It was provided by MS as a separate package to download for Windows (up to 7).
That class driver allows creating virtual drives on which we can later mount ISOs images.
It's rather basic, but does the job.
To use it, you can use the GUI app from Microsoft (Virtual CD-ROM Control Panel)
or the vcdcli in CLI. We're compatible :-).
Note that it's not loaded at boot, you need to manually start it, to lower memory footprint.
Both applications will handle this for you.
