Lecture 4 - Internet Lecture

THE INTERNET

What is the InternetThe internet is a publicly available, global network of computersIt interconnects billions of Users. For example:BusinessesCitizensGovernmentsAcademic InstitutionsResearch CentersLibrariesEtc.

Provides a Common Communications System for Diverse Computing and Network Environments

Still Rapidly Expanding

Involves Numerous Technologies (Not a Single Technology)

*Internet History MilestonesARPANETINTERNET1969 ARPANETR&D Project1991World Wide Web Released by Tim-Berners Lee1974Vinton Cerf and Robert Kahn Initiated TCP/IP1983DOD Mandated Adoption of TCP/IP1983ARPANET Split into ARPANET and MILNET1985NSFNET founded by The National Science Foundation 1993Web Browser Mosaic invented by Mark Andreesen

August 1962: First proposal for building a computer network

Made by J. C. R. Licklider of MIT

ARPANETBuilt by the Advanced Research Projects Agency (ARPA) in the 1960sGrew quickly during the early 1970s

NSFNet: A national network built by the National Science Foundation (NSF)

October 24, 1995: Formal acceptance of the term Internet

Internet service providers start offering Internet access once provided by the ARPANET and NSFNet

History of the InternetWho controls the Internet?No oneccit is a public, cooperative, and independent networkSeveral organizations set standards

Terms to Be Familiar With:

Browser--Contains the basic software you need in order to find, retrieve, view, and send information over the Internet.Download--To copy data from a remote computer to a local computer. Upload To send data from a local computer to a remote computer.E-mail - E-mail (electronic mail) is the exchange of computer-stored messages by telecommunication. E-mail can be distributed to lists of people as well as to individuals.

Filter - Software that allows targeted sites to be blocked from view. Example: X-Stop, AOL@SchoolHome Page - The beginning "page" of any site. HTML (HyperText Markup Language) - The coding language used to create documents for use on the World Wide Web. There are three-letter suffixes used in coding that help to identify the type location one is viewingHTTP (HyperText Transport Protocol) - the set of rules for exchanging files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web. Relative to the TCP/IP suite of protocols (which are the basis for information exchange on the Internet), HTTP is an application protocol. Hypertext - Generally any text that contains "links" to other text.

Search Engine - A web server that collects data from other web servers and puts it into a database (much like an index), it provides links to pages that contain the object of your search.

TCP/IP -- TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language or protocol of the Internet. It can also be used as a communications protocol in a private network (either an intranet or an extranet). When you are set up with direct access to the Internet, your computer is provided with a copy of the TCP/IP program just as every other computer that you may send messages to or get information from also has a copy of TCP/IP.

URL (Uniform Resource Locator) - The Internet address. The prefix of a URL indicates which area of the Internet will be accessed. URLs look differently depending on the Internet resource you are seeking.

WWW (World Wide Web) - A technical definition of the World Wide Web is: all the resources and users on the Internet that are using the Hypertext Transfer Protocol (HTTP).

The InternetWhat are some services found on the Internet?

How Internet WorksHow we connect to Internet and how data travels on the Net?

High-speed connection

Slow-speed technology

How the Internet WorksHow can you connect to the Internet?Dial-up access modem in your computer uses a standard telephone line to connect to the Internet

Digital subscriber line (DSL), cable telephone Internet services (CATV), cable modem provide connections using regular copper linesConnection is always on whenever the computer is runningConnection must be established each time you log on. Slow but inexpensive

How the Internet WorksWhat are ways to access the Internet?ISP, Regional or NationalWireless Internet Service Provider

InternetHow it works? (Technically)Your computerModemDial up ProgramTelephone lines/ CablesISPServer (one of the main 9)it mean you are on InternetYour final destination Either a website or chatting with friend

IP AddressesInternet Relies on addressing system much like the traditional post service for sending and receiving informationIP (Internet Protocol) Address are numbers assigned to identify each computer connected to the InternetThe are four groups of numbers separated by a period (full stop) likeIMS Network has address (172.16.21.55)It is difficult to remember each number series so usually text versions of these number series are used known as Domain NameFamous domain names are com, edu, gov

How the Internet WorksWhat is a domain name?Text version of Internet protocol (IP) addressNumber that uniquely identifies each computer or device connected to Internet

World Wide WebThe Gateway to Information

The World Wide WebWhat is the World Wide Web (WWW)?

