Destruction and Disposal Methods
Think of all the sensitive data written to a hard drive. Said drive can contain information about students, about clients, about users, about anyone and anything. That hard drive can be in a desktop PC, in a laptop, or even in a printer (many laser printers above consumer grade offer the ability to add a hard drive to store print jobs), and if it falls into the wrong hands, you can not only lose valuable data but also risk a lawsuit for not properly protecting privacy. An appropriate data destruction/disposal plan should be in place to avoid any potential problems.
Since data on media holds great value and liability, that media should never be simply tossed away for prying eyes to stumble upon. For the purpose of this objective, the media in question is hard drives, and there are three key concepts to understand in regard to them: formatting, sanitation, and destruction. Formatting prepares the drive to hold new information (which can include copying over data already there). Sanitation involves wiping the data on the drive off of it, while destruction renders the drive no longer usable.
Low-Level Format vs. Standard Format
There are multiple levels of formatting that can be done on a drive. A standard format, accomplished using the operating system’s FORMAT utility (or similar), can mark space occupied by files as available for new files without truly deleting what was there. Such erasing—if you want to call it that—doesn’t guarantee that the information isn’t still on the disk and recoverable.
A low-level format (typically only accomplished in the factory) can be performed on the system, or a utility can be used to completely wipe the disk clean. This process helps ensure that information doesn’t fall into the wrong hands.
A low-level format is performed on integrated device electronics (IDE) hard drives by the manufacturer. Low-level formatting must be performed even before a drive can be partitioned. In low-level formatting, the drive controller chip and the drive meet for the very first time and learn to work together. Because IDE drives have their controllers integrated into the drive, low-level formatting is a factory process with these drives. Low-level formatting is not operating system dependent.
The main thing to remember for the exams is that most forms of formatting included with the operating system do not actually completely erase the data. Formatting the drive and then disposing of it has caused many companies problems when the data has been retrieved by individuals who never should have seen it using applications that are commercially available.
Hard Drive Sanitation and Sanitation Methods
A number of vendors offer hard drives with Advanced Encryption Standard (AES) cryptography built in, but it’s still better to keep these secure hard drives completely out of the hands of others than to trust their internal security mechanisms once their usable life span has passed for the client. Some vendors include utilities to erase the hard drive, and if it is a Serial ATA (SATA) drive, you can always run HDDERASE, but you are still taking your chances.
In addition to HDDERASE, you can find a number of other software “shredders” by doing a quick Web search. It is important to recognize and acknowledge that many of these do not meet military or GSA specifications, and those specifications should be considered as guidelines that you also adhere to when dealing with your own, or a client’s, data. The only surefire method of rendering the hard drive contents completely eradicated is physical destruction.
Overwrite
Overwriting the drive entails copying over the data with new data. A common practice is to replace the data with 0s. A number of applications allow you to recover what was there prior to the last write operation, and for that reason, most overwrite software will write the same sequence and save it multiple times.
Drive Wipe
If it’s possible to verify beyond a reasonable doubt that a piece of hardware that’s no longer being used doesn’t contain any data of a sensitive or proprietary nature, then that hardware can be recycled (sold to employees, sold to a third party, donated to a school, and so on). That level of assurance can come from wiping a hard drive or using specialized utilities.
If you can’t be assured that the hardware in question doesn’t contain important data, then the hardware should be destroyed. You cannot, and should not, take a risk that the data your company depends on could fall into the wrong hands.
Physical Destruction
Physically destroying the drive involves rendering the component no longer usable. While the focus is on hard drives, you can also physically destroy other forms of media, such as flash drives and CD/DVDs.
Shredder
Many commercial paper shredders include the ability to destroy DVDs and CDs. Paper shredders, however, are not able to handle hard drives, and you need a shredder created for just such a purpose: Jackhammer makes a low-volume unit that will destroy eight drives a minute and carries a suggested list price of just under $30,000.
Drill
If you don’t have the budget for a hard drive shredder, you can accomplish similar results in a much more time-consuming way with a power drill. The goal is to physically destroy the platters in the drive. Start the process by removing the cover from the drive—this is normally done with a Torx driver (while #8 does not work with all, it is a good one to try first). You can remove the arm with a slotted screwdriver and then the cover over the platters using a Torx driver. Don’t worry about damaging or scratching anything—nothing is intended to be saved. Everything but the platters can be tossed away.
As an optional step, you can completely remove the tracks using a belt sander, grinder, or palm sander. The goal is to turn the shiny surface into fine powder. Again, this step is optional, but it adds one more layer of assurance that nothing usable remains. Always wear eye protection and be careful not to breathe in any fine particles that you generate during the grinding/destruction process.
Following this, use the power drill to create as small a set of particles as possible. A drill press works much better for this task than trying to hold the drive and drill it with a handheld model.
Electromagnet
A large electromagnet can be used to destroy any magnetic media, such as a hard drive or backup tape set. The most common of these is the degaussing tool, discussed next.
Degaussing Tool
Degaussing involves applying a strong magnetic field to initialize the media (this is also referred to as disk wiping). This process helps ensure that information doesn’t fall into the wrong hands.
Degaussing involves using a specifically designed electromagnet to eliminate all data on the drive, and that destruction also includes the factory prerecorded servo tracks. You can find wand model degaussers priced at just over $500 or desktop units that sell for up to $30,000.