A Brief History of the Internet

What exactly is the Internet?

Who owns it?

(hint . . . not him)

How is it used?

How many people have it?

How many pages are there??

How it works

What is a Network?

Computer

Example of a Network

NetworkPrinter

ComputerComputer Computer

Computer

NetworkServer

Share data, software, and hardware

Network – two or more connected computers

Connected with cables . . .

Telephones . . .

Or satellite (or some other communication medium).

Basic Networks: LAN vs. WAN

• LAN – Local Area Network (computers which are connected and in the same physical area)– Ex: AHS is a LAN

• WAN – Wide area Network, computers are spread over a wide area– Ex: FBISD uses a WAN

So the Internet is a network?

• Any two networks joined together are called an internetwork or internet

• The global network which serves 105 million users worldwide is the Internet

The Internet

• Worldwide group of connected networks that allows public access to information and services

• Some networks are local, some are regional, and some are national

Who owns the Internet?

• No single organization owns or controls the Internet (Advantages? Disadvantages?)

When was the Internet Invented?

And was Al Gore really there?

The Internet

• Began in late 1960s

• Networks at several universities joined to form the ARPANET (UCLA, Stanford, UC Santa Barbara, and the University of Utah)

• Funded by the Department of Defense

J.C.R. Licklider

Founding director of ARPA's Information Processing Techniques Office (IPTO)

His vision: an “Intergalactic network”

The birth of the Internet depended on several

innovations. . .

Leonard Kleinrock MIT

Packet Switching

• Takes data and divides it into packets (e-mail, file, document, or a request)

• Sends packets to destination computer

• Destination computer reassembles message

Bob Kahn and Vint Cerf

TCP/IP

TCP/IP

• Bob Kahn and Vint Cerf developed TCP (Transmission Control Protocol) in 1974

• TCP was an improvement over NCP (Network Control Protocol) which only allowed communication between computers on the same network.

• This new protocol allowed diverse computer networks to interconnect and communicate with each other

Non-Centralized Networks

Nodes can function separately or as a group

Non-centralized networks

Networks which have independent nodes

Non-centralized networks

Nodes can continue to

function even if part of the network

is damaged or destroyed

Non-centralized networks

The Internet: Original Goals: National Security

• Develop a geographically dispersed network which could function even if part was disabled or destroyed

• Create a way scientists from different locations could share information and collaborate on military and scientific projects (particularly space travel)

So if the Internet’s been around since the late

1960’s . . . How come my parents never heard of it until

1993?

Until the 1990s, the Internet was primarily used by

scientists and computer nerds.

There wasn’t much there to appeal to “normal” people . . .

Until . . . .

The First Browser

• Marc Andreesen (an undergraduate student at the University of Illinois) led a team that developed first graphic interface browser called Mosaic in 1993.

• Made it much easier for users to navigate the Internet

The First Browser

• Replaced a text-only interface with one that supported graphics and evolved to support:

•Sound

•Multimedia

•Animation

•VideoBTW: Mosiac still exists – it’s now called Netscape.

Now, everyone’s

“surfin’ the ‘net” . . .

Internet Statistics May 2004

• ~950 million users

• 275 connected countries

• Average user spends more than 17 hours per month online

The World Wide Web

• Collection of hyperlinked documents

• Web site - Internet location containing hyperlinked documents

• Web page - a hypertext document residing on an internet computer

Addressing the Internet

How to get around

Web Addresses

• A web address is called a URL (Uniform Resource Locator)

• Address will be either – an IP address

(ex: 123.1.45.112

– or a domain name (ex: www.nike.com)

Anatomy of a Web Address

Internet Addresses

• Domain names must be registered in the domain name system (DNS)

• Domain names are stored in domain name servers which look up the address

• Advantages to using a domain name?

