Networking Setup SS2 Computer Hardware & GSM Repair Lesson Note

Class: SS2

Subject: Computer Hardware and GSM Repair

What is a Network?

In the old days, if you wanted to give a file to a friend in the next room, you had to save it on a flash drive and walk over. That is called a “Sneaker-net” (because you used your sneakers to walk!).

A Computer Network is a group of computers connected together so they can share data instantly. Whether it’s through a physical wire or through the air (Wi-Fi), the goal is the same: Communication

Local Area Network (LAN): The “Room” Network

A LAN is a network that covers a small area, like your school computer lab, your home, or a single office building. It is the fastest and most secure type of network.

The “Ingredients” for a Wired LAN:

1. Ethernet Cables (CAT6): These are the blue or grey “umbilical cords” that plug into the back of the computer.
2. The Switch: This is the “Post Office.” Every computer plugs into the switch. When Computer A sends a file to Computer B, the Switch makes sure it goes to the right desk.
3. NIC (Network Interface Card): The actual “plug” on the back of your computer where the cable goes.

Wi-Fi: The “Invisible” Network

Wi-Fi (Wireless Fidelity) uses radio waves to send data through the air. It’s convenient because you don’t need messy cables, but it can be slower than a wired connection.

How it Works:

• The Router: This is the “Radio Station.” It takes the internet from the wall and “broadcasts” it into the room.
• The SSID: This is just a fancy name for the Network Name (e.g., “School_Staff_WiFi”).
• Security (WPA2/WPA3): This is the “Lock” on your Wi-Fi. Without a password, anyone on the street could use your data!

Setting Up a Basic Network (Step-by-Step)

Step 1: The Central Point Place your Router or Switch in the middle of the room. If it’s a Wi-Fi router, keep it away from thick concrete walls or metal cabinets, as these block the “invisible” signal.

Step 2: Connecting the Devices

• For Wired: Plug one end of the Ethernet cable into the computer and the other into the Switch. You should see a tiny green blinking light—that means “Life!”
• For Wireless: Turn on the Wi-Fi on your laptop or phone, find the SSID, and type in the password.

Step 3: IP Addresses (The “House Number”) Every computer on a network needs an IP Address (e.g., 192.168.1.5). Most routers give these out automatically using a system called DHCP. It’s like a landlord giving every room a number so the mail doesn’t get lost.

Network Troubleshooting: “Why is it slow?”

When the network “goes down,” don’t panic! Follow this “Logic of Three”:

1. The “Physical” Check: Is the cable plugged in all the way? Is the Router turned on? (Check the lights!)
2. The “Power Cycle” (The Magic Fix): Turn the Router off, wait for 30 seconds, and turn it back on. This clears the “brain” of the router and fixes 80% of problems.
3. The “Ping” Test: On your computer, open the Command Prompt and type ping google.com.
   1. If you see “Reply,” the internet is fine.
   2. If you see “Request Timed Out,” the connection is broken.

Summary Table: Wired vs. Wireless

Student Practical Activity

“Today in the lab, look at the back of your computer. Can you find the Ethernet Port? Is the light green or orange? If you are on a laptop, click the Wi-Fi icon and see how many ‘bars’ of signal you have. Try moving closer to the router—does the signal get stronger?”