 2.4 – Email & Other Ways of Communicating over the Net

This section discusses email & webmail, as well as instant messaging, FTP, newgroups, and other ways of communication over the internet.

Section 2.5 – The Online Gold Mine: Telephony, Multimedia, Webcasting, Blogs, E-Commerce, & Other resources

This section discusses many of the activities and services offered by the internet and the web.

Section 2.6 - The Intrusive Internet: Snooping, Spamming, Spoofing, Phishing, Pharming, Cookies, & Spyware

This section discusses the problems and dangers associated with using the internet and the web.

Lecture Outline

Teaching Tip

Ask students for questions and concerns at the beginning of the class and compile a list of these questions to refer to. Answer all the questions during the class and check them off the list once they have been answered. Make a new list at the beginning of each new chapter.

2.1. Connecting to the Internet: Narrowband, Broadband, & Access Providers

Key Question: What are the means of connecting to the internet, and how fast are they? What are the three kinds of internet provider?

Bandwidth, or channel capacity, is an expression of how much data—text, voice, video, and so on—can be sent through a communications channel in a given amount of time.

Baseband transmissions allow only one signal at a time to be transmitted; broadband transmissions are very high-speed connections that carry more than one signal at a time.

A. Physical connection

The wired or wireless means of connecting to the internet. Choices include telephone wires (dialup via modem); ISDN; DSL; T1; cable modem; satellite and other wireless means.

B. Data transmission speeds

Data is transmitted in characters or collections of bits. Bit = smallest unit of data/information used by computers. Speeds are measured in bits, kilobits, megabits, and gigabits per second.

1.Bps stands for bits per second. A computer with an older modem might have a speed of 28,800 bps per second.

2.Kbps stands for kilobits per second, or 1,000 bits per second. 28,800 bps = 28.8 Kbps.

3.Mbps stands for megabits per second—1 million bits per second.

4.Gbps stands for gigabits per second—1 billion bits per second.

Additional Information

Here’s a table from Option Telecom ( that shows how quickly a 1-MB file can be transmitted via various bandwidths.

C. Uploading & downloading

Download and upload refer to the transfer of information between computers. Upload = transmit data from a local computer to a remote computer; download = transmit data from a remote computer to a local computer. The person/computer sending the information refers to the transfer as an upload, while the person/computer receiving the information refers to it as a download.

Most people use the term download when they are receiving a file, and upload when they are sending a file over the Internet.

Additional Information

The act of transferring a file from one web server to another, while technically a simultaneous download and upload, is often called sideloading.

Web Exercise

This website gives a detailed tutorial on different methods to access the internet:

D. Narrowband (dial-up modem)

The telephone line is still the cheapest and most widely available means of internet connection. It is a narrowband (low bandwidth) connection. Telephone connections are dial-up connections that use a telephone modem.

1.Modem: device that sends and receives data over telephone lines to and from computers. Standard telephone modems have a maximum speed of 56 Kbps.

Additional Information

Telephone modems are often called analog modems to differentiate them from high-speed DSL and cable modems. Essentially, analog modems speeds are limited to 56 Kbps because of the nature of telephone lines and the “noise" that occurs on them. The terms analog and digital are discussed in detail in Chapter 14, and modems are discussed in more detail in Chapter 6.

Users’ modems work with the modems of their internet access providers (ISPs), the regional, national, or wireless organization / business that connects them to the internet.

2.Call waiting: When one is connected to the internet via a telephone modem, telephone calls will not come through, and call waiting will not work. Many users get a second, dedicated phone number to use just for the modem.

E. High-Speed Phone Lines

The regular phone system is called POTS, plain old telephone system. Faster but more expensive connections are available in most cities.

1. Integrated Services Digital Network (ISDN) line = hardware and software that allow voice, video, and data to be communicated over traditional copper-wire telephone lines. ISDN users make arrangements with their telephone company to have an adapter installed on their computers.

2. Digital Subscriber Line (DSL) uses regular phone lines, a DSL modem, and special technology to transmit data in megabits per second.

3. T1 line is a dedicated digital trunk line that carries 24 normal telephone circuits and has a transmission rate of 1.5 Mbps. (T2 and T3 lines are even faster.)

Group Exercise

Ask the students to list all of the services and products they can think of that are available today because of the internet.

For example:
Email
Automated bill payment
Chat rooms
E-commerce
Online shopping
Downloaded music and movies
Books online
Education, courses online
Newspapers online
Magazines online
Phone calls via internet
Stock purchase/investing
Games
Auction

Group Exercise

Ask students to search the web and find common applications of the following methods of connection:

ISDN
DSL
Cable modem
T1 line

Also have them find information on how T2 and T3 lines are used.

