NIST's Guide to Write Blockers


The National Institute of Standards and Technology's Computer Forensics Tool Testing Program has posted the results of its testing on hardware write blockers. There are separate reports for T4 Forensic SCSI Bridges; Tableau T8 Forensic USB Bridges; WiebeTech Forensic ComboDock; Digital Intelligence Firefly 800 IDE; and FastBlock IDE devices.

Several tests were performed on the write blockers:

1. Identify modifying commands blocked by the Hardware Write Blocker.

2. Attempt to modify a protected drive with forensic tools.

3. Identify read commands allowed by the Hardware Write Blocker [a good result will allow these to be read].

4. Read a protected drive with forensic tools.

5. Identify access significant information unmodified by the Hardware Write Blocker.

6. Determine if an error on the protected drive is returned to the host.