The Internet & the World Wide Web

Chapter 2

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 (www.optiontelecom.com/Tech_Support/data_trans_speeds.htm) that shows how quickly a 1-MB file can be transmitted via various bandwidths.

Transmission Connection Data link Throughput of 1 MB file Speed

2,400 bps Slow modem analog 55 minutes 33 seconds

9,600 bps Basic fax/modem analog 13 minutes 53 seconds

14.4 kbps Fast modem analog 9 minutes 16 seconds

28.8 kbps Faster modem analog 4 minutes 38 seconds

128 kbps Basic Rate - ISDN digital 1 minute 3 seconds

500 kbps Cable modem digital 16 seconds

1.544 Primary Rate - ISDN digital 1 minute 3 seconds

1.544 mbps T1 digital 5.2 seconds

Wireless (Telesat 12 mbps digital 0.67 seconds satellite)

45 mbps T3 digital 0.18 seconds

> 100 mbps ATM digital 0.08 seconds

155 mbps OC-3 digital < 0.08 seconds

622 mbps OC-12 digital < 0.02 seconds

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.

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:

www.gibson.vero-beach.fl.us/classes/internet/access.html

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.

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.

Get information about speeding up modem connections at www.inklineglobal.com/products/mb/ www.cbs-soft.com/speedconnect.htm http://www.sharewareconnection.com/modem-optimizer.htm

www.dslreports.com/tweaks discusses “tweaking” your computer system for broadband connections. 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.

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

http://www.techsoup.org/

http://www.harborresearch.com/harbor/

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

www.answers.com/internet%20access%20provider?gwp=11.

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

Wikipedia has a lot of information on protocols:

http://en.wikipedia.org/wiki/Communications_protocol

http://en.wikipedia.org/wiki/Protocol_%28computing%29

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.

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

www.formyip.com

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).

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]

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 www.internettrafficreport.com/main.htm.

2.3 The 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.

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 (http://)

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.

The hypertext concept was originally coined by Ted Nelson in the mid- 1960s as a method for making the computer respond to the way humans think and require information.

Web Exercise

The University of New York at Albany offers a guide to the internet: http://library.albany.edu/internet/

D. Using Your Browser to Get around the Web

1. The five basic elements of a browser are menu bar, toolbar, URL bar, workspace, status bar. Panel 2.11 illustrates these elements.

2. Starting out from home: the first page seen when starting up a browser is the home page or start page. A good start page offers links to sites frequently visited. Often the ISP will provide its own home page.

3. Personalizing your home page: users can often personalize their home page by following the directions provided with the first start page encountered.

4. Getting around — Back, Forward, Home, and Search features: the browser toolbar provides navigational aids. Back takes you back to the previous page. Forward lets you look again at a page you returned from, clicking on Home returns you to your home page, where you can start over again. Search displays a directory of search engine sites.

5. History lists allow you to quickly return to the pages you have recently visited.

6. Bookmarks or favorites let you store the URLs of web pages you frequently visit.

7. Interactivity — hyperlinks, radio buttons, and search (fill-in text) boxes: for any given web page, there are three possible ways to interact with it:

a.) Clicking on the hyperlinks

b.) Clicking on the radio button (panel 2.15)

c.) Typing text in the fill-in text box

8. Scrolling — clicking on the scroll arrows allows you to see the rest of the web page. Frame = web browser feature that enables a web page to be displayed in a separate scrollable window on screen. Older browsers do not support the frames feature, and many websites have a frames and nonframes version of the site to accommodate them. Additional Information

A frame is a data structure invented by Marvin Minsky in the 1970s. It refers to the physical layout of data. Data fields, memo fields, fixed length fields, variable length fields, records, word processing documents, spreadsheets, data files, database files and indexes are all examples of data structures.

10. Looking at two pages simultaneously — to look at more than one web page at the same time, you can position them side-by-side on your display screen by selecting File, New, Window.

E. Web Portals: starting points for finding information

Portals are gateway websites that offer a broad array of resources and services.

When logging on to a portal you can:

. check the portal’s home page for general information.

