The Internet at Home and in the Workplace

Chapter 8

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Objectives

Briefly describe the history of the Internet Explain what is needed to get on the

Internet Describe generally what an Internet service

provider does Describe the rudimentary functions of a

browser Describe how to search the Internet

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Objectives

List and describe the non-Web services of the Internet

Describe the various types of e-commerce Discuss e-commerce payments and taxes Describe how advertising is done on the

Internet Describe what an intranet is and how a

business uses it

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History of the Internet

Government and Universities over 30 years Who’s connected today?

Individuals Educational institutions Government/Military/Police Research Medical Businesses Everyone!

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The Early Years

1969 – US Department of Defense and Rand Corporation

Origins Cold War – fear that a bomb could demolish computing

capabilities Several computers, geographically dispersed, networked

together Plan – if one computer was disabled, others could carry on

using alternative communication routes

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The Early Years

Many WANs and LANs were installed, but machines on the WANs could not access information on the LANs.. Remote access was separated from local access

A single cohesive network was desirable.

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The Early Years

US Department of Defense had a similar scenario – lots of autonomous networks that could not interoperate

The DoD funded network research in the early ’70s through (D)ARPA creating various network technologies, including a research WAN called ARPANET.

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The Early Years

ARPANET allowed researchers the opportunity to build a working test-bed for networking ideas. Solved incompatibility issues Solved interoperability issues Created an internetwork of LANs and the WANs

The Internet is born

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The Early Years

ARPANETBackbone

UCLALAN

MITLAN

UCBLAN

DARPALAN

G1

G2

G4 G3

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The Early Years…

Internet Software Internet Protocol (IP)

Provides basic communication Handles the addressing and routing

Transmission Control Protocol (TCP) Provides services for applications to communicate Packetizes message, reassembles message at the

destination The “TCP/IP Internet Protocol Suite”

aka TCP/IP

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The Early Years

ARAPA placed the research and software into the public domain. All information was freely available to any person

or vendor, allowing them to create devices or networks that would interoperate with the Internet technology.

Improvements were documented and made publicly available.

This philosophy is called an Open System

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The Early Years

Internet documentation On-line and accessible from the Internet Reports for improvements to the Internet were initially a

two step process Request for comments (RFC) went out first Internet Engineering Note came out with the comments

as the final report. Today the RFC remains as the definitive documentation for

the Internet On-line at www.faqs.org/rfcs/

Also www.ietf.org/rfc.html

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The Early Years

The UNIX operating system Built at Bell Labs in the early ’70s UNIX given to universities to study UC Berkeley team added LAN software

Distributed to others via the Berkeley Software Distribution (BSD) and became known as BSD UNIX (The ancestor of today’s Free BSD)

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The Early Years

ARPA negotiated with UCB to add the TCP/IP suite to the BSD UNIX release. Gave large number of universities access to

study networking, and deploy it in their departments.

1982 the US Military chose the Internet as its primary communication system.

1983 the ARPANET began running TCP/IP exclusively.

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The Early Years

Incredible growth from day one.. In 1982 ~200 machines were connected By 1983 the number had doubled With growth comes the problems..

Static lists of machines need updated Limited memory space … Software updates..

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The Early Years

The Computer Science Network (CSNET) Sponsored by NSF in early `80s

Goal was to connect every Computer Scientist in the country over one network.

CSNET was deployed using TCP/IP and the Internet By mid 1980s most major university and research labs

were connected to the Internet Graduate students began to investigate the details of

these new technologies, and include them in their research topics.

