Security of Disk Image Encryption

[Scottyk9]

I was wondering if anyone knows how secure an encrypted disk image is? Can it be hacked? Is the encryption just to mount the disk, or is all the data encrypted as well (as I understand is done with FileVault).

I have files that I sync between computers on a portable hard drive containing info that is confidential (no not that... I am a health care worker!). If I lost that drive, what are the chances that someone could access the data (and get me sent to jail!).

I have not tried FileVault for this as I heard that it has been problematic in earlier versions of OS X. Is this now resolved, and is FileVault better than an encrypted disk image??

Thanks everyone.

 

[bograt69]

As far as i'm aware, filevault basically makes an encripted disk image of your home directory, then deletes the original when you log out.

Making an encripted disk image yourself gives you the option of encripting it using AES-128 encription so they should have similar levels of security.

Mike

 

[jsw]

Sorry - I'd intended to reply days ago but forgot.

You can set up the disk image encryption to be as "tight" as File Vault. In particular, if you are transferring files, you want to use the disk image method, since the File Vault files aren't going to be encrypted at all when you copy them - they are only encrypted while they reside in your home folder.

So, in summary, disk image files are secure, and they are in most ways better than using File Vault. You can find specific instructions from me a few posts down in this thread.

 

[Scottyk9]

Thanks for the replies, much appreciated.

When I didn't get a response initially I searched more on Apple's site, and found a pdf that pretty much confirms this. I wanted to make sure that the files were encrypted (not just a secure password to mount the image), and it appear that is the case.

Thanks again