Originally Posted by Hellmark
The thing is though, the key could be anything. OpenPGP is completely opensource, and operates on roughly the same principles as DRM, and is considered one of the most secure encryption methods available to the public. You don't hear about that getting cracked. It is not as simple as "the key must be stored here, so copy that and you're freely available to open it". And hell, even if you go based on your methods, that isn't any more secure than Adobe ADEPT or any of that stuff.
It is exactly as simple as "the key must be stored here, so copy that and you're freely available to open it".
Open Source software means the source code is available. So you can easily tell exactly how the key is stored or generated, and what algorithm is used to decode.
OpenPGP is secure (colloquially) because people keep their keys secret. A DRM system can't keep the keys secret. The end users's software must have the key for the end user to be able to read the book.