One method used by distributed networks to provide fail-over to a branch office was an inexpensive DSL link allowing for a VPN connection should the primary WAN connection get lost. The problem with that method is that it is rarely tested and takes time to establish a VPN in the event of an outage. SD WAN technology now allows for 2 simultaneous connections such as MPLS and a broadband circuit which fixes the instant fail-over issue but SD WAN adds some expense to the equation and still depends on the cable in the ground to survive a cut.
The least expensive way to create a true redundant network connection that will instantly fail-over is 4G LTE. An LTE Fail-over appliance provides a secondary WAN or Internet connection over the 4G mobile broadband. This wireless link does not rely on last-mile wired connectivity, as MPLS infrastructure or fiber does. When the main wired link fails, the traffic is automatically redirected to the wireless connection, restoring network access. A 10mb private connection including the appliance runs less than $75 per month or the equivalent of a cable or DSL circuit. Soon 5G will be available in more and more markets and the use of wireless data connectivity will be even more prominent.
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