Activity 1
5 minutes to discuss and feedback
on the following:
•
What devices are needed to create a
computer network?
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Introduction to the Internet
&
Wide Area Networks
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Lesson Objectives
Lesson Objectives
• Review the importance of certain learning habits for success in the
lesson
• Understand the difference between a Local Area Network and a Wide
Area Network
• Understand what the internet actually is
• Understand how data travels around the internet
Success Criteria
• ALL: Successfully demonstrate an understanding of what the internet is
and what data packets are
• MOST: Successfully explain how data travels around the internet
• SOME: Be able to explain the various parts of a data packet
Literacy – Key Words
Data Packets
These are created from the splitting up of a file when data is sent acorss the internet. It is
reassembled at the receivers’ end to reform the file.
LAN
A network over a small (local) area (building or site)
WAN
A network over a large (wide) area (town, country, the world)
Internet
The largest WAN – A network of networks spanning the world
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Learning Habits
Important Learning Habits for Success in this Lesson:
Adapting :
Reflecting and making changes
Noticing details
Empathising…
…with feelings and views
Effective use of time
Questioning:
Asking questions to get
below the surface
Imagining…
…how things could be and seeing a
range of possibilities
Listening…
…to understand
Collaboration:
Working effectively with
others
Independence:
Working effectively alone
Making links…
…and recognising
relevance
Reasoning:
Thinking rigorously,
methodically and giving
explanations.
Distilling…
…what you have learnt and
what you need to learn
Meta Learning:
Talking about how you have
been learning
Managing distractions…
…and sustaining concentration
Perseverance:
Overcoming frustration and difficulty
Imitation:
Picking up good habits
from others
Capitalising:
Using resources purposefully
Planning…
…your learning in advance
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Networking – LANs and WANs
What is a Computer Network?
Two or more computers connected
together to share information and
resources.
(this can involve physical or wireless connections, or
both)
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Networking – LANs and WANs
What is a LAN?
• A LAN is a Local Area Network.
• It is a connected set of computers and other devices.
• Each device is called a node (e.g. computer, printer, etc.)
• A LAN is installed on one site.
– Relatively small
– It is owned by the organisation
So what do you think a WAN might be then?
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Difference between a LAN and a WAN
WAN
–
–
–
Wide Area Network
Covers a large geographical
area – may be worldwide
Devices may be provided by
telecoms companies like phone
lines and satellites
LAN
–
–
–
Local Area Network
Located on one site
Owner of network owns the
network devices (cables etc)
LAN
WAN
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Wide Area Networks
• What do you think is the biggest WAN
on the planet?
The Internet
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So what is the Internet?
The internet is a massive network of networks.
A ginormous collection of connected
computers.
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The amazing connections
Billions of miles of
of the Internet
cables across the land.
Undersea cables
connecting
continents.
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Data Packets
• Files are split into millions of data packets when
sent across a network or the internet.
– Packets get sent by different routes according to
availability.
– When you send a file online, the parts of the file
might travel one way around the world and the
other parts may go in the opposite direction!
– Packets are reassembled at receiving end.
• Typical packet structure:
Error Check
Data
Packet Header
Sequence No.
Return Address
Destination Address
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The amazing way that
data is sent across the
internet
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Your Main Task Today and
HOMEWORK
Remind yourself of your target level…
…based on your target level you must pick an appropriate task.
THIS MUST BE UPLOADED ONTO MBC NEXT LESSON!
RULES
• If your target level is a level 4, you can pick any task
• If your target level is a level 5, you can pick any task – BUT NOT
TASK 1
• If your target level is a level 6, you can only pick task 3
Choice of tasks on next slides…
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Activity 3
1) Describe what a WAN is, label the ‘data packet
truck’ and describe how data is sent across the
internet.
2) Explain the difference between a WAN and a
LAN, label the ‘data packet truck’, explaining why
the ‘packet header’ information is needed and
explain how data is sent across the internet.
3) Explain the difference between a WAN and a
LAN, label the ‘data packet truck’ explaining why
the ‘packet header’ information is needed and
explain, with a diagram, how data is sent across
the internet. Finally, research why a ‘data packet’
has an error check and how it works.
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