On Dec 5, 2007 4:05 PM, <[EMAIL PROTECTED]> wrote: > ... Have you actually tested using a magnetic field for this ...
despite the rudeness of some of this thread, it really is difficult to properly clear / purge data from a modern hard disk using a magnetic field. we do this at work, and the device is a large box with loud fans. you must wear heat resistant glove(s) to hold the hard drive over the unit for 60+ seconds. it gets quite hot (see inductive smelting, etc). arranging such a unit inside a case would be difficult, dangerous, and probably not as effective as you think. see http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html this is why full disk encryption is preferable. it is much quicker and safer to securely purge or destroy the disk keys (small) than the whole disk itself (large, time consuming). there are many ways to configure authentication/authorization for encrypted disk access, including multi-factor passphrase, token, even biometric. maybe you leave the keys on disk for headless boot and only want the ability to securely wipe them if needed. last note, the loop-aes module support key scrubbing in memory, so that even ram cannot be inspected for usable disk encryption keys that could remain after power down. (some other volume encryption methods may also support this, however, loop-aes is the only one i've used that does so.) best regards,