Just use the latest StarForce or TAGES protection on the CD's. End users can't make 1:1 backups of them.
Nothing stopping them ripping an image of the disc and downloading a patch, but not everyone knows where to get such patches.
The only other method is a steam-like program that hooks back to a server operated by the place you rented your disc from.
Again, this can (and would be) cracked, just like steam has been.
Nothing stopping them ripping an image of the disc and downloading a patch, but not everyone knows where to get such patches.
The only other method is a steam-like program that hooks back to a server operated by the place you rented your disc from.
Again, this can (and would be) cracked, just like steam has been.