Networking Hardware – JSS3 Computer Hardware & GSM Repair Lesson Note (Second Term)

Networking hardware is the set of devices that connect computers and direct data between them on a network. The three main ones are the hub, the switch and the router.

Behavioural objectives

1. Define networking hardware and say why networks need it.
2. Describe how a hub, a switch and a router each handle data.
3. State the main disadvantage of a hub.
4. Explain the difference between a Local Area Network and the Internet.
5. Choose the correct device for a given networking job.

What is networking hardware?

Networking hardware is the equipment that carries data between computers and decides where the data goes.

• Computer network: two or more computers connected so that they can share information.
• Port: a socket on a device where a network cable is plugged in.
• Data: the messages, files and web pages that travel across a network.
• Middlemen: computers cannot send data to each other without help, so networking hardware directs the data.

Why do networks need networking hardware?

Networks need hardware to make sure each message reaches the right computer without getting lost.

• School example: in a school of 500 students, if everyone shouts at once, nobody hears anything.
• The need: when Student A sends a message to Student B, it must arrive without bothering Student C.
• The solution: hubs, switches and routers organise how data moves.

What are the three main types of networking hardware?

There are three main types of networking hardware: the hub, the switch and the router.

1. The Hub: the loudspeaker.
2. The Switch: the smart connector.
3. The Router: the traffic warden.

What is a hub?

A hub is a simple device that sends any data it receives to every computer connected to it.

• Appearance: a small box with many ports for cables, like a switch.
• Intelligence: it is the old-fashioned way of connecting computers and it is not smart.
• How it works: it does not check who the message is for. It broadcasts (shouts) it to every connected computer.
• The problem: it creates a lot of noise or traffic. With 10 computers connected, 9 receive a message they did not ask for.
• Result: the network becomes slow.

What is a switch?

A switch is a smart device that sends data only to the computer that needs it.

• Appearance: a small box with many ports, like a hub.
• MAC address: a unique “name” built into each computer’s network card. The switch learns the MAC address of every connected computer.
• How it works: it reads the address on each message and sends it only to the target computer.
• Benefit (speed): less unwanted traffic, so the network is faster.
• Benefit (security): other computers on the network do not even know a message was sent.
• Where it works: inside a single room, school or office, which is a Local Area Network (LAN).

What is a router?

A router is a device that connects one network to another, such as a home or office network to the Internet.

• Local Area Network (LAN): computers connected inside one room, building or office.
• The Internet: the large worldwide network outside your own LAN.
• Main job: the router links your LAN to the outside world.

The post office analogy

• The switch: like the messenger inside an office building who carries letters from Room 1 to Room 2.
• The router: like the Post Office. It reads the address on the envelope and decides if the letter stays in the city or goes to another country.

What are the key roles of a router?

1. Joining networks: it connects your home network to your Internet Service Provider (ISP), such as MTN or Airtel.
2. Assigning IP addresses: it gives every device in your house a digital “home address” so they do not get confused.
3. Security (firewall): it acts like a gatekeeper, so bad people on the Internet cannot easily enter your private computers.

How are the devices arranged in a simple network?

In a typical network, computers connect to a switch, the switch connects to a router, and the router connects to the Internet.

What is the difference between a hub, a switch and a router?

A hub sends data to everyone, a switch sends data to one target computer, and a router sends data between networks.

Which device should you use for which job?

Choose the device by the job: a switch for sharing inside a room, a router for the Internet.

• Switch: use it to connect many computers in one room so they can share a printer or files.
• Router: use it when you want those computers to browse the Internet.
• Hub: avoid it in modern networks because it wastes time sending data to everyone.

Evaluation

1. Why is a switch considered “smarter” than a hub?
2. Which device connects your home network to the Internet?
3. In a school computer lab with 20 computers, which device is best to connect them all together?
4. What is the main disadvantage of using a hub?
5. State two key roles of a router.

Assignment

Draw a simple network for a small school computer room with five computers, one switch and one router connected to the Internet. Label each device and write one sentence on what it does.