What is VPN?
- Provide privacy by hiding your internet activity from your ISP (and government)
- Allow you to evade censorship (by school, work, your ISP, or government)
- Allow you to “geo-spoof” your location in order to access services unfairly denied to you based on your geographical location (or when you are on holiday)
- Protect you against hackers when using a public WiFi hotspot
- Allow you to P2P download in safety.
Note that using a VPN service does not replace the need for an Internet Service Provider, as it is your ISP that provides your internet connection in the first place.
How does it work?
Normally, when you connect to the internet you first connect to your Internet Service Provider (ISP), which then connects you to any websites (or other internet resources) that you wish to visit. All your internet traffic passes through your ISP’s servers, and can be viewed by your ISP.
When using VPN you connect to a server run by your VPN provider (a “VPN server”) via an encrypted connection (sometimes referred to as a “VPN tunnel”). This means that all data traveling between your computer and the VPN server is encrypted so that only you and the VPN server can “see” it. This setup has a number of important consequences:
Your ISP cannot know what you get up to on the internet
Your ISP can only see that you are connected to the VPN server.
- It cannot see your data because it is encrypted
- It cannot know which websites (etc.) you visit because all internet activity is routed through the VPN server. Your ISP can only see that you are connected to the VPN server.
You appear to access the internet from the IP address of the VPN server
- If the VPN server is located in a different country to you, then as far as the internet is concerned you are located in that country (most VPN services run servers located in many different countries).
- Anyone monitoring your internet activity from the internet will only be able to trace it back to the VPN server, so unless the VPN provider hands over your details (more on this later), your real IP address is hidden. This means that websites etc. cannot see your true IP address (just that of the server).
It is safe to use public WiFi hotspotsbecause the internet connection between your device and the VPN server is encrypted. Even if a hacker somehow manages to intercept your data, for example by tricking you into connecting to an “evil twin” hotspot or packet-sniffing your WiFi data, the data is safe because it is encrypted.
Your internet may slow down because:
- Encrypting and decrypting data requires processing power. This also means that, technically, the stronger the encryption used, the slower your internet access. However, given the power of modern computers, this issue is relatively minor compared to…
- The extra distance traveled by your data. Using VPN always introduces another leg to the journey that your data has to travel (i.e. to the VPN server), and thanks to the laws of physics, the further your data has to travel, the longer it takes.
If you connect to VPN server located geographically nearby in order to access a website also located nearby, then you can expect around a 10 percent hit to the internet speed you get without using VPN. If you connect to a server half way across the planet, you should expect a much greater hit.
All other things being equal, for best performance when using VPN you should connect to the VPN server closest to the website or service you wish to use, and then as close as possible to your own location.
For example, if I want to access US Netflix from the UK I would connect to a server located in the US, but as close as possible to the UK (somewhere on the northern East Coast, such a New York, would be ideal).