If they are using 'proper' FTDI chips then this should do what you want http://www.ebay.co.uk/itm/USB-to-TTL-Serial-Cable-Adapter-FTDI-Chipset-FT232-Cable-FT232RL-TTL-3-3V-B36-/231609039965?pt=LH_DefaultDomain_3&hash=item35ecf97c5d , just need to wire up an RJ45 on the end... for a little more work in 'potting-up' this may be useful http://www.ebay.co.uk/itm/6PIN-CP2102-USB-2-0-to-UART-TTL-Electronic-Connector-Serial-Converter-Module-/390568169609?hash=item5aefad5089 As for drivers for Windows 8,8.1,10, you need to set the OS into 'allow un-signed drivers' mode (special start-up) which will then install correctly & work ok, I have some on multiple systems