The library video call that froze
Elm Park Library is made up. Its staff hold a video call with a book supplier in another town. The picture freezes, the sound jumps and the call ends.
Was it the cable, the Wi-Fi or too many people online? To fix it, you must know how connections work.
By the end of this lesson
Note
I can choose a wired or wireless connection and a type of link for a given need.
Key words
| Word | What it means |
|---|---|
| Network | devices joined so they can share data |
| Router | a device that sends data between networks |
| Sensor | a device that measures something, such as heat |
| Wired | joined by a cable |
| Wireless | joined by radio signals, with no cable |
| LAN | a network in one building or site |
| WAN | a network that links places far apart |
| PAN | a tiny network around one person |
| Bandwidth | how much data a connection can carry each second |
| Latency | the delay before data arrives |
The cells students fill in are left blank in this preview.
Starter: what you already know
Have a go
Starter: what you already know
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Wired and wireless each have strengths
A wired connection uses a cable. It is usually fast, steady and harder for outsiders to reach. But the cable limits where devices can be.
A wireless connection uses radio signals. Devices can move around and there is no cabling to install. But walls and other signals can weaken it, and it can be easier to attack.
Which connection for which job?
| Job | Better choice | Reason |
|---|---|---|
| Video calls at a fixed desk | Wired | Steady, so the picture does not freeze |
| Visitors reading on tablets | Wireless | People move and carry their own devices |
| Control of a door lock | Wired or wireless | Depends on the distance and the risk |
| Collecting readings from sensors | Wireless | Sensors are spread out |
| Nightly backup of large files | Wired | Fast and steady for big transfers |
The cells students fill in are left blank in this preview.
Check
Have a go
Check
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.