External Overwrite (1-Pass, 3-Pass, n-Pass)
This is the most common form of data sanitization and it's what you'll find in almost any commercial or free application. Indicate the number of overwrites you want and a series of 0's and 1's is written across the drive. More overwrites results in a more thorough data sanitization.
Regardless of the number of passes required for your security needs, the key to a successful overwrite project is auditing and verification. Our team is well versed in auditing large projects of hundred or even thousands of drives, even across multiple sites. We will ensure that you have a thorough accounting of every drive's successful data sanitization for compliance reporting.
Equally important — our team will identify those drives that fail erasure and prepare a secondary compliance log for proper auditing of the degaussing and destruction processes. Not all drives will handle the overwrite process, likely due to physical damage. The ability to monitor the data erasure and identify failures is vital in the ability to ensure all data is properly sanitized and all compliance reporting is valid.
Degaussing
Degaussing is a destructive process, meaning that the drives becomes "bricked" and can no longer operate. Degaussing is a quick and effective method of data eradication if there is no need to re-purpose the HDD assets.
There is some concern that as the linear density of magnetic recording media increases, the resulting increase in magnetic coercivity requires ever stronger magnetic fields for proper degaussing. Simply put – you need to make sure that the degaussing equipment used is not much older than the drives they are to be used on or else you may not be getting the complete data eradication that you wanted!
Physical Destruction
The ultimate destructive process – the physical shredding or incineration of the drives. We strongly recommend that this be performed ONLY after a data eradication option is performed — to ensure that all data is first destroyed and then the physical drive can be safely destroyed.
Even physical destruction is not absolute if any remaining disk pieces are larger than a single 512-byte record block in size, about 1/125" in modern drives. As linear and track densities increases, the maximum allowable size of disk fragments will continue to shrink even further. Destroyed fragments of this size can been imaged and restored using forensic techniques such as magnetic microscopy.