Network interface device having primary and backup interfaces for automatic dial backup upon loss of a primary connection and method of using same

摘要

A network interface device to connect a network to a virtual private network comprises a primary interface to a public network, such as an Ethernet interface to a WAN or the Internet, and a secondary, back-up interface to the public network. The secondary back-up connection is activated automatically when the primary connection fails. The network interface device may be provided with further functionality that enables secure communication over both the primary and secondary connection