. use the subject guide to find a topic.

. use a search box and keywords to search for a topic

Popular portal sites are listed in Panel 2.18.

F. Search Engines

Search services are organizations that maintain databases accessible through websites to help users find information on the internet. Search services maintain search engines, programs that enable users top ask questions or use keywords to locate information. Search services also use spiders (crawlers, bots, agents), special programs that “crawl” through the web to index topics for the database.

A single search engine does not cover the entire web, and search engines differ in what they cover.

The first Web search engine was Wandex, a now-defunct index collected by the World Wide Web Wanderer, a web crawler developed by Matthew Gray at MIT in 1993. Another very early search engine, Aliweb, also appeared in 1993. One of the first engines to later become a major commercial endeavor was Lycos, which started at Carnegie Mellon University as a research project in 1994.

Soon after, many search engines appeared and vied for popularity. These included WebCrawler, Hotbot, Excite, Infoseek, Inktomi, Open Text, Northern Light, and AltaVista.

In 2002, Yahoo! acquired Inktomi and in 2003, Yahoo! acquired Overture, which owned AlltheWeb and Altavista. In 2004, Yahoo! launched its own search engine based on the combined technologies of its acquisitions and providing a service that gave pre-eminence to the Web search engine over the directory.

Before the advent of the Web, there were search engines for other protocols or uses, such as the Archie search engine for anonymous FTP sites and the Veronica search engine for the Gopher protocol.

Osmar R. Zaïane’s From Resource Discovery to Knowledge Discovery on the Internet http://citeseer.ist.psu.edu/117999.html details the history of search engine technology prior to the emergence of Google.

Recent additions to the list of search engines include a9.com, AlltheWeb, Ask Jeeves, Clusty, Gigablast, Ez2Find, GoHook, Kartoo, Laplounge, Mamma, Plazoo, Snap, Teoma, Walhello and WiseNut, and Copernic.

Around 2001, the Google search engine rose to prominence. Its success was based in part on the concept of link popularity and PageRank. How many other web sites and web pages link to a given page is taken into consideration with PageRank, on the premise that good or desirable pages are linked to more than others.

See “How Search Engines Work” at

www.answers.com/search%20engine?gwp=11

F. Four web search tools

1. Keyword indexes: allows users to search for information by typing one or more keywords; the search engine then displays a list of web pages (hits) that contain the keywords. (Google, Gigablast, HotBot, MSN Search)

2. Subject directories: allows the user to search by selecting lists of categories or topics. (Netscape, MSN Directory, Yahoo!)

3. Metasearch sites: allow users to search using several search engines simultaneously. (Dogpile, MetaCrawler, ProFusion).

4. Specialized search engines: users can also use search engines geared to individual topics, such as movies, jobs, health.

What do these terms mean: glurge gallery, inboxer rebellion, wooden spoons, rumors of war? Go to

www.snopes.com

and find out. Then check out a category of interest to you and see how much untrue information is circulating about it.

Get information on Copernic, rated by some IT writers as the best overall search engine, at

www.copernic.com .

Web Exercise The following website gives a list of search engines, categorized on various bases. You can review the ratings for popular search engines on different basis here. http://searchenginewatch.com/

G. Tips for Smart Searching

1. Just browsing: try typing keywords into a subject directory or a metasearch engine.

2. Looking for specific information: try Answers.com “one-click search” or type keywords into both a major keyword index such as Google and a specialized search engine.

3. Looking for everything possible on one subject: Use all the engine types.

Teaching Tip

Remind students that the same rules apply for validating, sourcing, and crediting internet research applies to hardcopy research in libraries. Panel 2.24 and the Practical Action box on p. 78 give some guidelines for online research and mention some websites where students can find additional information. The Chicago Manual of Style, 15 ed., also provides information on this topic.

The following website gives a detailed insight into how search engines work

http://webreference.com/content/search/

It also guides you how to choose a search engine for the best search results in a given scenario at the following link.

http://webreference.com/content/search/features.html#which_search_page H. Multimedia search tools

1. Still images and videos: some search indexes deal with images; e.g., Columbia University’s Webseek and Bridges of the World.

