How VPNs Work
A Virtual Private Network (VPN) creates an encrypted tunnel between your device and a VPN server, routing your traffic through that server. This hides your IP address from the destination and protects your data from eavesdropping on untrusted networks — but VPNs are widely misunderstood.
How Tunneling Works
When you connect to a VPN, a secure tunnel is established between your device and the VPN server. All your network traffic is encrypted before leaving your device, travels through the tunnel to the VPN server, and is then decrypted and forwarded to the destination. The destination sees the VPN server's IP address, not yours. Return traffic follows the same path in reverse.
Encryption and Protocols
VPN protocols define how the tunnel is created and secured. The main protocols are:
WireGuard — modern, fast, simple (~4,000 lines of code). Uses state-of-the-art cryptography (ChaCha20, Curve25519). The preferred choice for new deployments.
OpenVPN — mature, battle-tested, highly configurable. Uses TLS for the control channel and can run over TCP or UDP. Widely supported but more complex.
IPsec/IKEv2 — built into most operating systems. Good for mobile devices because it handles network switching (Wi-Fi to cellular) gracefully.
You can use the Hash Generator to verify file integrity when downloading VPN client software.
What a VPN Protects
A VPN protects against eavesdropping on the local network (coffee shop Wi-Fi, hotel networks). It hides your IP address from destination servers. It can bypass geographic restrictions by making your traffic appear to originate from another country. For developers, VPNs provide secure access to private infrastructure without exposing services to the internet. Check your apparent IP address with the IP Lookup tool before and after connecting to verify the VPN is working.
What a VPN Does Not Protect
A VPN does not make you anonymous — the VPN provider can see all your traffic. It does not protect against malware, phishing, or compromised websites. It does not encrypt traffic between the VPN server and the destination (HTTPS does that). And it does not prevent tracking via cookies, browser fingerprinting, or account logins. VPN marketing often overstates the privacy benefits.
Split Tunneling
Split tunneling routes only specific traffic through the VPN while the rest uses the regular internet connection. This is useful when you need VPN access to internal services but do not want to route Netflix or video calls through the VPN (which adds latency). Most VPN clients support split tunneling by IP range, application, or domain.
VPNs for Developers
Developers commonly use VPNs to access private cloud VPCs, staging environments, and internal tools. Site-to-site VPNs connect office networks to cloud environments. WireGuard makes it easy to set up a point-to-point VPN between a laptop and a cloud server in minutes. Use the Base64 Encoder to encode WireGuard configuration files when sharing them securely.
When You Actually Need a VPN
Use a VPN when: working on untrusted networks, accessing private infrastructure remotely, bypassing network restrictions in restrictive environments, or testing geo-specific behaviour. You probably do not need a VPN for general browsing on your home network — HTTPS already encrypts your traffic end-to-end, and DNS-over-HTTPS protects your DNS queries.
Self-Hosted vs Commercial VPNs
Commercial VPNs (Mullvad, Proton VPN) are convenient but require trust. Self-hosted VPNs (WireGuard on a VPS) give you full control but require setup and maintenance. For developer use (accessing private infrastructure), self-hosted or corporate VPNs are standard. For privacy, a reputable commercial provider with a no-logs policy and independent audits is the pragmatic choice.