Securely”‹ Extend the Life of a Storage Device: Data Destruction / DoD Wipe

By Jeff Krueger, Director of Engineering, Dedicated Computing

Data can be removed from a storage device using various methods, each with various security implications. 

For starters, metadata can be changed on the drive indicating that parts of it are now empty; no data was overwritten and can still be recovered.

Secondly, the data on the drive can be overwritten; in this case it may still be possible to recover the data that was previously there. Subsequent overwriting passes make data recovery more difficult.

Finally, the drive can be destroyed, rendering it and the data on it unusable.

In order to continue to use drives securely for multiple purposes throughout their lives, the DoD sets standards for secure data destruction. DoD 5220.22-M involves a three-write pass. On the first, zeros are written over the data to be destroyed. On the second pass, ones are written. On the third, random characters are written. DoD 5220.22-M ECE is a seven-write pass for added security. It’s passes include 0’s, 1’s, random characters, random characters, 0’s, 1’s, and random characters.

Securely”‹ Extend the Life of a Storage Device: Data Destruction / DoD Wipe