Additional Information

Get information about speeding up modem connections at

discusses “tweaking” your computer system for broadband connections.

Full file at

D. Cable modem

Connects a personal computer to a cable-TV system that offers an internet connection. DSL, T1, and cable connections are always on.

Additional Information

For more information about always-on connections, go to:

E. Satellite wireless connections

Communications satellite transmits radio waves called microwaves from earth-based stations. To have a satellite internet connection, the user must have a service provider that supports 2-way transmission.

F. Wi-Fi & 3G

Other wireless transmission methods use radio waves. Wi-Fi, the IEEE 802.11 standards, is one type of wireless transmission; good for distances up to 300 feet from an access point (hotspot antenna). The hotspot can be connected to the internet via any method. Wireless 3G (third generation) does not need access points; it uses the existing cellphone system.

Panel 2.5 gives the data transmission rates for all the methods discussed.

G. Three kinds of internet access providers

ISPs = local, regional, or national provider of access to the internet (e.g., Earthlink and AT&T Worldnet); commercial online services = members-only service providers such as AOL and MSN; wireless internet service provider = internet connection for users of computers with wireless modems (AT&T Wireless, Verizon Wireless).

All internet access providers require user to use passwords to log on.

Additional Information

For some diagrams of different kinds of internet service provider setups, go to

2.2 How Does the Internet Work?

Key Question: What is the basic structure of the internet, and who controls it?

The internet consists of hundreds of thousands of smaller networks connected around the globe. This arrangement is based on the client/server network. A client computers requests data/services; the server, or host computer, supplies the data or services.

A. POPs, NAPs, backbones, and internet2

The first step in the internet connection begins with the user’s computer. Using the type of connection (dial-up, ISDN, DSL, cable, wireless) available, the user connects to the internet access provider.

1. The access provider provides a local point-of-presence (POP), a collection of modems and other equipment in a local area. The POP acts as a local gateway to the ISP’s network, when the user connects to the ISP.

2. The service provider connects to a network access point (NAP), a point on the internet where several connections come together. NAPs are owned by network service providers (such as MCI).

3.NAPs are connected by the internet backbone, a group of communications networks managed by several commercial companies that provide the major high-speed links across the country. The major backbone providers are MCI, Sprint, UUNET, AGIS and BBN.

B. Protocols, packets, & addresses

1. Protocol = set of conventions (standards or rules) that govern the format of data transmitted electronically. The protocol that enables all computers to use data transmitted on the internet is Transmission Control Protocol/Internet Protocol (TCP/IP). Protocols should be distinguished from technical standards, which tend to specify how to build a computer or related hardware device, or how the contents of a file are structured. Protocols are generally used in real-time communications, while standards are used to govern the structure of information committed to long-term storage.

Most protocols specify one or more of the following:

Detection of the underlying physical connection (wired or wireless), or the existence of the other endpoint or node

Handshaking (signals transmitted back and forth over a communications network that establish a valid connection between two stations)

Negotiation of various connection characteristics

How to start and end a message

How to format a message

What to do with corrupted or improperly formatted messages (error correction)

How to detect unexpected loss of the connection, and what to do next

Termination of the session or connection

Additional Information

Wikipedia has a lot of information on protocols:

2. Packets = fixed-length blocks of data for transmission. Packets do not need to follow the same routes to their destination. A packet is the fundamental unit of information carriage in all modern computer networks. A packet consists of a header, which contains the information needed to get the packet from the source to the destination, and a data area, which contains the information of the user who caused the creation of the packet. A good analogy is to consider a packet to be like a letter; the header is like the envelope, and the data area is whatever the person puts inside the envelope.

3. IP addresses = unique identification of every computer and device connected to the internet. Every client, server and network device must have a unique IP address for each network connection (network interface). Every IP packet contains a source IP address and a destination IP address. IP addresses are written in dotted decimal notation, which is four sets of numbers separated by periods; for example, 204.171.64.2. If you knew the IP address of a website, you could enter the dotted decimal number into your browser instead of the domain name. Dynamic IP addresses change each time a person connects to the internet; static IP addresses remain the same each time. Routers, firewalls and proxy servers use static addresses as do most servers and printers that serve multiple users. Client machines may use static or dynamic IP addresses. The IP address assigned to your service by your cable or DSL Internet provider is typically dynamic IP.

