Sanitizing Electronic Information

Hard Drive (1)

Most of the information/data sanitization methods, support structures and commercial solutions currently available to destroy stored electronic information differ widely in terms of the media types and information formats that they support. Hence, some information sanitization methods/solutions perform better at certain specific tasks when operating on specific media types, than is the case when they are operating on other information sanitization task/media combinations.

The following list describes the major mechanisms currently used to ensure adequate destruction (sanitization) of the information contained within information storage systems. Should you need to destroy any stored information, information storage media, information storage device(s) or information storage systems then it is most advisable that you employ two or more of the methods listed below. Your sanitization process options are:

Physical Destruction

When it comes to the physical destruction of an electronic information storage device the basic process involves electrically and magnetically sanitizing the device followed by physical destruction of the device using such tools as a sledgehammer or a blowtorch. The entire physical destruction process is:

1. Overwrite the media three times using a randomized pattern of ones and zeros
2. Degauss the media
3. Overwrite the media three times using real but irrelevant data such as MP3s, WAV files, PDF documents, word documents, text files, jpeg files, mpeg files etc
4. Degauss the media
5. Overwrite the media three times using a randomized pattern of ones and zeros
6. Degauss the media
7. Physically destroy media/device using sledgehammer etc

Degaussing:

Usage Indicators – Most magnetic and electronic storage media, including hard drives are suitable for degaussing

Best Single Use Method – Degaussing is probably your best and fastest single option in circumstances where you can be sure of the storage media/device’s history and you intend to reuse that device or storage medium

Degaussing (2)

Device/Media Life Expectancy – Whenever device or media life expectancy is a weighty factor, degaussing is once again your best option. Since degaussing is a magnetic procedure, it requires no moving parts and can therefore prolong the working life of storage media and devices especially in comparison to device/media sanitization by erasure using overwriting processes that do involve mechanical processes such as spinning hard drive platters or tape reels. These mechanically driven storage devices/media do by their very nature cause wear and tear.

Speed – Degaussing is by far the fastest of the sanitization options listed here because it affects all sectors of the storage medium/device simultaneously whereas sanitize by overwrite procedures are limited to the maximum write speed of the media/device being sanitized.

Sanitizing USB Flash Drives – There is an upper limit to how many times a USB flash drive can be overwritten before it fails permanently. Since degaussing is a magnetic procedure and does not require an overwriting process using it to clear or reset a USB flash drive will greatly extend said USB flash drive’s usable life expectancy.

Low-Level Formatting

A basic low-level format is not of itself sufficient to meet the most basic of information sanitization requirements. In fact, even a multi-pass low-level format strategy no longer satisfies the generally accepted minimum requirements for information sanitization.

Therefore, whenever the output of your information sanitization procedure is to leave your physical control you must implement additional information sanitization procedures. For instance, the physical destruction of the media/device immediately or very soon after the low-level formatting passes have been made. A number of passes using randomized patterns of ones and zeros will also be required.

Low-Level Hard Drive Formatting (3)

if you intend to reuse the information storage medium/device then a three pass low level formatting sanitization strategy may be sufficient. It is your assets and your decision. You will however, need to ensure that your formatting tool is of highly reliable quality.

All low-level formatting regimes need augmenting with additional procedures such as multi-pass regimes consisting of randomized ones and zeros, real world non-related data (MP3s, photos etc), degaussing and physical destruction.

Consider using a full disc low-level butterfly format pass as it is much more effective than the standard formatting processes. It does however take considerably longer to perform.

Overwriting

Overwriting or wiping as it is also known is only reliable when used in combination with other techniques such as degaussing. By itself, it is probably the least reliable of all of the methods discussed here. The reason for this is that a thorough and methodical approach in conducting a three-pass overwrite cycle is essential. This is something that the Department of Defense can ensure through military discipline.

Repeatedly performing this procedure numerous times, a day is not something to look forward to with any great anticipation. Human nature being as it is shortcuts and slackness will rapidly become the norm. It is also a lengthy process and hence not cost-effective.

Solid-State Drive (4)

Specialty Information Sanitization Solutions:

There are a number of hardware-based and software-based information sanitization solutions available each with its own merits and drawbacks.

In addition, there are also a number of specialist software-only solutions built specifically to address the specific requirements and idiosyncrasies peculiar to the needs of electronic information storage sanitization. Their biggest advantage is that they bring varying degrees of automation to the sanitization party.

The savings made in terms of the reduction in required human input and attendance can be very considerable indeed. Information systems that routinely gather, administer, manage and eventually need to dispose of large volumes of information will benefit greatly from automated data sanitization software.

Conclusion

Although there are a number of ways by which electronically stored information can be irretrievably destroyed or at the very least rendered unrecoverable/unusable not all of these methods are equal in terms of their reliability, thoroughness, cost effectiveness or “user friendliness”.

In general, the decisions concerning which information sanitization tools/methods to employ in any specific information sanitization instance require evaluation on a case-by-case basis. It must also be noted that regardless of the specifics of an information sanitization instance it is always most advisable to never rely upon just one method to get the job done. Use a multi-method approach.