Developed new applications Extended the technology

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The Early Years

The IAB (Internet Activities Board)(Now known as the Internet Architecture Board) Original controlling body to coordinate TCP/IP

research and Internet development. Chairman – Internet Architect RFC Editor Formed volunteer task forces to solve problems

Task forces generated new RFCs

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The Early Years

The IETF (Internet Engineering Task Force) Originally chartered for short-term Internet

development. Now is responsible for most of the Internet

technical development Working groups meet and create the RFCs

Manet, ipsec, tcp…

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The Early Years

NSFNET NSF recognized the importance of the Internet to

the scientific community. Interconnected the supercomputer centers

around the US with a TCP/IP WAN Proved useful, but small NSF looked for ways to improve the ARPA Internet

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The Early Years

The NSFNET Backbone 1988 WAN established as main backbone of the

Internet MCI – long distance transmission lines IBM – dedicated computers and software MERIT – network operation

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The Early Years

The ANS Backbone (Advanced Networks and Services) Consortium of MCI, IBM & MERIT

Allowed the government to begin privatization of the Internet

1992 – WAN was built to serve as the Internet backbone ANSNET, 30 times NSFNET capacity

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The Early Years

Exponential growth …….

01000000020000000300000004000000050000000600000007000000080000000

1983 1987 1991 1995 1999

ComputersConnected

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Growth of Internet

Growth in host computers 72 million in 2000 162 million in 2002

Growth in users worldwide 567 million in 2002 780 million projected in 2003

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The Early Years

By 1999, the Internet was growing so fast that, on average, a computer was added to the Internet every second – and the rate continues to increase.

An interesting fact: At any time from 1983 through 1999, approximately

half the growth of the Internet occurred in the previous 12 months…

So, after you have been “on” the Internet for only one year, you will have had more experience than half the other users….

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The Early Years

Growth – Good and Bad Good for vendors Bad for the IETF

Predictions of imminent collapse March 1993, Summer ’97

Technology improvements have kept up with bandwidth and switching speeds required.

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The Early Years

The Hard limit – Address space The IP protocol is limited to a number contained in

4 bytes (32 bits)…

Byte 0Byte 1Byte 2Byte 3

•This limits the number of possibilities to 232 = 4,294,967,296

•There are solutions – IPv6

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The Early Years

Summary The Internet began as an ARPA research project. The TCP/IP protocol software was developed to

make the Internet operational. The Internet is an Open System, with the

technology freely available to all. The Internet documentation is available on-line in

the form of reports known as RFCs.

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The Early Years

Summary (continued) BSD UNIX distributed TCP/IP suite freely to

universities in the early 80s 1982 US Military adopted TCP/IP as primary

communication standard Exponential growth from its inception IAB formed to coordinate development IETF - major technical development body

Working groups

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The Early Years

Summary (Continued) 1988 – NSFNET Backbone 1992 – Privatization (ANSNET) Exponential growth from its inception

Half of the users today have been there less than one year……

IP Address 32 bit limitation

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Tim Berners-Lee

Worked at CERN lab in Geneva Thought his work would be easier if he

could link to colleagues’ computers Envisioned a network of computers

much like a spider web Used links to transfer data from one

site to another location CERN site considered the birthplace of

the World Wide Web

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Marc Andreessen

Developed the first graphical browser Called Mosaic Led to Netscape Navigator

Could display attractive images and a graphical interface permitting users to click on pictures as well as text

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Internet Links

A link on a Web site is easy to see Either underlined and

colored text or an icon Clicking the link transfers

data from that site to the user’s computer

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Browser

Interface software used to explore the Internet Early browsers were text-only Mosaic was the first graphical

browser Graphical browsers combine

ease of links with attractive graphical interface

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A Little About the Technology

A message sent over the Internet is divided into uniformly sized packets Each packet labeled with its destination address

Transmission Control Protocol/Internet Protocol (TCP/IP) TCP creates and reassembles packets IP handles addressing

Ensures that packets are routed to their ultimate destination

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The Internet Service Provider and the Browser An Internet service provider

(ISP) provides the server computer and software to connect to the Internet Online service, such as America

Online, includes Internet access, Internet service, and a browser

When you connect to the Internet, the browser displays a home page

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Menus and Buttons

Menu – a series of choices normally laid out across the top of the screen Called pull-down menus Each initial choice gives lower-level choices

