What is a VPN?
Why Interviewers Ask This
Foundational questions like this help interviewers calibrate the rest of the interview. A confident, accurate answer signals that you have solid Networking basics — a prerequisite for any developer role.
Answer
A VPN (Virtual Private Network) creates an encrypted tunnel between your device and a remote server over the public Internet, making your traffic private and secure. It serves two main purposes. Remote access VPN: allows employees to securely connect to a company's internal network from home or while traveling — their device joins the corporate network as if physically present. Site-to-site VPN: connects two or more office networks securely over the Internet, replacing expensive dedicated leased lines. Consumer VPNs mask your real IP address and encrypt your Internet traffic from your ISP. VPN protocols: OpenVPN (open-source, very secure), WireGuard (modern, fast), IPsec/IKEv2 (used by many enterprise VPNs), L2TP/IPsec. VPNs do not make you completely anonymous — the VPN provider can see your traffic.
Pro Tip
This topic has Networking-specific nuances that differ from general programming. Highlighting those nuances in your answer shows expertise rather than generic knowledge.
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