The same basic idea as DoD 5220.22-M, but with only a single verification step. RCMP TSSIT OPS-II: Overwrite the data with zeroes, ones, zeroes, ones, zeroes, ones, and random data, and verify the final write. The problem with this is that the on-disk encoding is not simple binary data the encodings of a value and its inverse may not themselves be inverses. The first two wipes theoretically pull the magnetic field fully one direction, then fully the other, eliminating any residue of the original value. A three-letter agency may be able to recover data from a zero-wiped drive, but if your opposition is a three-letter agency, you really should be looking into physical destruction instead.ĭoD 5220.22-M seven-pass: I haven't been able to find a description of this, but I suspect it's a variation of the three-pass wipe, only with three values and their inverses.ĭoD 5220.22-M three-pass: Overwrite the data with a value, then with the inverse of that value, then with a random value, verifying the write after each step. For modern hard drives, the main difference is how long it takes - the quality of the wipe is effectively constant between them.

Dod wipe