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(1) FileVault can only encrypt a user's home directory or selected disk images; it does not encrypt the operating system partition and is therefore not considered whole disk encryption. Because of this, FileVault is only an acceptable encryption method in the limited situations where SecureDoc (or another whole disk encryption solution) is not feasible (e.g. Boot Camp users).
(2) TrueCrypt can only encrypt the operating system partition on Windows systems; the Mac and Linux versions of TrueCrypt do not support this feature. TrueCrypt, by itself, is only an acceptable encryption method for Mac and Linux in cases where another whole disk encryption product (e.g. SecureDoc, LUKS, etc.) is not feasible. For Mac BootCamp users, TrueCrypt may be used to encrypt the Windows partition.
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