The World Wide WebWhat is a Web browser?Program that allows you to view Web pages

The World Wide WebWhat is a home page?The first page that a Web site presents Often provides connections to other Web pages

The World Wide WebWhat is downloading?The process of a computer receiving informationDepending upon connection speed, downloading can take from a few seconds to several minutes

The World Wide WebWhat is a URL?Unique address for a Web pageA web server delivers the Web page to your computer

This address is for anInternet server that usesThe hypertext transfer protocol.This site belongs to acompany named Glencoe.This site is on the partof the Internet knownas the World Wide Web.To find the specific Web pagesthat accompany this book, yourbrowser follows the URLs pathto a folder named norton, thento a subfolder named online.

Web AddressesEvery Web Site has a unique address called a URL (Uniform Resource Locator) For Example Web Site of Ford Motors has a Web Address (www.ford.com)You need to enter the web addresses correctly in your web browser otherwise it wont open the desired page for you The entered web addresses will deliver the requested web pages from the computer called Web Servers

The World Wide WebWhat is a hyperlink (link)?Item found elsewhere on same Web pageDifferent Web page at same Web siteWeb page at a different Web siteBuilt-in connection to another related Web page location

The World Wide WebHow can you recognize links?A link can be text or an image

Pointer changes to a small hand when you point to a linkText links are usually underlined and in a different color

The World Wide WebWhat is a search engine?Program used to find Web sites and Web pages by entering words or phrases called search textAlso called a keyword

The World Wide WebWhat is a hit?Any Web site name that is listed as the result of a search

The World Wide WebWhat is a subject directory?Search tool with organized set of topics and subtopicsLets you find information by clicking links rather than entering keywords

The World Wide WebWhat are the eight basic types of Web sites?

The World Wide WebWhat is a personal Web site?Web page maintained by private individualReasons: sharing life experience with the world or job hunting

The World Wide WebWhat is multimedia?Application integrating text with other media elementsGraphicsAnimationAudioVideoVirtual reality

The World Wide WebWhat is a thumbnail?Small version of a larger graphic imagecused to improve Web page display timeUsually click on thumbnail to display larger image

The World Wide WebWhat is animation?Appearance of motion created by displaying a series of still images in sequence

The World Wide WebWhat is audio?Music, speech, or any other soundIndividual compressed sound files that you download from the Web to your computerCommon Web audio file formats are MP3, WAV, WMA (Windows Media Audio), MPEG, RealAudio, and QuickTimeOnce downloaded, you can play (listen to) the contents of the files

The World Wide WebWhat is streaming audio?Transfers data in a continuous and even flowEnables you to listen to the sound as it downloads to your computerRadio stations use streaming audio to broadcast over the Web

The World Wide WebWhat is video?Consists of full-motion images with sound played back at various speedsMPEG (Moving Pictures Experts Group) is popular video compression standard

The World Wide WebWhat are plug-ins?Programs that extend the capability of a browserYou can download many plug-ins at no cost from various Web sites

Business to business (B2B) Business providing goods and services to other businessesConsumer to consumer (C2C) One consumer sells directly to anotherElectronic CommerceWhat is e-commerce?Business to consumer (B2C) Sale of goods to general publicShort for electronic commerceBusiness transaction that occurs over the Internet

E-Commerce (Examples)Amazon (B2C)

Other Internet ServicesWhat is e-mail?Short for electronic mailThe transmission of messages and files via a computer networkMessages can consist of simple text or can contain attachments, such as documents, graphics, or audio/video clipsInternet access providers usually provide an e-mail programSome Web sitessuch as MSN Hotmail and Yahoo!provide free e-mail servicesOne of the original services on the Internet

Things You Can Do with Email

Compose and Send: write an email and send it to others.Reply: reply to an email that you received.Forward: pass on an email that you received to others.Attachment: You can send files with your email such as:pictures, music, software and documents

Other Internet ServicesWhat is an e-mail address?Unique name that consists of a user name and domain name that identifies the user

Two Ways to Get Email

1. Provided by your Internet Service ProviderMonthly fee for internet connection often includes email service.Aliant - [email protected] - @eastlink.ca

2. Free Web-Based Service ProvidersAdvertising on the site pays for the service.Gmail - @gmail.comHotmail - @hotmail.com

Other Internet ServicesWhat is FTP?FTP (File Transfer Protocol) is the simplest and most secure way to exchange files over the Internet. Whether you know it or not, you most likely use FTP all the time. File Transfer ProtocolInternet standard that allows you to upload and download files with other computers on the Internet

Other Internet ServicesWhat are newsgroups and message boards?NewsgroupMany Web sites use message boards because they are easier to useOnline area where users discuss a particular subjectMessage boardType of discussion group

