Unit 1 4 Wired and Wireless Networks Lesson

Unit 1. 4 Wired and Wireless Networks Lesson 2 © OCR 2016

Big Picture • Video: https: //www. youtube. com/watch? v=EWTJKcg 7 Pj 8 • 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? © OCR 2016

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 © OCR 2016

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 © OCR 2016

Key Words • • • LAN • Packet Wireless access point (WAP) • Router • Switch Network interface card (NIC) Transmission media Network performance © OCR 2016

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? © OCR 2016

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 © OCR 2016

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 © OCR 2016

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) © OCR 2016

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 © OCR 2016

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) © OCR 2016

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 © OCR 2016

Transmission Media • Ethernet (Cat 5 e / Cat 6) • 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 © OCR 2016

Activity 2 • Complete the worksheet by drawing lines between the correct hardware term and definition. © OCR 2016

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. © OCR 2016

Plenary • Pair testing • Use revision cards to test your partner to find out what they know about network components © OCR 2016

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