Wiping
Secure Wiping / Data Erasure
Sicheres Löschen von Daten
Wiping denotes the secure, permanent deletion of data through actual overwriting — in contrast to normal „deleting“, which usually only removes the reference while the contents remain. The aim is that the data can no longer be reconstructed even by forensic means. It is the other side of forensics: the deliberate destruction of traces.
History & facts. Those who „delete“ a file usually only remove the reference in the file system; the content remains physically present and is reconstructable with methods such as file carving. Secure deletion overwrites the occupied area with defined patterns. On magnetic hard disks, a single overwrite is today usually considered sufficient; SSDs require, because of their internal storage management, different, vendor-side methods. A particularly thorough variant is the physical destruction of the data carrier.
Outlook & recommendation. Secure deletion is relevant for the decommissioning of devices, data protection (erasure duties) and the clean separation of legacy data. For the defence this entails two things: on the one hand it is mandatory when disposing of devices, on the other hand its abusive use by attackers is an anti-forensic signal. What matters is to choose a method suited to the medium and to verify success — an unverified deletion is not a secure deletion.