Transcript Computer Networks at Key Stage 2 (The Internet, HTML, Search

Insert photo of Internet
Video about what the Internet is from uni hnagout?
Show Barefoot if time?
Computer Networks at Key
Stage 2
(The Internet, Search Engines, LANs and HTML)
Introductions
Jon Chippindall
[email protected]
Jodie Hutchings
What is the internet?
The internet is a vast network of
computers and other devices
connected together across the
planet. The internet is the
hardware.
Let’s learn a bit more about the
different connected devices that
make up the internet.
What is the WWW?
http://bbc.in/1zhOl3B
What are clients?
Clients are computers setup to
access services through the
internet. For example, we use a
client to view web pages, videos
or read emails.
Examples of clients include PCs,
laptops, mobile phones, some
TVs, games consoles and tablet
devices.
Client
Client
What are routers?
Routers are devices which help
information get to where it needs
to be across the internet. They
route it.
To help routers send the
information to the correct location,
all devices on the internet have an
internet protocol (IP) address.
Router
What are servers?
Servers are computers setup to
provide internet services, such as the
world wide web, e-mail or online
games.
Some of these computers are web
servers - they store information in
web pages which is called the
WWW.
There are also domain name
servers (DNS), which we’ll learn
more about next.
Server
Modelling the internet
Server
Router
Client
Router
RouterRouter
Router
Server
Server
Step 1
The web pages available to view are:
www.barefootcas.org.uk
www.youtube.co.uk
www.computingatschool.org.uk
Client computer asks for the the web
page that they want to view. E.g.
Write down the message ‘Can I have
the IP address of
www.barefootcas.org.uk please?’
Step 2
Routers routes (hands) the message to
the server holding the Barefoot web page
using its IP address. The message also
contains the client’s IP address.
The server holding the web page could
be located anywhere across the world.
Cables that run underground and under
the sea help carry the message between
countries.
Step 3
The server receives the message and
retrieves the web page from its memory.
It then prepares to send the web page back
to the client. However web pages are too
big to send in one piece, so it is broken
down into packets of data each labelled
with the client’s IP address.
These packets of data are sent back to the
client. Sometimes they take different routes
across the internet.
Step 4
Once all the packets of data have
reached the client, the computer reorders
them and the browser constructs the web
page for the user to view.
KS 2: use search technologies effectively, appreciate how
results are selected and ranked
Create a ‘webpage’ about London
Include:
- A URL e.g. www.allaboutlondon.com
- A title
- Paragraphs of information
- Subheadings
- If you have time, some images
Who will rank top?
Add visualization of page rank?
Local Area Networks
There are two types of network:
● LAN (Local Area network) - Connected over a small geographical area (school network)
● WAN (Wide Area Network) - Connected over a large geographical area (Internet)
Network Hunt
Clients (PC, laptop, tablet), server, main
hub/switch, printers, wifi points
Human LAN
● Request a webpage
● Print a webpage
● Create and save a document
● Open a document on a
different computer
HTML – the language of the web
Igniting curiosity…
HTML is a language.
HTML is made up of ‘tags’ that tell the computer how to display the
information.
<thing>the thing goes
here</thing>
Tags are surrounded by <> symbols.
End tags have a / before the word.
HTML Tags:
<p>A Web page starts with some HTML
tags, and ends with a few more.</p>
<img src="picture-of-something.jpg">
What could <p> mean?
What could <img ...> mean?
HTML Tags
Can you match the code
to the examples?
Can you make this?
This is an example
<p>This is an <b>example</b></p>
Can you make this?
This is an example
Can you make this?
<h1>This
is an
example</h1>
Can you make this?
This is an example
<p>This is an <i>example</i></p>
Can you make this?
This is an example
<p><b>This</b> is an <i>example</i></p>
X-Ray & Thimble