Additional Information

Want to find out what your IP address is while you’re online?

C. ICANN runs the internet

The Internet Corporation for Assigned Names and Numbers (ICANN) was established to regulate human-friendly internet domain names. Domain names include addresses, such as those ending with .com, .org, and .net, that overlie IP addresses. Everyone on the net adheres to standards established by ISOC (Internet Society).

Additional Information

At the 2005 World Summit on the Information Society held in Tunisia's capital, delegates from the 174 participating countries met with the aim of bridging the “digital divide” that separates rich and poor nations.

But even higher on the agenda was the demand to reduce U.S. control over the Internet. . . . In theory, no one is supposed to run or own the Internet, the most powerful network in the world and an entity upon which the global economy increasingly relies.

In reality though, it is in the hands of the American Internet Corporation for Assigned Names and Numbers (ICANN), based in California. . . .But the European Union and other countries are determined to water down its control, arguing that a truly international phenomenon should not be run by the United States and subject to a veto by the U.S. Department of Commerce. [CNN.com, 12/2/05]

Additional Information

The Internet Traffic Report monitors the flow of data around the world. It displays values between 0 and 100 for many networks. Higher values indicate faster and more reliable connections. Check out your area at .

2.3The World Wide Web

Key Question: How do the following work—websites, web pages, browsers, URLs, web portals, search tools, and search engines? What are HTML and hyperlinks?

A. Browsers, websites, & web pages

1. Browsers = software that enables people to find and access the various parts of the web, to surf the web.

2. Websites are locations on the web that have unique addresses, a set of interconnected web pages, usually including a homepage, generally located on the same server, and prepared and maintained as a collection of information by a person, group, or organization.

Additional Information

USAGE NOTE [from Answers.com]: The transition from World Wide Web site to Web site to website has progressed as rapidly as the technology itself. The development of website as a single lowercase word mirrors the development of other technological expressions which have tended to evolve into unhyphenated forms as they become more familiar. Thus email has recently been gaining ground over the forms E-mail and e-mail, especially in texts that are more technologically oriented. Similarly, there has been an increasing preference for closed forms like homepage, online, and printout.

3. Web pages = the documents on a website; it can include text, pictures, sound, and video. The home page, or welcome page, identifies the website and contains links to other pages on the site and other documents on the web.

B. How browsers find things

Browsers use URLs to find particular web pages.

1. URL (Uniform Resource Locator) = a string of characters that point to a specific piece of information on the web. A URL consists of the following:

a.)Web protocol (

b.)Name of the web server (domain name) (e.g., www.nps.gov)

c.)Directory on the server (parkname)

d.)File within that directory and extension (home.htm) [http://www.nps.gov/parkname/home.htm]

• http:// stands for HyperText Transfer Protocol
• domain name is the location on the internet, the particular web server (.gov, .com, .net, .edu, .org, .mil, .int); some domain names include country designations, such as .us (USA), .ca (Canada), .de (Germany)
• the directory name is the name of the file on the server from which the browser pulls the file
• the file name refers to the file sought by the user; the extension identifies the type of tile (extensions are not always used)

2. URLs and email addresses are not the same; email addresses use the @ symbol and identify mailbox locations on a server, not websites.

C. HTML & hyperlinks

1.Hypertext markup language (HTML) = set of special instructions that are used to specify document structure, formatting, and links to other multimedia documents. Extensible hypertext markup language (XHTML) is a successor to HTML. Web pages are built with HTML tags (codes) embedded in the text. HTML defines the page layout, fonts and graphic elements as well as the hypertext links to other documents on the web. Each link contains the URL, or address, of a web page residing on the same server or any server worldwide, hence “World Wide” Web.

A markup language can also be thought of as a “presentation language,” but it is not a programming language. You cannot “if this-do that” as you can in Java, JavaScript, or C++. However, in order to make pages interactive, programming code can be embedded in an HTML page. For example, JavaScript is widely interspersed in Web pages (HTML pages) for that purpose. (Programming languages are covered in Chapter 10.)

2. Hypertext links appear as underlined or color words/phrases; when clicked on, they link the user to other web pages. Links embedded within Web pages are addresses to other Web pages either stored on the same Web server or on a Web server anywhere in the world. This "hyperlink" concept is the foundation of the World Wide Web.

Icons and graphic elements of all sizes and shapes can also serve as clickable links but are more accurately called “hypergraphics.” Thus, hyperlinks are technically either hypertext or hypergraphics. In practice, the terms “hypertext” and “hyperlink” are mostly used, and often synonymously.