"One of the great advantages of eCryptfs is that the encryption is made at the single-file level and all the metadata needed for encryption/decryption are embedded in the file itself. This process makes each file a little larger than the decrypted version, but it enables:
"* Having under the same directory files encrypted by different users and with different encryption contexts, and each user can access only his/her files;
* Moving individual files by copying them in encrypted form to another location where they will be accessible simply by using the right encryption context;
* Using backup tools that allow incremental file transfer."