Other Internet ServicesWhat is a mailing list?Group of e-mail addresses given a single nameWhen a message is sent to the mailing list, everyone on the list receives the messageTo add your name to a mailing list you must subscribe to it; to remove your name you must unsubscribe

Other Internet ServicesWhat is a chat?Real-time typed conversation that takes place on a computerChat room is location on server that permits users to discuss topics of interest

Other Internet ServicesWhat is instant messaging (IM)?A real-time Internet communications service that notifies you when one or more people are online and allows you to exchange messages or files

NetiquetteWhat is netiquette?Golden Rule: Treat others as you would like them to treat you.Code of acceptable behaviors users should follow while on the Internet

Web PublishingWhat is Web publishing?Development and maintenance of Web pages

Advantages of the InternetThe Internet provides many facilities to the people. These includeSharing Information

2. Collection of Information

3. News

4. Searching Jobs

5. Advertisement

6. Communication

7. Entertainment

8. Online Education

9. Online Results

10. Online Airlines and Railway Schedules

11. Online Medical Advice

DisadvantagesAlthough Internet has many advantages but it also has some disadvantages. The main disadvantages are:

Virusesnothing but a program which disrupts the normal functioning of your system.

2. Security Problems

3. Pornography This is perhaps the biggest threat related to childrens healthy mental life. A very serious issue concerning the Internet.

4. Filtration of Information

5. Accuracy of Information

6. Wastage of time

7. Spamming refers to receiving unwanted e-mails in bulk, which provide no purpose and needlessly obstruct the entire system.

INTRANETAn Intranet is like a private Internet that only your employees can access. Over an Intranet employees can: Communicate via e-mail

Share files, online forms, and applications

Share databases, schedules, and calendar resources

Receive company-wide broadcasts Place orders locally or remotely

An Intranet improves the flow of information within an organization by streamlining internal communications and information sharing

Advantages of Intranets Implementation benefits

Fast, easy, low-cost to implement Based on open standards Connectivity with other systems Many tools available Scalable

Usability benefits

Easy to learn and use Multimedia Single interface to information resources and services

Organizational benefits

Access to internal and external information Improves communication Increases collaboration and coordination Supports links with customers and partners Can capture and share knowledge

Disadvantages of IntranetsManagement concerns

Management fears loss of control Hidden or unknown complexity and costs Potential for chaos

Security concerns

Unauthorized access Abuse of access Denial of service

Productivity concerns

Overabundance of information Information overload lowers productivity Users set up own web pages

What Is an Extranet?An Extranet is a secure, private network that extends company applications over the Internet. Only selected customers, suppliers, and partners can access these Extranet applications.

Extranets can provide a competitive advantage for small businesses by extending the use of key company applications to customers and suppliers and by enabling them to engage in e-commerce.Access to company information like forms, product documentation, and training schedulesby selected outside parties

Online catalogs with customer-specific pricing levels

Online order entry, order status, and shipping schedule look-up

Online support and customer service New product and service announcements via web pagesSecure e-mail exchange with customers, vendors, and business partners In addition, an Extranet's robust security prevents unwanted intrusions.

Advantages

Extranets can improve organization productivity by automating processes that were previously done manually (eg: reordering of inventory from suppliers). Automation can also reduce the margin of error of these processes.

2. Extranets allow organization or project information to be viewed at times convenient for business partners, customers, employees, suppliers and other stake-holders. This cuts down on meeting times and is an advantage when doing business with partners in different time zones.

3. Information on an extranet can be updated, edited and changed instantly. All authorised users therefore have immediate access to the most up-to-date information.

4. Extranets can improve relationships with key customers, providing them with accurate and updated information.

Disadvantages

1. Extranets can be expensive to implement and maintain within an organisation (eg: hardware, software, employee training costs) - if hosted internally instead of via an ASP. 2. Security of extranets can be a big concern when dealing with valuable information. System access needs to be carefully controlled to avoid sensitive information falling into the wrong hands.

3. Extranets can reduce personal contact (face-to-face meetings) with customers and business partners. This could cause a lack of connections made between people and a company, which hurts the business when it comes to loyalty of its business partners and customers

ReferencesGary Shelly, Thomas Cashman, & Misty Vermaat (2004). Discovering Computers 2004: A Gateway to Information. (Complete Edition). Chapter 1 & 2Lary Long & Nanacy Long (2003). Computers: Information Technology in Perspective. (Eleventh Edition). Chapter 2