2. Audio and video: other search engines deal with audio as well as video; e.g., CampaignSearch.com, StreamSage, and ShadowTV.

3. Multiple sources, including music: search engines such as A9 search multiple sources as well as music sources.

4. Scholarly: search engines such as Google Scholar search scholarly abstracts, books, white papers, and so on.

Additional Information The Practical Action box on p. 80 provides some techniques for web searches. More web search tips and tutorials are at

http://searchenginewatch.com/

I. Desktop searches (searching the hard disk)

Users sometimes have so much stuff and/or unorganized stuff on their hard disks that they lose track of it. Desktop search engines help them find things. Free desktop search tools can be downloaded from the internet. Google’s is one of the most popular.

Tagging is used to categorize what users find on the web. Tags are not the same as bookmarks / favorites because they can be shared with other people. Tagging programs can be downloaded from sites such as BlinkList, del.icio.us, and FlickR.

2.4 Email & Other Ways of Communicating over the Web

Key Question: What are email and webmail, attachments, instant messaging, FTP, newsgroups, listservs, real-time chat, and netiquette?

Email is the principal use of the internet. A. Two ways to send and receive email

1. Get an email (client) program as part of other computer software; this program interacts with an ISP’s email server. Users can use the ISP’s own email program (e.g., Earthlink’s program) or a program that comes with a computer or a browser (e.g., MS Outlook Express, Netscape Mail), or they can buy their own proprietary program (such as Eudora).

2. Use web-based email via a website run by portals such as Yahoo!.

B. How to use email

Email addresses have the following components:

1. user name (user ID): identifies who is at the address [Joe_Black]

2. domain name: located after the @ symbol, tells the location of the address [@earthlink]

3. top-level domain (domain code): three-letter extension indicates the type of domain (e.g., commercial, educational, military) [.net]

4. country: some email addresses also in include a country designation (e.g., .us, .ca, .de, .mx) [.us]

[[email protected]]

Web Exercise

Ask students to browse the following website for a detailed tutorial on how e-mail works:

www.learnthenet.com/english/section/email.html

5. Type email addresses carefully

Remind students that addresses can have no typos and that some are case- sensitive. 6. Use the Reply command carefully

Remind students of the stories mentioned in the IM, Chapter 1, about people who accidentally used Rely All instead of just Reply.

7. Use the address-book feature

Remind students to use their email programs address book feature so that they don’t have to repeatedly type in email addresses every time they want to send emails to people/groups whom they write to frequently.

8. Deal with each email only once

Don’t use the inbox to store emails; delete them or put them in folders organized according to sender or topic.

9. Don’t “bloat” emails

Don’t put lots of typestyles, logos, icons, colors, etc. into emails; they will take too long to send and for others to download (receive).

C. Sorting email

Email programs usually offer filters to automatically organize email according to users’ instructions.

D. Attachments

Almost anything, including sound and video clips as well as text and graphic items, that a user saves on his/her computer can be attached to an email. However, the email recipient must have the same software used to create the attachment in order to be able to open the attachment. Large attached items may not clear the ISP’s server or be accepted by the recipient’s computer, so students should be cautioned to keep their attachments small or to compress them before attaching them. (Compression is covered in Chapter 8.)

Also, viruses can be spread through attachments. For now, tell students not to open attachments from unknown sources, or indeed to open any at all, until they know how to install antivirus programs to check for viruses. (Viruses are covered in Chapter 6.) Additional Information

Remind students that email is company property. The company can review an employee’s email without permission; indeed, many companies use surveillance software to monitor employees’ online activities. Employees should only send email that is acceptable to the work environment.

E. Instant Messaging (IM)

Users on a given email system can send a message and have it pop up instantly (in real-time) on the screen of anyone else logged onto that system. Messages appear in a window, a dedicated rectangular area, so that users can exchange messages almost instantaneously while operating other programs.

1. To use instant messaging, users must register with an IM service such as AOL Instant Messenger, MSN Messenger, and Yahoo! Messenger and then download the supplier’s IM software. IM is available on computers and smart cellphones.

