The Basics of VPN
A VPN (Virtual Private Network) is a technology that creates a virtual, dedicated connection over the internet. When you use a VPN, an encrypted tunnel is established between your device and the VPN server, shielding your communications from third parties.
When you connect to the internet through a VPN, websites see the VPN server's IP address instead of yours. In other words, your real IP address and location become invisible to the outside world.
How Does a VPN Work?
Let's walk through the process of establishing a VPN connection step by step.
- Your device requests a connection to the VPN server through the VPN client
- An encrypted tunnel is established between the two
- All subsequent internet traffic is routed through this tunnel
- The VPN server accesses websites on your behalf and returns the results through the encrypted path
This mechanism, known as "tunneling," makes it extremely difficult for even your ISP or network administrator to determine which sites you are visiting.
Key Benefits of Using a VPN
Privacy Protection
By masking your IP address, a VPN makes it harder for websites and online services to pinpoint your actual location. It also provides a degree of defense against profiling by ad trackers and data brokers.
Security on Public Wi-Fi
Public Wi-Fi networks at cafés and airports often lack adequate encryption. A VPN encrypts your traffic even on these networks, significantly reducing the risk of eavesdropping. For more details, see our article on public Wi-Fi risks.
Bypassing Geo-Restrictions
Some web services, particularly streaming platforms, restrict access based on geographic location. Connecting to a VPN server in another country can sometimes circumvent these restrictions.
Avoiding ISP Throttling
Some ISPs intentionally throttle bandwidth for specific services like video streaming. Since a VPN makes your traffic content unreadable to the ISP, it can potentially bypass such throttling.
Major VPN Protocols
Several communication protocols are used in VPNs, each offering a different balance of speed, security, and compatibility.
WireGuard
A relatively new protocol that delivers fast, robust communication based on a streamlined design philosophy. Its small codebase makes security audits straightforward, and many modern VPN services are adopting it.
OpenVPN
A well-established open-source protocol with a long track record. It combines high flexibility with reliability and runs on virtually every platform. Support for both TCP and UDP is another strength.
IKEv2/IPsec
Highly compatible with mobile environments, this protocol handles network transitions — such as switching from Wi-Fi to cellular — with ease. It offers an excellent balance of speed and security.
How to Choose a Trustworthy VPN Service
Here are the key factors to consider when selecting a VPN service.
- No-log policy: Does the provider explicitly commit to storing no connection logs?
- Third-party audits: Has the service undergone independent security verification?
- Server locations: Are servers available in the countries you need?
- Speed: Is the connection fast enough for everyday use?
- Simultaneous connections: Can you use the service on multiple devices at once?
- Kill switch: Does the client automatically block traffic if the VPN connection drops?
- DNS leak protection: Is there a built-in mechanism to prevent DNS leaks?
For more on DNS leaks, see our DNS leak guide, which also explains how to test for leaks using the Kakunin-san DNS leak test.
Understanding the Limitations of VPNs
A VPN is a powerful privacy tool, but it is not a silver bullet. Keep the following caveats in mind:
- Your activity on services where you are logged in can still be tracked, even with a VPN
- Some free VPNs collect and sell user data
- Your IP address can leak via WebRTC even while connected to a VPN
- Tracking via browser fingerprinting cannot be prevented by a VPN alone
For comprehensive privacy protection, it is essential to combine a VPN with other countermeasures.