Buttons can be used to invoke commands Screen tip – a small text message that

appears when you rest the cursor over a button

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Uniform Resource Locator (URL)

The complete, unique address of a Web page Web page URL begins with http

HyperText Transfer Protocol – allows communication by using links to transfer data between sites

Domain name – address of site’s host computer Last part of domain name is called a top-level domain Identifies country or purpose of organization

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URLUniform Resource Locator

Unique address of a web page or file on the Internet

Case-sensitive

http://domain-name.top-level-domain/last-section

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Processing RequestsURL

User enters a URLUser computer sends request to the ISP

server ISP server sends request across networks of

TCP/IP computersDestination site is reachedContent is transmitted back to your computer

(process in reverse)

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Plug-ins

Software that increases browser functionality Most downloaded from their own Web sites

Once downloaded and installed, the browser can handle the new features

Most enhance a site’s audio-video experience Shockwave permits viewing sites that include quality

animation Adobe Acrobat Reader displays and prints documents

created in Portable Document Format (PDF) form

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Web Page Programs

Small programs can be downloaded to run in your browser Allow Web pages to perform many tasks Allow dynamic interaction

Come in several forms Scripting languages

Produce instructions to be interpreted and executed by your browser

JavaScript and VBScript are most common Programs embedded in Web page

Java applets and ActiveX controls are most common

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Programming

Java Write software that is machine independent Programming language

Dancing iconsSound clipsFlashing messagesBanners that scroll

Applets – Permits dynamic web pagesDisplay animationsReceive inputPerform calculations

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Programming

ActiveX ControlsCapabilities similar to Java

Browser must be enabled to support applets / ActiveX Controls

Security issues

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Wireless Internet Access

Use handheld devices such as pagers, PDAs, or pocket computers to access the Internet

Wireless Application Protocol (WAP) – convert Web pages into a format more compatible with limited capabilities of handheld devices

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Wireless Internet Access

Supports mobile handheld devicesText pagersPDAsPocket computersWeb-enabled cellular phones

ApplicationsE-mailChecking weatherMaking airline reservations

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Searching the Internet

Search Engine – lets a user specify search terms

Search engine builds database of sites that match those terms

Uses spider software (or bots) to build database

Metasearch – searches search engines and builds comprehensive list

Internet directory – database is developed by human researchers rather than spider

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Request same search using different engines yields different results

Databases built independently Size Content Search methodology Pages may be submitted by the owner

Metasearch – automatically puts the same request to several search engines

Processing Requests: Search Engine Database

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Processing Requests: Search Engine Limitations

Index only a fraction of the Web Approximately 20% to 33% of sites More web pages added daily Solution

Same request to several search engines Metasearch

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Not Perfect

Unregulated Useless web sites Misinformation and misstatements on web

sites Concern over government censorship Security & Privacy Issues

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Newsgroups

Usenet – an informal network of computers Allows posting and reading of messages Typically focuses on specific topics Requires a newsreader

Some are moderated Messages sent to a moderator, who determines whether

the message is appropriate Prevents users from attacking other members and

prevents inappropriate material from being posted

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File Transfer Protocol (FTP)

A protocol for transferring files among computers

FTP servers maintain collections of downloadable files Downloading can often be done anonymously,

without logging in Many FTP servers can be accessed through

Web browser

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Telnet

A protocol that allows remote users to log onto a host computer Users use their own PCs Users log in over the Internet Users’ experience is the same as if they were

sitting at the host computer’s local terminal Remote user typically has to have a user ID

and password

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E-Mail

The most commonly used feature of the Internet

Network provides mail server E-mail client software on your computer

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Mail Server

Collects and stores messages in mailbox E-mail address consists of user name,

followed by @ symbol, then domain name of mail server

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E-Mail Client Software

Allows you to manage your e-mail messages Features

Address books The ability to attach files

Some e-mail servers block all attached files Filters

Direct incoming e-mail to specific folders Block spam

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IRC: Internet Relay Chat

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Not Perfect: Social Issues

Behavior problems Who is out there? What are they doing?

