A Virtual Private Network creates an encrypted tunnel between a user (or another network) and a private network, enabling remote access as though the user were physically on the private network. VPNs have historically been the default remote-access security mechanism for enterprises, implemented via protocols including IPsec, OpenVPN, and WireGuard.
The enterprise VPN model has been losing ground to zero-trust network architectures in the 2020s. The traditional VPN assumption — "inside the network is trusted, outside is untrusted" — does not hold when attackers can compromise credentials and move laterally, or when employees access resources from unmanaged devices. Zero-trust approaches (Google BeyondCorp, Cloudflare Access, Zscaler) authenticate every request individually rather than relying on network perimeter.
Consumer VPNs — NordVPN, ExpressVPN, Mullvad — are a separate product category that uses the same underlying technology for different purposes (privacy, geo-routing, ISP circumvention). Enterprise and consumer VPN markets have almost no overlap in product positioning despite sharing terminology.