How do VPNs actually work?

[Norbazol]

im very much a noob here and want to learn, so go easy on me if this is just a silly question.....

everyone hears about vpns and knows they can protect you and allow you to access content.

but how do they actually work? i know it stands for virtual proxy network, but what does a proxy network do and how does it allow your data to be 'protected'. does it encrypt data? if so what kind of encryption do they use? how do companies like nordvpn 'protect your data from hackers', wouldnt someone just have to break into their database and just check what servers a user connected to and where they connected from?

 

[dEEpEst]

Your question is far from silly! Understanding how VPNs work is essential, especially in today's digital landscape. First off, a small correction: VPN stands for "Virtual Private Network," not "Virtual Proxy Network."

A VPN essentially does the following:

1. Encryption: When you use a VPN, your data is encrypted before it leaves your device. This encryption usually involves algorithms like AES-256.
   
2. Data Tunneling: Encrypted data is sent through a "tunnel" to a VPN server.
   
3. IP Masking: The VPN server replaces your original IP address with its own, making it appear as if the data is coming from the server, not from you.
   
4. Decryption: The data is then decrypted and sent to its intended destination. The process is reversed for incoming data.
   

This helps with:

1. Privacy: Your original IP is hidden.
   
2. Security: Encrypted data is hard for eavesdroppers to understand.
   
3. Access: You can bypass geographical restrictions on content.
   

Concerning your question about companies like NordVPN: While it's true that VPN providers could potentially be hacked, reputable services take stringent measures to protect their servers and your data. They also often have a "no-logs" policy, meaning they don't keep records of your online activities.

So, to sum up, a VPN does encrypt your data, masks your IP, and can help protect you from various types of cyber threats.

You may be interested in reading this about VPNs:

 

[Norbazol]

Very informative information, I appreciate the quick response as well.
I now have another question. Regarding eavesdropping in specific, so I've read about wireshark before, is this something a VPN could prevent against? Lets say if someone was on my local network, they ran wireshark and captured packets, would the data from a pc running a VPN be able to be intercepted? i guess what im asking is, really at what stage would the data become encrypted.

 

[dEEpEst]

I'm glad you found the previous information helpful! Wireshark is a network protocol analyzer often used for packet capturing and analysis. If someone were to use Wireshark on your local network and you were not using a VPN, they could potentially see the data packets you're sending and receiving, depending on the encryption level of the sites you're accessing.

If you are using a VPN, however, the data would be encrypted on your device before it even enters the local network. This means that someone using Wireshark would only see encrypted packets traveling from your device to the VPN server. They wouldn't be able to interpret the actual data content.

So, to answer your question about when the data becomes encrypted: The data is encrypted on your device before it gets sent out onto the network. This encryption shields your data from eavesdroppers on your local network.

A very important piece of information is the difference between your request to the server and whether it is http or https: 

When you're using HTTP, the data between your browser and the web server is not encrypted. If someone is eavesdropping on your local network, they could see the content of the HTTP traffic even if you are using a VPN.

However, the VPN still encrypts the data as it leaves your device and heads toward the VPN server. So, the eavesdropper would see encrypted packets going to and from the VPN server, but they wouldn't be able to tell it's HTTP traffic specifically.

In short, a VPN encrypts all your traffic, including HTTP, as it passes through your local network, making it more difficult for local eavesdroppers to decipher the content. But once the data reaches the VPN server and heads to its final destination, if the site you're connecting to is using HTTP, then the data will be unencrypted from that point onward.

The truth is that the world of networks is exciting, I advise you to read about networks. Here in the forum you will find a large amount of information, manuals, courses, tools, etc.