How publishers protect e-learning/ educational CD from piracy and how much does the solution cost?

It's called DRM or copy protection, search for vendors of those and you'll find plenty of solutions. They're a waste of time in my opinion, all are cracked eventually and you'll put your paying customers at inconvenience. If I buy your CD I don't want the hassle of having to get a new key down the track (if you're still in business) because I've upgraded PCs 3 times or need to get a replacement CD if I happen to lose it.