What Is a VPN and How It Can Help Me? Simply a VPN server is a middle-man device between your internal office network-to-Internet. It protect your browsing communication data via called VPN TUNNEL which like water passing thru a pipe, which is not leaked outside. Effectively, there are few security mechanism involved on VPN servers called SECURITY LAYERS. It consits of data encryption, authentication, End-to-End connection integrity checks, data communication secured with TLS certs, etc.