Netiquette Suggestions for appropriate behavior Example: TYPING IN CAPS is shouting

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The World of E-Commerce

Electronic commerce - buying and selling over the Internet

Three forms Business-to-consumer (B2C) Business-to-business (B2B) Consumer-to-consumer (C2C)

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Business-to-Consumer

Businesses selling goods to consumers Has received the most media attention Estimates of U.S. online sales

$48 billion in 2002 Projected $130 billion by 2006

Several models Pure-play Bricks-and-clicks Flips-and-clicks

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Pure-Play Model

Companies operate exclusively over the Internet Some have their own

warehouses Others relay orders to

manufacturer or wholesaler Examples include

Amazon.com and etoys.com

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Bricks-and-Clicks Model

Traditional retail outlets that have established a Web site Name is a play on “bricks and

mortar” Examples include J.C.

Penney and Macys Well-known brand names Loyal customer base

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Flips-and-Clicks Model

Traditional mail-order retailers that have established Web sites

Catalogs placed on Web sites Allow customers to replace

flipping pages with clicking links and icons

Examples include L.L. Bean and Land’s End

Allows retailer to reach many more customers

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Business-to-Business

Businesses selling to other businesses Has not received much media attention Estimates of worldwide sales

$1.9 trillion in 2002 Projected $8.5 trillion by 2005

Internet exchanges are being developed to provide electronic marketplaces

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Internet Exchanges

Create a marketplace Bring together many buyers and

sellers Advantages

Reduced costs of procurement (purchasing)

The ability to consider many suppliers

Potential concerns Security Antitrust concerns (possible

price-fixing)

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Consumer-to-Consumer

Takes place on online auction sites

Make buying and selling unique items easy Your item is visible to anyone

in the world with an Internet connection

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Payments and Taxes

E-commerce payments Some people are leery of submitting credit card

information online Secure Sockets Layer (SSL) protocol provides a secure

way to make online payments E-commerce taxes

Internet Tax Freedom Act provides tax relief on Internet commerce

Commission studies the effects of taxation of Internet commerce

Act set to expire in 2005

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Internet Portals

Your first stop on the Internet Provide personalization to users

Site is customized based on information you provide

Encourages you to visit the site often

Provide referrals to other businesses

Site contains links to affiliate sites If you click on an affiliate site and

make a purchase, the portal receives a percentage of the sale

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Internet Advertising

Many advertisements on Web sites are banner ads

Originally in the shape of a long rectangle

Require the user to leave the current site

Other ad types Pop-over ads open a new

window on top of your current window

Pop-under ads open a new window underneath your current window

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Intranets

A private Internet-like network Internal to a certain company

Extranets allow selected customers and suppliers to have access to a company’s intranet

Easy to set up Offer many potential uses Can be linked to the Internet

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Setting up an Intranet

Easy to set up Most organizations already have a local area

network Hardware requirements Software requirements

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Hardware Requirements

Server computer handles requests Computer for storing databases and other

documents Client computers needed for access to the

Intranet TCP/IP protocols must be in place

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Software Requirements

Server must be able to process requests from other computers

Server must be able to retrieve data from computers that store it

Each access computer needs a browser

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Uses of Intranets

Users can Retrieve information such as benefits information

and job openings Submit vacation requests, applications for open

positions, etc. Employers can post employee handbooks,

corporate policies, and other information in a central location

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Virtual Private Network

Technology that uses the Internet as a channel for private data communication

Uses tunneling technology Offers many benefits over a private network

Much cheaper than dedicated lines Data is secure Turns remote network administration over to ISP

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Tunneling

Also called encapsulation Transfers data between two similar networks over

an intermediate network Data packets follow Point-to-Point Tunneling Protocol

(PPTP) Data embedded in TCP/IP packets carried by the Internet

Data packets are encoded before encapsulation When received, they are separated and returned to their

original format Provides security for data packets