- The History of the Internet 2:21
- Check your facts, your history facts that is! 4 questions
- The Big Picture 2:59
- The Big Picture 3 questions
- Clients and Servers 2:04
- Client and Servers 4 questions
- TCP/IP 3:04
- TCP/IP Protocol Suite 5 questions
- Routers and Switches 2:32
- Routers and Switches 5 questions
- Connecting to the Internet 2:57
- Your Big Picture Review 1 question
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The Big Picture
2:59The Internet is a world-wide network of computers that we use to watch videos (like this one), communicate with friends, and learn about the world. In this video learn more about the underlying technologies and protocols that run the Internet.
The Internet is a network of
independent computers and
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other hardware devices connected together.
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You can think of this as a bunch of wires
that let computers around the world
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communicate with each other.
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Connected to these wires
are forests of other devices,
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which make the Internet work like servers,
routers, and switches.
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The primary network in core routers
around the world make up the backbone of
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the Internet, and support the exchange
of Internet traffic between countries,
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continents, and across oceans.
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Because of the diversity in hardware
used all over the Internet,
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everyone needs to work cooperatively.
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The developers behind the software
used on the Internet agreed to follow
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a set of rules called protocols,
when sending and receiving information.
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Let's look at what's involved when you go
to the homepage of your favorite website.
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For the purposes of this example,
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let's say your wirelessly connected
to the Internet at your house.
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After opening up a web browser and typing
in a URL, your browser uses a special
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protocol called HTTP or
Hyper Text Transfer Protocol.
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This is a set of rules for
asking for and getting webpages.
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But there's an even more basic set of
protocols under this, called TCP/IP.
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Which is short for Transmission Control
Protocol and Internet Protocol.
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These are the rules for sending and
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receiving any data whether it's email,
webpages or files on the Internet.
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Once you initial your request
TCP IP protocols take your request,
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webpages, videos, or emails and
break them into little packets of data and
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send them in the fastest way possible.
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From client to server and back again.
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The TCP IP protocols are a fundamental
part of the internet
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which we'll learn more about
later in another video.
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After you request a web page TCP IP
send your request wirelessly over
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radio waves either to a router or
directly to a wireless modem.
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If you have a router what
was a wireless request
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is now sent along an ethernet
chord to your modem.
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Your modem then sends the packets
along a coaxial cable or
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phone line to the outside of your house
where your internet service provider or
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ISP connects you to the Internet.
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The main network made of fiber
optic cables and computers.
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Once it reaches this point your request
is now sent from one server to another
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until it reaches the server that's
hosting the website you wanted.
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Then, the webpage you requested
is returned in just the same way.
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If this all happens correctly, the packets
of data arrive, are reassembled, and
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the web browser shows you
a perfect copy of the webpage.
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Usually this happens very quickly.
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Often in just a matter of seconds.
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So the internet has one job,
letting computers and
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other devices around the world
to talk to each other.
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But accomplishing that
job is no easy task.
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In the next few videos, let's look at each
aspect of the internet in more detail.
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