A private road through a public town
A worker at a coffee shop needs the office file share. The coffee shop Wi-Fi is open to everybody.
Sending work files across it is like carrying cash through a crowd. A VPN is a private, covered tunnel through the same crowd.
Today you choose and apply one.
Key words
| Word | What it means |
|---|---|
| VPN | Virtual private network: an encrypted tunnel across a public network, so it acts like a private one. |
| Tunnel | A protected path that carries traffic inside other traffic. |
| Intranet | The private web pages and services that only staff can reach. |
| IPSec | A set of rules that protects each IP packet: it can check it and lock it. |
| ESP | The IPSec part that locks (encrypts) the packets. |
| AH | The IPSec part that proves packets were not changed. It does not lock them. |
| IKE | The IPSec step where two ends agree their keys. |
| Packet | A small chunk of data sent across a network. |
| Network | Computers and devices linked so they can share data. |
| Encryption | Scrambling data so only a person with the right key can read it. |
| Malware | Software made to harm a computer or steal data. |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can explain what a VPN is for, tell remote access from site-to-site, and say what IPSec adds.
Starter: separating traffic
Have a go
Starter: separating traffic
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Cycle 1: what a VPN does
A VPN builds an encrypted tunnel across a public network such as the internet. Traffic inside is hidden from everyone on the way. The worker's laptop acts as if it is plugged in at the office.
It reaches things only staff should reach: the intranet, file systems and other local network systems.
Two kinds of VPN
| Kind | What it joins | Example |
|---|---|---|
| Remote access | One user to the office | A worker at home opens the file share |
| Site-to-site | Two whole networks | Head office and a warehouse share files all day |
The cells students fill in are left blank in this preview.
Check: which VPN?
Have a go
Check: which VPN?
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.