Internet Addresses:

• International Web Sites

• Includes a country code – .uk United Kingdom – .ca Canada – .ie Ireland

Internet Addresses:

• Domestic Web Sites– .com Business – .edu Colleges and Universities – .gov U.S. Government – .int International Treaty Organizations – .mil Military – .net Network and Administrative – .org Miscellaneous Organizations

The Internet

Getting Connected

The Internet & How to Connect

• Internet Service Provider

• Online services (AOL, Everyone’s Internet, Roadrunner, SBC)

Methods of Connecting: Dial-up Modem

• Uses existing phone lines

• Speed maxes out at 56 KBPS (kilobits per second)

• Average speed runs at 33.6 KBPS

• Compression software (like WebJet) can speed up download speed a bit . . .

Methods of Connecting: Dial-up Modem

Requires: Phone lineModemWeb browser

Methods of Connecting: Dial-Up

Pros: • Least expensive• Uses existing phone

lines (so you can connect from anywhere)

Cons: • Slower access

speed• Delay to establish a

connection• Occasional

disconnections• Can interfere with

phone use

Methods of Connecting: Broadband

• General term for using existing wires (phone, satellite, cable) for your Internet connection

• Connections are “always on”

• Much greater connection speeds

Methods of Connecting: Cable Modem

• Uses same connection as cable TV

• Speed varies from 2 Mbps to 5 Mbps (megabits per second)

• Must live in an area with optical fiber cable

• Access is generally $30 - $50 per month (can be bundled with other cable services)

Methods of Connecting: Cable Modem

Requires: Cable connectionCable modemEthernet connectionWeb Browser

Alternate Methods of Connecting: Cable Modem

Pros: • Higher speeds• Always available• Doesn’t interfere

with phone use • Reliability of service

Cons: • When several

people in the same neighborhood are sharing the same line, access speeds can go down

• Must live in a cable-ready area

Alternate Methods of Connecting:

Digital Subscriber Line (DSL)

• Available from phone company

• Speeds up to 1.5 Mbps

• Access costs $30-$50 per month (can be bundled with other phone services)

Methods of Connecting: DSL

Requires: DSL connectionFilters to separate data signal from voice

signalDSL modemEthernet connectionWeb Browser

Alternate Methods of Connecting: DSL

Pros: • Faster speeds• Always available• More reliable

connection

Cons: • Speed and reliability

of connection depends on your distance from provider

The Internet

Other applications

E-mail: In the beginning

• E-mail was adapted for the Internet by an Engineer named Ray Tomlinson in late 1971.

• He used the format username@domain, because – The @ symbol was rarely used.– He liked the implication that the user was “at”

a different location.

E-mail: Keep in Mind

• Must have an ISP

• Mailbox is stored on the server of the ISP

• When you connect, messages are downloaded to your computer

Benefits of E-Mail

• Faster than traditional mail

• Can send electronic documents, pictures, video

• Easier to send to large groups

• Keeps a record of message for sender

• Saves paper (in theory)

Drawbacks of E-Mail

• Spam

• Less formal

• Some folks don’t check e-mail regularly

• Systems go down

• Messages "lost in cyberspace"

• Changes people’s expectations of response time

Tips for Electronic Communication

• Never send chain letters through the Internet!

• Be professional and careful what you say about others. E-mail is easily forwarded

• Be careful when using sarcasm and humor.

• You may use emoticons and Acronyms. • Remember how easy to is to forward

messages – be careful what you say!

Tips for Electronic Communication

• Never assume your e-mail is private. Never send something you would mind seeing on the evening news.

• Keep paragraphs and messages short and to the point

• Capitalize words only to highlight an important point or to distinguish a title or heading. Don’t SHOUT!

Newsgroups

• A newsgroup is a collection of news and discussion groups

• A newsgroup operates as if it were a bulletin board devoted to a particular subject

• Older newsgroups require a newsreader to read messages (most new browsers have built-in newsreaders and many new bulletin boards use web technology)

Newsgroups

• Some newsgroups are supervised by a moderator who reads each posting before it is posted to the newsgroup

• FAQs prevent new newsgroup users, called newbies, and others from asking the same questions over and over

• Some newsgroups allow anyone to post, while some require users to register and obtain a password

LISTSERV

• Subscribe via e-mail

• Periodically, messages on a given topic will be e-mailed to your mailbox

• Check your e-mail often!!