2. Drawbacks of IM :

a.) Lack of privacy

b.) Lack of common standards

c.) Time wasters when you have to get work done

IM requires that both parties be logged onto their IM service at the same time. Also known as a "chatting," IM has become very popular for both business and personal use. In business, IM provides a way to contact coworkers any time of the day, providing they are at their computers or using a compatible cellphone.

Email and instant messaging are often used in a similar manner, but email is not real-time, and there can be delays of several minutes or more. Like email attachments, IM systems generally allow for file transfers. Also like -mail, some systems let you send messages even if the recipient is not currently online. IM is expected to promote IP telephony by allowing users the option of switching from typing to speaking (from text chat to voice chat).

To set up instant messaging, you have to add the usernames of the people you want to message with to your "buddy list" (friend list, contact list). When they log on to the internet with their IM software, and provided they have not configured themselves as "invisible,” you are instantly alerted. When they log off, you are also notified. Each system has its own method for blocking incoming and outgoing messages.

Instant messaging became popular after Israeli-based ICQ introduced its service in 1996, which was later acquired by AOL. Today, AOL's Instant Messenger (AIM), AOL's ICQ, Microsoft's MSN Messenger/Windows Messenger, and Yahoo! Messenger are the major services. Cerulean Studio's Trillian (www.ceruleanstudios.com) is a single IM program that works with all these services as well as the Internet's traditional IRC chat rooms. Additional Information

For a list of IM services and products, go to

www.instantmessagingplanet.com

Group Exercise

Have a person online during the class period, preferably someone from another country, and demonstrate instant messaging by sending messages to the person. If there are several computers in the classroom, have the students instant message each other.

F. FTP

File Transfer Protocol is a software standard that allows file transfer between computers, including those with different operating systems. Anonymous FTP sites are open to everyone; other FTP sites require registration and passwords. FTP transfer uses FTP client programs that come with most operating systems, such as Windows, Linux, and Unix, or that are proprietary, such as Cute and Fetch.

Email was originally design to transfer only ASCII test, and it still cannot be used to transfer certain types of binary files. Attachments can be used to transfer other types of tiles, but FTP can be used for large files. For a list of FTP clients, go to

www.answers.com/main/ntquery? method=4&dsid=2222&dekey=List+of+FTP+clients&gwp=8&curtab=2222_1&link text=List%20of%20FTP%20clients

G. Newsgroups

Newsgroups are written online discussion, dedicated to a particular topic, that are posted on a “bulletin board” (message board). There are thousands of news groups; some are free, and some charge participation fees. Newsgroups are on a worldwide public network of servers called Usenet. To participate, users need a newsreader, a program included with most browsers.

www.answers.com/newsgroups?gwp=11

for detailed information on newsgroups.

E. Listserv

Automatic mailing-list server that sends email to subscribers who regularly participate in discussion topics.

The word "Listserv" has come to be used loosely as a generic term for any mailing list application. However, it is a registered trademark licensed to L-Soft International, Inc., who market the application commercially. For this reason, it is not legal to use the term commercially, except in reference to this product.

www.lsoft.com/products/listserv.asp

If you are receiving email from companies that ask you to “click here” to unsubscribe, they are using Listserv technology.

F. Real-time chat

Typed online discussions occurring in real time, rather like a telephone conversation, except typed and displayed on a screen. Internet Relay Service (IRC) supports chatting and is available through browsers.

There are hundreds of IRC channels on numerous subjects that are hosted on IRC servers around the world. After joining a channel, your messages are broadcast to everyone listening to that channel. IRC client programs provide a graphical interface for all functions, including logging onto popular servers and obtaining a list of their active channels.

IRC was created by Jarkko Oikarinen in late August 1988 to replace a program called MUT (MultiUser Talk) on a BBS (bulletin board system) called OuluBox in Finland.

IRC gained prominence when it was used behind the Iron Curtain to report on the fall of the USSR during a media blackout. It was later used in a similar fashion by Kuwaitis during the Iraqi invasion.

