Solid State Drives Are Fast, Reliable, and Very Difficult to Securely Erase

Solid State Drives (SSD) use solid-state memory instead of spinning disc platters (as in hard disk drives) to store large ammounts of data. SSD prices have been dropping while storage capacities have been increasing in the past few years. SSDs can provide greater realiability and access speed at a higher cost per byte. Perhaps the best known SSD device is Apple’s MacBook Air.

Price is not the only cost involved, however. Security firm Sophos reports that:

SSDs prove difficult to securely erase

They note that ATA and SCSI disk driver controllers’ erase unit feature for secure erasure was only available on 8 of 12 SSD drives tested and worked only on 4 of the 8 supported disks. The degaussing process used for hard drives, which are based on magnetic storage, does not work on SSDs. And, conventional file destruction methods do not work.

Sophos recommends full disk encryption as the only practical form of data protection for SSDs.