We have purchased and tested this USB to WiFi/Ethernet adapter from Amazon and it works well:http://www.amazon.com/IOGEAR-Wireless-S
IOGEAR Wireless 4-Port USB Sharing Station GUWIP204 (Black)
This device converts USB to Ethernet. This has multiple advantages:
1) You can use much longer wiring or even control the laser from a different room
2) Some users have experience USB disconnects. We attributed many of these problems to flakey USB chipsets on the end user's computer. When they used a newer computer the problem went away. Using this device you should not have any USB disconnects because RetinaEngrave USB will operate over Ethernet and the USB port is not plugged into the computer. The USB connection is only between the GUWIP204 and RetinaEngrave which we have already qualified.
3) You don't need to plug and unplug your computer from the laser itself minimizing the likelyhood of the USB port wearing out.
4) Ethernet is a much more reliable connection over distance/noise.
We strongly recommend you use the wired Ethernet connection instead of the WiFi connection. You can plug an Ethernet cable directly from the USB port on the GUWIP204 to your computer (no router needed). In theory you can operate this over WiFi but wifi is also prone to errors so do so at your own risk.
The recommended configuration is:
RetinaEngrave USB -> plug USB into GUWIP204 -> plug one end of ethernet cable into GUWIP204 and one end into your computer's ethernet jack
Install the RetinaEngrave including USB drivers as normal. In addition install the GUWIP204 software.