G. Netiquette

Netiquette = “network etiquette”; appropriate online behavior = don’t waste people’s time, and don’t write/say anything that you wouldn’t say in person.

Some rules of netiquette:

. Consult FAQs - most online groups post FAQs (Frequently Asked Questions) that explain expected norms of online behavior for a particular group. . Avoid Flaming - writing an online message that uses derogatory, obscene, or inappropriate language.

. Can use emoticons, keyboard-produced pictorial representations of expressions, to smooth communications.

. Don’t SHOUT - use of all-capital letters is considered the equivalent of SHOUTING.

. Be careful with jokes - jokes in an email may be taken as insults or criticism.

. Avoid Sloppiness - avoid spelling and grammatical errors. Try to avoid criticizing others’ sloppiness.

. Don’t send large file attachments, unless requested - this may tie up a system with a slow dial-up connection.

. When replying, quote only the relevant portion - don’t send back the entire message. Edit the original text down to the relevant paragraph and then put in your response immediately following.

. Avoid overforwarding - do not automatically forward emails without verifying their contents.

2.5 The Online Gold Mine: More Internet Resources

Key Question: What are internet telephony, various kinds of multimedia, and RSS and different web feeds—webcasting, blogging, podcasting—and types of e-commerce?

A. Telephony

Internet telephony (Voice over Internet Protocol, or VoIP) allows inexpensive phone calls.

Internet telephony servers link telephone lines to the internet.

www.answers.com/topic/telephony-server?hl=internet&hl=telephony

Students can experiment with internet telephony for free, and watch an animated explanation, at: www.skype.com/

B. Multimedia on the web

1. Plug-ins: Early browsers were unable to handle many graphics, sound, and video (multimedia) files, so external applications called plug-ins were developed for users to download to their systems. Plug-ins are computer program that interact with another program to provide a specific function, to allow users to play or view certain files.

Plug-ins are slightly different from extensions, which modify or add to existing functionality. For more on plug-ins, go to

www.answers.com/topic/plugin?method=6

For a list of free plug-ins of many types, go to

http://desktop.google.com/plugins

2. Multimedia development: developers of multimedia items on web pages use applets, links to small programs that quickly download to users’ computers and that can be run by most browsers. The applets are written in Java, a programming language developed for this purpose. (Java is discussed in Chapter 10.) Java supports animation, music, graphics, and interactivity. Microsoft’s answer to Java is Studio.net.

3. Text and images: all kinds of text documents are available on the web, as are millions of images, including maps, aerial views of one’s house, and photo archives.

4. Animation, the rapid sequencing of still images to create the illusion of motion, is used in video games as well a many websites. Additional Information

The two most popular animation formats on the Web are animated GIFs and Flash:

www.answers.com/main/ntquery? method=4&dsid=1512&dekey=animated+GIF&gwp=11&curtab=1512_1&linktext =animated%20GIF

www.answers.com/main/ntquery? method=4&dsid=1512&dekey=Flash&gwp=11&curtab=1512_1&linktext=Flash

5. Video: Video files can be downloaded and then viewed or be viewed as they are being downloaded (streaming video).

QuickTime (Mac) and RealPlayer (PC) are two popular video plug-ins (they also download other types of files).

6. Audio: Audio files also can be downloaded in entirety and then played or be listened to as they are being downloaded. Napster and iTunes are examples of the first type; RealAudio is the second type.

C. Webcasting, blogging, & podcasting

1. Instead of having to go out on the internet and search for information (pull technology), users can arrange for information to come to them, which is called push technology. Webcasting is one kind of push technology: customized text, video, and audio are sent to the user’s computer on a scheduled basis.

RSS newsreaders also use push technology. RSS uses XML (extensible markup language) to allow computers to exchange information. XML is also the basis for the blogosphere, the “cyber area” where bloggers (web loggers) maintain their diary-style web pages.

