How does a VPN work?
The tunnel, the server and the encryption explained step by step.
By VPNGuide Editorial Team · Updated 20 September 2026
Your device runs a VPN application that authenticates with a server and negotiates encryption keys. From that point, traffic is encapsulated inside an encrypted tunnel using a protocol such as WireGuard or OpenVPN.\n\nThe VPN server decrypts the traffic and forwards it to the wider internet, then returns responses through the same tunnel. Because the decryption happens on the provider's hardware, infrastructure decisions such as RAM-only servers are meaningful.
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