The door with a guard
A school has one main door. A guard stands there. The guard checks who comes in and who goes out.
Your school computers need a guard too. Without one, anyone on the internet can knock on every computer inside.
By the end of this lesson
Note
I can explain what a firewall (a guard for data) does and how to protect its own settings.
Key words
| Word | What it means |
|---|---|
| Network | computers joined so they can share data |
| Firewall | a device or program that allows or blocks traffic |
| Traffic | the data moving across a network |
| Rule | one instruction that says allow or block |
| Administrator | the person who looks after a system |
| Authentication | proving who you are, for example with a password |
| Log | a record of what happened |
The cells students fill in are left blank in this preview.
Starter
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Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
A firewall checks traffic against rules
A firewall sits between two networks. It looks at every piece of traffic.
It checks each one against its rules. A rule says allow or block. Allowed traffic goes through. Blocked traffic is dropped.
A firewall can be a box, a program on a computer or a service in the cloud.
The jobs a firewall does
| Job | Example |
|---|---|
| Block unwanted traffic from outside | Stop a stranger reaching the staff file share |
| Allow the traffic the business needs | Let customers reach the web server |
| Limit what leaves the network | Stop a program that is sending data out |
| Keep a record | Write every blocked attempt in a log |
The cells students fill in are left blank in this preview.
Check
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Check
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.