Additional Information The XML-based format for publishing headlines of the latest updates posted to a blog or website for use by other websites and direct retrieval by end users is called a syndication format. The format, known as a “feed,” “news feed,” or “web feed,” includes a headline, short description, and link to the article. For a master list of syndication feeds, visit www.syndic8.com

A syndication format enables Web sites that share a common interest to expand their content by publishing news headlines from other websites and blogs. In fact, a large news site can be entirely made up of syndication feeds.

By subscribing to several feeds, it enables users to quickly review the latest news on those sites from a consolidated index rather than browsing from site to site. The software viewer, which is called an “RSS reader,” “newsreader,” “news aggregator,” “feed viewer,” or “headline viewer,” automatically searches selected sites and presents the latest headlines in chronological order to the user. Viewer plug-ins for Web browsers are available.

In addition, there are we sites that search for and aggregate feeds that are displayed entirely in the browser. Subscribing to a site such as BlogLines (www.bloglines.com) can eliminate the need to download a news reader or a plug-in, as any web browser can be used. A source for finding feeds is (http://www.google.com/help/reader/feeds.html), a search engine devoted to finding sites with syndication feeds.

Web Exercise

Ask students to use a search engine, type the word blog or the words web log and the name of a topic that interests them—for example, blog AND Clydesdales. What are people saying about this topic? Do students think that bloggers’ views are useful? Do students think that bloggers’ opinions should be accorded any particular importance? Ask students to research online short reports on the reliability and significance of blogs. Ask them to give pros and cons.

Podcasting is the recording of internet radio or similar internet audio programs. The term is used for recording anything and everything to be played back on a digital player.

D. E-commerce

E-commerce (electronic commerce) refers to conducting business activities online. One type of e-commerce is B2C (business-to-consumer), where by businesses sell goods and/or services to consumers.

Another type of e-commerce is B2B (business-to-business) commerce, whereby companies exchange goods and services directly, without traditional intermediaries.

Online finance can be a B2C or a B2B situation. It can include bill paying, stock trading, investing, tax paying, bank account managing, loan processing, and so on.

Online auctions can be a C2C (consumer-to-consumer) arrangement: person-to-person auctions, such as those run by eBay, or B2C vendor auctions, such as those run by OnSale.

Online job hunting is also part of e-commerce. (Job hunting was discussed in Chapter 1.)

Introduction to E-commerce tutorial:

www.online-commerce.com/tutorial.html

E. Relationships

People also use the internet to track down old friends, join high school and college alumni sites, do background checks on people, meet new people, and join online dating services. 2.6 The Intrusive Internet: Snooping, Spamming, Spoofing, Phishing, Pharming, Cookies, & Spyware

Key Question: How can I protect myself against snoopers, spam, spoofing, phishing, pharming, cookies, and spyware—adware, browser and search hijackers, and key loggers?

A. Snooping

Snooping means reading other people’s email. Users should realize that any email can be read by anyone, and they should restrict their content and vocabulary accordingly. Even deleted (trashed) email can be read; software programs can be installed to completely eliminate deleted files on the user’s computer, but the emails may be stored in places other then the user’s computer.

B. Spam

Spam is unsolicited email, which is becoming an overwhelming, time-consuming problem for many email users.

The textbook mentions (p. 99) one explanation for the origin of “spam” as applied to unwanted email. Another version is that the term was supposedly coined from a Monty Python’s Flying Circus comedy sketch in the early 1970s, in which every item on a restaurant menu contained Spam, and there was nothing a customer could do to get a meal without it. The sketch derived from the fact that in England during World War II, Spam (Hormel's processed meat) was abundantly available while other foods were rationed.

The sketch begins as follows: Mr. Bun: Morning. Waitress: Morning. Mr. Bun: Well, what you got? Waitress: Well, there's egg and bacon; egg, sausage, and bacon; egg and spam; egg, bacon and spam; egg, bacon, sausage, and spam; spam, bacon, sausage, and spam; spam, egg, spam, spam, bacon, and spam; spam, sausage, spam, spam, spam, bacon, spam, tomato, and spam; spam, spam, spam, egg, and spam; (Vikings start singing in background) spam, spam, spam, spam, spam, spam, baked beans, spam, spam, spam and spam . . .

