the internet agenda history connecting to the internet structure of the internet foundation of...
TRANSCRIPT
Agenda
History
Connecting to the Internet
Structure of the Internet
Foundation of Modern ICT
Ban the Internet
Internet Browsers
WWW
History of the Internet• Late 1960’s, the Advanced Research Projects Agency (ARPA) of the U.S. Department of Defense begins the internet as a military project.• Government creates a network towithstand a nuclear attack across a largearea• It linked together mainframe computers to create a communication system.
Internetworking• The process of linking a collection of
networks is called internetworking. • This term is where the Internet got its
name.• The term Internet was officially adopted
in the early 1980s. • Today = the Net.
• The Internet is the collection of networks of computers and storage devices linked together by cables and/or satellite.
ARPANET, MILNET, and NSFNET• First Internet was known as ARPANET (Advanced
Research Projects Agency Network).• Used to share scientific and engineering
information, and send email.• In 1983, ARPANET split into two parts—ARPANET and
MILNET. • Various defence agencies and the military used
MILNET.• Mid-1980s, the ARPANET backbone was not fast
enough to meet the high demands of the academic and research communities• The National Science Foundation (NSF) created a
new high-speed network, NSFNET (National Science Foundation Network)
• But NSFNET did not serve businesses or individuals; only academic
ARPANET, MILNET, and NSFNET• As more individuals were using personal computers, there
was a growing demand by businesses and individuals. • So telecommunication companies, such as Bell Canada,
AT&T, and Nortel built high-speed backbones and new networks that used the same protocols as the NSFNET.• It was the beginning of Internet service providers
(ISPs)—companies that provide users with access to the Internet,
• Network quickly grew from including researchers and scientists across the country to eventually the world.
• Common uses include:• Electronic Mail (e-mail) and discussion groups• Online shopping• Information, Education & Entertainment
History of the Internet• History Of The Internet (HD)
– http://www.youtube.com/watch?v=7NpczzIsnLU&feature=related
Structure of the Internet• Consists of thousands of connected networks around the world• The underlying structure of the Internet is a set of backbone connections (major highways) and routing tools (major traffic intersections) that control the way pieces of data find their way to their destinations.
Structure of the Internet• To establish how data find their way to their destinations, a
protocol, or set of formal rules, was developed that described how to transmit data across networks.• A protocol is an agreed-upon format for transmitting
data between two or more devices. • TCP/IP (Transmission Control Protocol/Internet
Protocol) became the accepted means of communication across networks; it became the language of the Internet. • TCP/IP is a complex set of rules and procedures that
indicate how data should be organized for travel on the Internet.
• It prepares data for travel on the Internet, and then puts the pieces back together at the receiving end.
Structure of the Internet• Example: how we access the Web illustrates
how information travels on the Internet– After you key in the URL (uniform
resource locator) or web address , the address must be converted into a form that the Internet can understand.
– For web addresses, this form is a sequence of numbers or numbers and words, referred to as the IP (Internet Protocol) address. •For www.nelson.com,the IP address
is 69.32.132.85/nelson.
Structure of the Internet• How is the address converted? • The text address ww.nelson.com is sent
to the Domain Name System (DNS) server at your Internet service provider.
• This server attempts to maintain an up-to-date list of URLs
• If an address is not found on this DNS server, the server sends a request to another external DNS server until the address is found (if it exists).
Structure of the Internet• When the address is found, the server requests the web page
from its source. • After the request is made, the files (packets) that make up
the page are sent to your computer through a series of networks, routers, and gateways.• Routers- they direct traffic in appropriate directions (like
traffic officers)• If there is too much traffic moving in one direction,
they will redirect some of the traffic.• Gateways are points where information needs to be
translated into some other format for it to pass through a particular network.
• At these junctions, Internet packets will be pieced together and split up again following some other protocol or set of rules.
• Once they arrive at your computer, they will be reassembled , and display the web page.
Structure of the Internet• "The Animated Internet: How the Web Works" provides an
explanation and animation to help you understand the Domain Name System (DNS) used on the Internet. – http://www.learnthenet.in/animated-internet/how-the-
web-works/index.php• How the Internet Works in 5 Minutes
– http://www.youtube.com/watch?v=7_LPdttKXPc
Structure of the Internet• Can you imagine what the Internet looks
like? • How might a global network of networks
look? • Go to “An Atlas of Cyberspaces” and
explore the maps and graphics that represent what the Internet might look like. – http://personalpages.manchester.ac.uk/
staff/m.dodge/cybergeography//atlas/atlas.html
Structure of the Internet• Use the Conceptual link to find a map that shows the
landmarks of cyberspace from 1994 to 1995.– What are the spaces that make up the Internet, according
to this map?• Use the Artistic link to find a map that illustrates the travel of
packets on the Internet. – What do they look like? Do you think they really look this
way? • Find a map that illustrates packets speeding through a LAN.
– Why did you select this map? • Use the Geographic link to find a map that attempts to show
traffic on the Internet. – What can you conclude from this map?
• Select the Topology link, and find a map that illustrates the Internet as hundreds of interconnected pipes of various sizes. – Where on the map would you find routers and gateways?
