speadstream is not a valid model number. Neither is Speedstream. Speedstream model numbers are like 6520, 4100, and 5890. Please provide a valid model number if you expect anyone to help you.
This is the manufacturers driver page: http://ts.fujitsu.com/support/downloads.html
supposedly, as shown in the USA support page from this web page: http://www.usa.siemens.com/entry/en/...-510905-510905
Connect it via the ethernet port (as it was intended) and you don't need a driver. I'm unsure if a usb driver even exists. If a usb driver does exist, then it should have come on a cd disk included with the device or possibly from the ISP.