Many believe spam is an acronym for "sales promotional advertising mail" or "simultaneously posted advertising message."

Visit the following site to understand more about spam and what to do about it:

www.pcworld.com/news/article/0,aid,113431,00.asp

Some ways to deal with spam are given in the Practical Action box on p. 100; the following website gives reviews of spam-blocking software:

http://spam-software.6starreviews.com/?refer=CTgoog&keyword=spam%20 blocking %20software&gclid=CJbXnN2B54ECFTEkCwodsmsZvA

This site covers antispam laws in the USA and in Europe:

www.spamlaws.com

C. Spoofing, Phishing, & Pharming

1. Spoofing: forgery of an email sender’s name so that the message appears to have come from someone other than the real sender.

For a detailed discussion of email authentication, go to

www.answers.com/main/ntquery?method=4&dsid=1512&dekey=e- mail+authentication&gwp=8&curtab=1512_1&linktext=e-mail%20authentication

2. Phishing: sending of a forged email that directs receivers to a replica (fake) of a real web page with the intention of convincing people to share personal, financial, and/or password data. The fake website looks like the real thing and is usually for a “bank,” a “Store,” or an online company.

For an example of a phishing attempt, go to

http://home.pcisys.net/~tbc/misc/phish001.htm

3. Pharming: by implanting malicious software on a user’s computer, redirecting the user’s computer to a fake website even though the user has typed in a correct address into his or her browser. After the user is at the fake website, he /she will be prompted to enter personal information.

Pharming can also be done by hacking into DNS servers and changing IP addresses. Users are automatically redirected to the bogus site, at least for some period of time until the DNS records can be restored.

For example, if a bank's DNS were changed, users could be redirected to a website that looks familiar. The bogus site could just collect usernames and passwords, or it could, using some pretense, request financial information. Unlike phishing schemes that use email to make people go to the phony site, pharming is more natural. Users are going to the site on their own and are certainly not suspicious because the pages look familiar.

D. Cookies

Cookies are little text files left on a computer user’s hard disk by some websites. The websites retrieve the data when the user visits again. Cookies provide a way for the website to identify users and keep track of their preferences.

The default settings in your web browser typically allow "first-party" cookies that do not contain any personal information but not "third-party" cookies. First-party cookies are ones that are created by the website you are visiting. Third-party cookies are created by a website other than the one you are currently visiting; for example, by a third-party advertiser on that site. The purpose of such cookies is usually to track your surfing habits, which is why third-party cookies are considered an invasion of privacy and riskier than first-party cookies.

Users can prevent all cookies from being stored in their computers, but that severely limits the web surfing experience. To change settings, look for the browser’s cookie options in the Options or Preferences menu.

Proprietary software programs such as Norton Internet Security and Webroot also allow users to individualize cookie settings.

What happens if you refuse cookies? Read the articles at

http://computer.howstuffworks.com/cookie.htm

http://hea-www.harvard.edu/~fine/opinions/cookies.html

www.perlservices.net/en/faq/cookies.shtml

E. Spyware

Pop-up ads are a form of spyware; when users visit certain websites, these sites “pop” ads up on users’ computer screens. Spyware is a form of software that is surreptitiously installed on a computer via the web; once installed it allows the installer to gather personal information.

1. Adware is a kind of spyware that tracks web surfing or online buying so that marketers can send the users targeted and unsolicited op-up ads and other ads.

2. Browser hijackers change settings in the user’s browser without the user’s knowledge, often replacing the home page with another web page. Search hijackers intercept users’ legitimate search requests made to real search engines and return results from phony search services designed to send the users to sites run by the hijackers. 3. Key loggers record each character typed by a user and transmit that information to someone else on the internet, making it possible for strangers to learn the user’s passwords and other information.

The Practical Action Box on p. 103 gives a few tips for avoiding spyware. Proprietary software, such as

Spyware can come bundled with an otherwise apparently useful program. The makers of such packages usually make them available for download free of charge, so as to encourage wide uptake of the spyware component. This applies especially with file-sharing clients such as Kazaa and earlier versions of Bearshare. [Advise students to be careful of free download; if they like to do a lot of free downloading, they should consider purchasing a program such as.]