Connecting to the Internet• The essential parts you need to connect to the Internet
are the following:• a computer• a connection device that connects your computer to
your link to the Internet (e.g., modem)• telecommunication software and protocols, often
available through your operating system• a link between you and the Internet (e.g., telephone or
cable line)• an account with an Internet service provider
Connecting to the Internet• The most common methods of connecting to the
internet are:1. Modem: Connecting through a phone line. Usually
at 56 kilo bytes per second (Kbps)2. Broadband or high-speed modem (cable or ADSL
(Asymmetric Digital Subscriber Line), commonly referred to as DSL)• Has a higher data transmission speeds therefore
it allows more data to be sent over.3. Satellite
• Coaxial TV cable connects to a modem for downloads. Uploads are transmitted either through the same modem or traditional dial-up modem
The Foundation of Modern Information and Communication Technology
• What Structural Foundations Support Modern Information and Communication Technology?
• New equipment and devices have to be developed to make advances in technology
• For this to happen, information technologies requires an infrastructure—a structural foundation—that enables the technologies to work.
The Foundation of Modern Information and Communication Technology• Some of the infrastructure, or underlying
system, for delivering information includes:• Satellites• Fibre-optic
•systems that carry information via light pulses along ultra-thin glass fibres.
•A fibre-optic cable can carry 1000 times as many telephone conversations as can a traditional wire cable
Introduction to the WebThe World Wide Web • The Internet controls
the way pieces of data find their way to their destinations.
• There are many types of data that travel on the Internet.• One type is the
World Wide Web hypertext document.
Introduction to the WebThe World Wide Web • The World Wide Web (WWW) is the total
collection of hypertext documents stored in computers connected to the Internet.
Introduction to the WebHypertext• Hypertext documents are most commonly
written in a web authoring language called HTML (Hypertext Markup Language).• It includes text and codes, which are visible
only to the web browser (e.g., Internet Explorer) and instruct the browser how to display the text.
• How does the browser know what each of the codes means? • It follows the rules or protocols established
for web browsers, known as HTTP (Hypertext Transfer Protocol).
Introduction to the WebHypertext• Hypertext documents contain hyperlinks.• link: Text or images that connect to other
pages on the web.• These links lead users to another World
Wide Web page or another place within the same document.
Introduction to the WebWeb Pages and Web Site• Each web page on the internet has a unique
address called a URL (Uniform Resource Locator) or web address• A Web page is a document on the web (could
include text, images, sounds, video)• A web site is a collection of web pages
• A website URL begins with http to tell your browser that the file being referenced by the URL needs to use certain protocols, or rules, to be interpreted a certain way (using the Hypertext Transfer Protocol or HTTP) for you to be able to view it.
Introduction to the Web• The Invention of the World Wide Web
– http://www.youtube.com/watch?v=1IQFjTnDozo&feature=related
• World Wide Web in Plain English– http://www.youtube.com/watch?v=90cfeFBid68
Surfing the WebInternet Browser• To view web pages on the Internet, users require a web browser.• A web browser is a program that will interpret hypertext documents on the Web and display them on screen.• Ex: Microsoft Internet Explorer, Netscap Navigator and Mozilla.
Internet Browser•An Internet browser is your window to the web, where you can find almost anything.•Today, the Internet is widely used for media, research, communication, shopping and entertainment. The better your browser, the more you will see and experience.•Up–to–date web browsers are equipped with the latest features and technology to simplify, accelerate and enhance your Internet experience.
•New Features Include:•tabbed browsing, •RSS feeds•voice interaction•more customizable with entertaining skins, informative and fun widgets.
Internet Browser•Modern Internet browsers know that safety is a common concern among web surfers.
•Threats include:•Viruses, spyware, phishing schemes and identity theft. •the threat of online predators •appropriateness of material for children.
Internet Browserhttp://internet-browser-review.toptenreviews.com/
Top #3-Fire Fox-Google chrome-Internet Explorer
What to Look for in Internet Browsers
•Internet browsers should have three main objectives:
•simplicity, •security and •helping you get the most from the web.
•Most browsers are free, so you can review what each browser offers and download the one right for you, or consider a couple of browsers. (You might even decide to use more than one browser—for example, one for fun and one for research.)
What to Look for in Internet Browsers
•Below are some of the criteria used to evaluate Internet browsers.
•Features SetTop–ranked Internet browsers offer many practical features that make surfing the web faster, easier and more convenient. Such as
•tabbed browsing, •thumbnail previews •integrated search engine.
•Ease of UseInternet browsers ought to be simple to use so anyone, regardless of their knowledge of computers or the Internet, will feel comfortable using the web.
What to Look for in Internet Browsers
•SecurityOne of the most important aspects of browsing the web. It should protect against
•pop–ups, •viruses•phishing frauds •allow you to clear personal information so you can feel confident while online.
•Speed & CompatibilityYour internet browser should help you surf fast and efficiently. While the speed of your computer and internet connection account for most of the speed, not all browsers are created equal in regards to how fast they startup, process HTML and JavaScript. Likewise, not all internet browsers will open all pages correctly. The best browsers will open websites quickly and properly.
What to Look for in Internet Browsers
•Help/SupportAlthough most browsers are free, quality customer support helps if you run into problems. Developers provide support through email, phone, FAQs, manuals and tutorials.
Internet Browser•How to Use Firefoxhttp://internet-browser-review.toptenreviews.com/firefox-p535-video-1.html
Curent Internet Explorer-9http://windows.microsoft.com/en-US/internet-explorer/products/ie-9/videos