Transcript 03-wired-and-wireless-network_l2_teacher

Unit 1.4 Wired and
Wireless Networks
Lesson 2
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Big Picture
• Video:
https://www.youtube.com/watch?v=EWTJKcg7Pj8
• What hardware do we need to create a LAN. How
will the computers be connected together and what
might be required to do this?
• What do we mean by the performance of a network
and why this might be important?
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Learning Objectives
• Identify the components required to create a LAN
• Describe the role of each component in a LAN
• Understand what is meant by the performance of a
network and why this is important
• Explain the factors that can affect the performance
of a network
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Engagement Activity
• How do packets travel around a network? (Practical
class engagement task)
• Have you ever been frustrated by your computer or
mobile device working very slowly. What might be
causing that to happen and what might be affecting
the performance of the network you are trying to use
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Key Words
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LAN
•
Packet
Wireless access point (WAP) •
Router
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Switch
Network interface card
(NIC)
Transmission media
Network performance
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Activity 1
• What do we mean by a packets of data?
• Why do we need to create packets of data?
• What might happen if we did not have the correct
hardware to guide the passage of the packets of
data?
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Packets
• Data transmitted over a network is broken down into
packets.
• Each packet contains the address of the sender and
the address of the receiver (IP addresses)
• Packets will also contain a sequence number
• Packets will have a time to live (how many hops
around the network they can take before they
disappear
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Hardware components
What is the role of the following hardware components
in a network?
• Wireless access point (WAP)
• Router
• Switch
• Network interface card (NIC)
• Transmission media
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Wireless Access Point (WAP)
• Allows for wireless devices to connect to a network
(either LAN or WAN)
• Includes connections through Wifi and Bluetooth
• WAPs provide Internet access in public places
(often known as Wi-Fi hotspots)
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Router
• An interconnection device used on networks to connect
two or more devices.
• Routers contain a routing table which has a list of IP
addresses and common routes for packets to take
• Routers examine packets IP addresses
• The router will apply a subnet mask to identify a network
and determine which network the packet should be
forwarded to
• If the packet is for this network – the router determines
which host to send the packet to
• Routers allow packets from different network types to be
exchanged
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Switch
• If two or more computers place a packet onto a
network at the same time – a data collision occurs
• A switch is an interconnection device that connects
two or more devices together and helps in solving
the issue of data collisions
• As a data packet arrives at the switch – its
destination address is examined and the switch
creates a direct connection to that device
• As far as the two devices are concerned there are
no other computers on the network (see example)
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NIC Network Interface Card
• A network interface card allows a computer to
connect to a wired network
• A NIC allows data packets to travel to and from a
computer
• A NIC contains a MAC address which is a physical
hardware address
• A NIC allows an Ethernet cable to be plugged into
this
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Transmission Media
• Ethernet (Cat 5e / Cat6)
• Known as twisted pair
• A networking standard
• Fibre optic
• Very fast cable but also more expensive (often used
with WAN or larger LANs)
• Coaxial Cable
• An older networking standard
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Activity 2
• Complete the worksheet by drawing lines between
the correct hardware term and definition.
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Activity 3
• Create a leaflet for a business to explain how they
can get the best out of their network.
• In it the leaflet you should explain the factors that
can affect the performance of a network and how
these can possibly be overcome.
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Plenary
• Pair testing
• Use revision cards to test your partner to find out
what they know about network components
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