Copy protection and the linux dd command

[xonto]

Alright. I understand the basics of copy protection. That is to say, I have been working with computers for 10+ years and have read several wikipedia pages on the topic.

My question is: Why does, more often than not, a standard bit-stream copy of dvd fail? What happens when you make what should be an exact copy of a disk that makes the disk not work in place of the original, and how does software that beats copy protection do it? Ultimately, why/how does the linux dd command fail at producing perfect copies of any media?

 

[Styrak]

I believe talking about breaking copy protection is highly frowned upon in these forums, and is prohibited.

 

[xonto]

Description for the forum is: "CD/DVD Players/Burners/Media and duplication software/techniques."

I am not asking about how to break copy protection. I am simply asking a question about what copy protection is and how it works; simply a question about duplication.

I am asking about the technology behind copy protection (as it relates to duplication) because I am genuinely curious about how it works. This is not about me wanting to get tips on how to break the copy protection; I know how to break copy protection already, if I want to. I mean, you do not need to understand it to download a program that can do it. I really just want to know why methods like the Linux dd command (or any bit-stream copier or exact duplication/imaging software) do not work, and why you need special programs that will strip it out.

I understand if you don't want to talk about it, but honestly, if you post something that actually will help me or anyone else break copy protection, then you're posting the wrong info. (Unless someone uses the information you post to write their own full-featured, copy protection removing software. And if the person is a good enough coder to do that, then they probably already know anything that you would post on the topic.)