Flexible automated connection to virtual private networks

A network interface unit is provided for use intermediate a LAN and a public or private network, or a combination of both, for establishing secure links to a VPN gateway. Login by a LAN client with the network interface unit, addressing, authentication, and other configuration operations achieved using a web page-based GUI are applied in establishing tunnels from LAN clients to desired VPN destinations. Illustrative network interface units include a DHCP server and provide encryption-decryption and encapsulation-decapsulation of data packets for communication with VPN nodes. Configuration and connection of a client are further enhanced by a built-in DNS server and other functional servers to provide a high degree of autonomy in establishing connections to a desired VPN gateway via an ISP or other public and/or private network links to. The interface unit then performs required authentication exchanges, and required encryption key exchanges.