Newsgroups vs. Listserv

• Newsgroups allow you to choose what messages you want to read, Listserv e-mails all messages to you

• Can browse or “lurk” at a newsgroup, but you must provide an e-mail address to be part of a listserv

Browsers sometimes have trouble accessing newsgroups, but e-mail is e-mail . . .

Chat Rooms/Instant Messaging

• Becoming one of the most popular Internet applications

• Allows users to communicate in real-time• Can participate in a general discussion or

have a private discussion with one or more people

• Some people maintain “buddy lists” and can be alerted when their friends are on-line

Chat Rooms

• Because of the speedy typing required, many people most participants use lots of abbreviations, acronyms, and emoticons

Emoticons (some examples)

• :-) happy • ;-) winking • 8-) glasses or

really paying attention

• >:-( angry (or goat-man)

• (:-) bald • :-o surprised • :-x sour

• :-p sticking tongue out

• {:-) eyebrows or hair parted in middle

• (:-( sad bald man • (:-* kisses • (:-1 ambivalent • (:-c ?

Acronyms/Abbreviations

• BFN - bye for now

• BTW - by the way

• IMHO - in my humble opinion

• LOL - laughing out loud

• ROTFL – rolling on the floor laughing

• TTFN - ta ta for now

• TYVM - Thank you very much

Acronyms/Abbreviations

• BRB – Be right back

• GMTA – Great minds think alike

• AFK – Away from keyboard

• HTH - hope this helps

• TIA – thanks in advance

• GTG – got to go

Tips for Chat Room Conversations

• Realize that no one may be who they say they are

• Never ever ever give personal information to people in a chat room

• Never agree to meet (in real life) anyone you “meet” in a chat room

• If you receive any inappropriate communication, notify the moderator of the chat room and your parents (or other adult)!!

Blogs

• Short for “web logs”

• Online journals or diaries

• Lots of people from celebrities to political activists post blogs . . .

Podcasts

• Online “broadcasts” available via subscription or by download

• So named in honor of the king of mp3 players . . . The iPod

• Available on a variety of topics

File Transfer Protocol (FTP)

• Allows the exchange of files between computers on the Internet

• Files can be text, graphic, sound, video, or program files

• Some sites limit file transfers to those with permission

• Some sites allow "anonymous FTP" • Must download the file before it can be viewed • Files are generally compressed

Advantages of FTP

• Provides access to files, sound, video, and programs

• Easy to use

• Can use Archie to search a wide range of sites

Disadvantages of FTP

• Material may be pirated or copyrighted

• Can pick up computer viruses

• Might need a decompression program

• Difficult to tell if information is useful until it is already on your system

Intranets

• Internal networks which use internet and web technology

• Basic uses: directories, calendars, benefit information

• Advanced uses: project management, group scheduling, employee conferencing

Intranet Concerns

• Security

• Access

• The more users, the more concerns

Security and the Internet

Security

• Any time you open your computer up to the Internet, you open it up to the possibility of an intrusion

• In other words, the world you want to access may be interested in accessing you back . . .

Firewall

• General term for hardware or software used to restrict access to data on a network

• Used to restrict access to resources and data

Proxy Server

• Computer used to separate two networks (generally yours from the Internet)

• Monitors and controls access to resources (so it can act as a firewall)

• Can be used to Cache or store a copy of a page in local storage

Do I need a personal firewall??

• Do you have broadband (cable, DSL) access?

• Do you use Windows and Outlook?• Do you routinely access files remotely via the

Internet?• Do you operate a web server?• Systems are never 100% hack-proof, but you

should at least make it tough on them

How to protect yourself:

• Use virus protection software

• Keep Windows, your browser and email software up to date

• Have your ISP scan your email for viruses and junk mail (spam).

• Back up your data files on a regular basis

• Keep all passwords secure

How to protect yourself:

• Never send your passwords via e-mail to anyone (even if they claim to be your ISP – your ISP knows your passwords, they don’t need to ask you).

• When you are not accessing the Internet, disconnect the network cable from your computer.

How to protect yourself:

If you just take some simple precautions, you can help protect your system. Even a minimal delay may be enough to persuade hackers to move on to the next victim.