The Basics of Computer File Shredding

Overview ================ Nowadays, privacy is a big concern. With the whole world moving onto social networks, there will be instances when you end up sharing more information than you initially intended to. In addition to locking down your social media profiles, you should also ensure that the files on your computer are just as secure with the use of file shredding software. Most people are already aware that when you delete a file it is not immediately deleted permanently. It is first moved to a special ‘holding area’, known as the ‘Recycle Bin’ in Windows. Users must manually issue the order to delete the file for good. The purpose of this feature is to allow you to recover a file you may have accidentally deleted. However, with modern software and some relatively simple techniques it may still be possible to recover a file that has been deleted, even from the holding area. Technological Overview ================ To understand how this is possible, it is first necessary to understand how a hard drive manages files. In the simplest terms possible, files are represented as a series of blocks on a hard drive. These blocks are laid out, one after another in sort of a ‘straight line’. Each group of blocks is placed next to another group, and so on. The important thing to note about these blocks is that they are marked as ‘locked’ by your system, and nothing can touch them. Now, when you permanently delete a file from a hard drive, the file isn't erased completely. What the drive does is mark the space that is occupied by your file and allows software, like the operating system, to write over it. It is then possible to recover a deleted file, but only if the space it occupied on the hard drive has not been overwritten. This is how forensic experts recover evidence in criminal cases. Information can also be exploited by malicious hackers and thieves. How the Software Works ================ File shredding software is designed to make your deleted data unrecoverable. It works by taking each block marked as free space by your computer and filling it with random, meaningless data. Some programs choose to write random letters, numbers, or symbols, whereas others alternate between 0's and 1's. Either way, once the program is done, any data that was deleted would be lost for good. Although you may be tempted to run the software multiple times to “ensure” that your data is erased, it does not appear to make any difference at all. According to a study published by the National Institute of Standards and Technology (NIST), on almost all modern drives, one erasure is enough to ensure that none of the data can be recovered. Subsequent erasures give no additional erasure. Software Solutions ================ There are a number of different software solutions available, for both regular home users and corporate users. First is Darik's Boot and Nuke, also known as DBAN. This file shredder is designed to boot from removable storage like a USB flash drive, CD-ROM, or DVD-ROM and works by filling up empty blocks of space with random numbers. Second, is a program called HDDErase. This program is unique for two reasons. First, it was recommended by the National Institute of Science and Technology as a disk purging method in one of their publications. Next, as opposed to DBAN, which focuses on rewriting blocks of free space, HDDErase works by accessing the hard drive's internal firmware and using its built-in mechanisms for erasing data on the hard drive. Last, but not least, is BCWipe, a commercial, military-grade data erasure solution. Whereas the other two entries on this list were open-source and freeware, BCWipe is a proprietary solution developed by Jetico Incorporated. It has been trusted and approved by the U.S. Department of Defense for use in clearing up data spills and removing untrusted data from government computers. It is also used by national laboratories, universities, the military, and numerous government agencies. It has the most features of the three and can accommodate a number of different wiping schemes. Conclusion =============== It's not unwise to want to keep your secrets safe from prying eyes and these tools will help you do it. File shredding software is sure to become more popular as the digital age advances.

Jennifer is a business consultant and has worked with different companies in her career. She thinks that it is important for businesses to dispose of private documents through shredding services to protect information. For more details, please visit The Shredding Alliance.