Take the 2-minute tour ×
Ask Different is a question and answer site for power users of Apple hardware and software. It's 100% free, no registration required.

I have found countless blogs and tutorials how to encrypt an external drive using Mac's extended journaled encrypted format, but I couldn't find anybody stating the standard behind it. I know that FireVault 2 uses XTS-AES 128 encryption, but is that the same used for the external format or are the hard/flash drives simply assigned with a mounting password? Any link for clarification or simply a statement would be very appreciated.

share|improve this question
    
Cannot speak with authority, but FileVault2 is built on top of that new hard disk encryption feature, so this is also almost certainly the same algorithm (at least by default, maybe there are other options). –  Thilo Apr 18 '12 at 9:45
add comment

1 Answer 1

  1. Open Terminal (located in /Applications/Utilities/Terminal.app) and type:

    disktutil cs list
    
  2. Then look for the entry of your standard drive, e.g.

    Name:                    Macintosh HD
    
  3. Look further down to find out the encryption type:

    Encryption Type:         AES-XTS
    

The latter is what I see when using this command in OS X 10.8.2, so you can assume that AES-XTS stands for the AES-XTS 128-bit encryption used in Mountain Lion.

I expect Lion to use the same encryption model, but I can't verify it because I have no Mac that's running Lion. However, the diskutil command should help you to find the definite answer.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.