The advanced forensic format (aff) is on-disk format for storing computer forensic information. critical features of aff include:

- aff allows you to store both computer forensic data and associated
metadata in one or more files.
- aff allows files to be digital singed, to provide for
chain-of-custody and long-term file integrity.
- aff allows for forensic disk images to stored encrypted and
decrypted on-the-fly for processing. this allows disk images
containing privacy sensitive material to be stored on the internet.