One of the requirements of my web application is for the users to have, in their possession, a CD-ROM that they've purchased. I'm trying to come up with a means to let the web server know that the CD is, in fact, in the CDRom drive and will therefore allow them to continue using the web-based application.

Is there an easy way to do this? Whenever I start brainstorming this, it becomes obvious to me that using a CD as part of a security measure is flawed in that nothing really prevents users from "borrowing" each other's CD.

Anyone care to lend some brainstorming power to my dilemma to help formulate an idea for how to include the CD-Rom drive as part of web-based security?