Most large software releases – operating systems, office suites and anything else big enough to use an entire CD-ROM disc – are transferred legally (or illegally) in the form of disk images. These are single files (which usually have the extension .ISO, hence “ISO file) that contain the entire contents of the CD or DVD disc with extra “metadata” included – such as the discs’ name and boot information, if required. This allows the end-user to put a blank disc in their drive, open his or her software burning program and click “Burn Image” and end up with a CD full of stuff in just a few minutes. In a nutshell, I can create a CD-ROM named “Pictures” with a variety of digital images on it, create an .ISO file of the disc that I can distribute to anyone, who can then create a million discs just like mine – or send it on to someone else who can then make a million copies of their own.
This is not new. The Linux operating system has been distributed this way for ages. Microsoft rarely mails actual CDs of beta software to testers these days and instead opts to allow users to download ISOs of the beta program – like Windows Server 2008 for example. But what good are the image files aside from allowing users to make flawless copies of CD or DVD discs?
The answer is virtual drives. These programs create one or more “virtual” CD-ROM drives on your PC and allow you to “mount” image files on them as if you were putting a real CD-ROM into a real drive. This not only saves you the hassle of actually burning the discs, it saves money and landfill space in an age when most users have 100+ GB of space on their hard drives. Gamers love virtual drives, as game CD images mounted as virtual drives can have up to 10 times the throughput of an actual CD-ROM drive. Lastly, virtual drives can be used by virtual machine software like Microsoft’s Virtual PC or VMWare’s VMWare Workstation – so I can install a virtual server in a virtual machine using a virtual drive from a disc image – thus never once touching an actual CD-ROM disc!
While virtual CD-ROM drives have been around forever, the adoption of broadband has allowed network transfers of 650+ MB become commonplace. So not only have Linux and Microsoft adopted disk images as a way to distribute software, so too have software and video pirates. You don’t have to worry about getting each and every single file from a DVD or putting the DVD files in the right directory if you have an image file – just click and burn! A while back, only a few folks used virtual drives – now it seems like just about every geek I know uses some form of virtual CD-ROM program.
So – which virtual drive application is right for you? Well, Microsoft offers a free one and the ever-popular Daemon Tools is also free. One of the most popular commercial packages is Alcohol 120% – look for it in Usenet or Bittorrent – or maybe even pay for it! Both Alcohol and Daemon Tools can make “backup copies” (wink, wink) of just about any protected disc on the market – be it SafeDisc or SecureROM or whatever.