Spyware can also take advantage of security flaws in Microsoft Internet Explorer. Answers to End-of-Chapter Text Exercises

Self-Test Questions

1. bits per second (bps), kilobits per second (Kbps), megabits per second (Mbps), gigabits per second (Gbps) 2. cable modem 3. satellite (communications satellite) 4. ISP (internet service provider) 5. window 6. flaming 7. browser (web browser) 8. website 9. protocol 10. plug-in 11. spam 12. bandwidth 13. URL 14. cookies 15. phishing 16. key logger

Multiple-Choice Questions

1. b 2. c 3. d 4. c 5. d 6. b 7. c 8. e 9. b 10. a 11. b 12. b

True/False Question

1. F 2. F 3. F 4. F 5. F 6. F 7. T 8. F 9. T 10. F

Short-Answer Questions

1. DSL, ISDN, cable modem, satellite, T1, radio waves

2. To log on means to make a connection to a remote computer. Users must be familiar with log- on procedures to go online.

3. Netiquette short for “network etiquette,” provides guides to appropriate online behavior. In general, netiquette has two basic rules: (a) Don’t waste people’s time, and (b) don’t say anything to a person online that you wouldn’t say to his or her face.

4. Bandwidth refers to how much data—text, voice, video, and so on—can be sent through a communications channel in a given amount of time. Different communications systems use different bandwidths for different purposes. The wider the bandwidth, the faster data can be transmitted.

5. Whereas with e-mail you can connect only with specific addresses you know about, with the Web you have hypertext, a system in which documents scattered across many internet sites are directly linked, so that a word or phrase in one document becomes a connection to a document in a different place. Links are indicated by underlining or highlighting. If the user clicks on the link, he or she is taken to another document or website.

6. A cable modem connects a computer to the internet via a cable-TV system. DSL (digital subscriber line) uses special hardware and software to transmit data over regular phone lines. DSL is faster than standard data transmission over regular phone lines, and cable modem transmission is faster than DSL.

7. The internet is a worldwide computer network that connects hundreds of thousands of smaller networks. No one owns the internet; its components are owned and shared by thousands of private and public entities. When you use your personal computer at home, you connect to the internet via your local loop, over telephone wires or cable. The local loop connects you to your internet service provider (ISP), whose headquarters can be almost anywhere but who provides local points-of-presence (POPs) around the country, so users don’t have to pay long-distance charges to connect. The POP acts as a local gateway to the ISP’s network. The ISP functions as an interface between you and the rest of the internet. Some ISPs have their own high-speed backbones to transmit data; others lease backbone connections (network access points, or NAPs) through network service providers (NSPs) run by major communications companies. Each time you connect to the internet, your ISP assigns you a temporary internet protocol (IP) address, so that your location can be identified (to enable data transmission to your computer). The protocol, or set of standards, or rules, that enables all computers to use data transmitted on the internet is TCP/IP (Transmission Control Protocol/Internet Protocol).

Although no one owns the internet, everyone on the net adheres to standards overseen by ISOC (Internet Society). ICANN (Internet Corporation for Assigned Names and Numbers) regulates internet domain names.

8. IMAP (Internet Message Access Protocol) offers expanded functions compared to POP3 (Post Office Protocol version 3) for retrieving email; for example, with IMAP one can search through email messages while they are still on the ISP’s server—before one downloads them.

9. (See #7.)

10. (See #7.) 11. A dynamic IP address (internet protocol address) changes each time the user connects his/her computer to the internet; a static IP address remains the same. Established organizational websites (such as ISPs) have static IP addresses.

12. A blog (weblog) is an internet journal, a kind of online diary, maintained by a blogger.

13. (See #7.)

14. B2B is business-to-business e-commerce; the electronic sale or exchange of goods or services directly between companies.

15. Adware, browser hijacker, search hijacker, key logger

Responses to Knowledge in Action and Web exercises will vary throughout.