[cryptography] Reliably Erasing Data From Flash-Based Solid State Drives

[Alexander Klimov]

<http://www.usenix.org/events/fast11/tech/full_papers/Wei.pdf>:

  We empirically evaluate the effectiveness of hard
  drive-oriented techniques and of the SSDs' built-in
  sanitization commands by extracting raw data from the SSD's
  flash chips after applying these techniques and commands. Our
  results lead to three conclusions: First, built-in commands
  are effective, but manufacturers sometimes implement them
  incorrectly. Second, overwriting the entire visible address
  space of an SSD twice is usually, but not always, sufficient
  to sanitize the drive. Third, none of the existing hard
  drive-oriented techniques for individual file sanitization are
  effective on SSDs.

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Regards,
ASK