Wi-Fi that stops at the stairs
A small firm has two floors. The Wi-Fi is strong downstairs. Upstairs, it drops to one bar.
The owner buys a small box for £30 and plugs it in halfway up the stairs. Sometimes it helps. Sometimes it makes things worse.
Why? You need to know which box does which job.
Key words
| Word | What it means |
|---|---|
| Network | computers and devices joined together so they can share data |
| Packet | a small piece of data sent over a network |
| Router | a device that passes packets between networks |
| Switch | a device that sends data only to the right port |
| Hub | a device that copies all data out of every port |
| Bridge | a device that joins two parts of a network together |
| Access point | a device that gives Wi-Fi to a wired network |
| Range extender | a device that repeats a Wi-Fi signal to reach further |
| Modem | a device that turns data into signals a phone or cable line can carry, and back |
| Media converter | a device that changes one kind of cable signal into another |
| Signal | the electricity, light or radio waves that carry data |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can describe hubs, bridges, access points, range extenders, modems and media converters, and choose the right one for a job.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Hubs and bridges
A hub is a simple box. Data comes in on one port. The hub copies it out of every other port. It cannot tell who the data is for.
So everyone hears everyone, and the network gets busy and easy to spy on. Hubs are old and rare now. A switch replaced them.
A bridge joins two parts of a network into one. It learns who is on each side and passes data across only when needed.
Access points and range extenders
An access point (AP) gives Wi-Fi to a wired network. A cable runs from the AP to a switch. Devices join the AP by radio.
A range extender has no cable. It listens to the Wi-Fi signal and repeats it further away. This is easy to fit, but it often halves the speed, because it listens and repeats on the same radio.
For a big building, use several APs with cables.
Quick check
Have a go
Quick check
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.