said by »support.apple.com/en-us/HT202064 :Data protection enhances the built-in hardware encryption by protecting the hardware encryption keys with your passcode. This provides an additional layer of protection for your email messages attachments, and third-party applications.
From your own link. Everything stored on the phone is encrypted by default, however without the passcode it's encrypted with the standard hardware key. That key can be extracted by attackers, therefore it is not considered "protected" even though it's encrypted. If you add a passcode, data is encrypted with both the hardware and passcode keys, making it more difficult/impossible to decrypt.
The Erase iPhone button (what we're discussing in this thread) works the same way whether or not you have a passcode set.
Edit: I just want to add, before somebody jumps all over me, that I'm purposefully being a bit vague/loose with how these mechanisms actually work, because it's not all that important. Apple wrote a really great and incredibly easy to understand white paper on the whole system: »
www.apple.com/br/privacy ··· 2014.pdfDevice encryption starts at page 9 if you want to learn how everything actually works, but the figure on page 10 sums it up quite nicely. Here's the relevant parts:
quote:
The metadata of all files in the file system is encrypted with a random key, which is created when iOS is first installed or when the device is wiped by a user. ... Since its stored on the device, this key is not used to maintain the confidentiality of data; instead, its designed to be quickly erased on demand (by the user, with the Erase all content and settings option, or by a user or administrator ... Erasing the key in this manner renders all files cryptographically inaccessible.
The content of a file is encrypted with a per-file key ... which is in turn encrypted with the file system key. The class key is protected with the hardware UID and, for some classes, the users passcode.
So all data is encrypted by default. If you have a passcode, certain classes of files are encrypted with a combination of the hardware and passcode key. If you don't have a passcode, it's encrypted just with the hardware key.
tl;dr: The "Erase iPhone" button will simply erase the keys that encrypt every user-generated file on your phone. This works regardless of your passcode settings.