Easiest solution for Ethernet connect to modem

I’m an end user with an application where we are looking to install a modem in a remote location (no PC). I’d rather not install an industrial PC in this location and I’m looking for the easiest way to install the modem and then bridge to Ethernet.

Has anyone successfully used a Xbee 802.15.4 RF modem with a serial to Ethernet bridge? Or alternately has anyone used one of the USB modems with the Digi AnywhereUSB product?

Any other options that would be easy?

Any feedback would be appreciated.