Digital vellum and other cures for bit rot.

• Author: Kosciejew, Marc

In the 20 years since digital preservation expert Jeff Rothenberg sounded the alarm about the danger of losing digital information--and our historical legacy--several methods of ensuring long-term digital preservation have been explored. Learn about the challenges and potential solutions in this article.

Late last year an archivist accidentally discovered hidden within the pages of a Victorian-era scrapbook a rare 12th century edition of the Magna Carta issued by King Edward I, according to reports in the Daily Mail and Smithsonian.com. It is believed to have been placed there by a British Museum official sometime in the late 1800s and forgotten within the city archives of the English town of Sandwich.

Although this copy of one of the world's most famous historical and legal documents is in a battered condition--torn, water-stained, and missing sections--it remains relatively durable and legible; in fact, the document's handwriting, layout, and date (which survives at the bottom) permitted Magna Carta Project historians to verify its authenticity.

The discovery of this rare edition and the Victorian-era scrapbook serves as a timely reminder of the importance of the long-term preservation of information. These physical documents survived because of their paper and inscriptions, which, technically, can be handled, read, and used in much the same way today as in their respective pasts. An individual can still consult and regard each document much as Edward I did more than 700 years ago or the Victorian museum official did more than 100 years ago. Indeed, physical and print materials continue to prove their relative permanence despite technological progress and time's ravages.

The Digital Future

It is doubtful that individuals will be able to engage with today's digitized materials in 10 or 20 years, let alone 100 years, as they still will be able to interact with these centuries-old physical documents. Alarmingly, as more information is digitized, either by migrating physical and print artifacts and resources to online display or, increasingly, by creating it in digital formats rather than print, much of this information may become lost for future generations due to the corrosive phenomenon of bit rot.

Bit rot refers to the irrevocable degradation or loss of digital information when the infrastructure (the hardware and software) required to access, interpret, view, and use this information is no longer available or executable.

As Jeff Rothenberg warned in his seminal 1995 Scientific American article on digitization and preservation, "Ensuring the Longevity of Digital Information," "We are in imminent danger of losing [digital information and documents] even as we create them. We must invest careful thought and significant effort if we are to preserve these documents for the future. If we are unwilling to make this investment, we risk substantial practical loss, as well as the condemnation of our progeny for thoughtlessly consigning to oblivion a unique historical legacy."

Since he raised this warning, the danger has only grown in nature, size, and scope. And it continues to metastasize at an accelerating rate. If left unaddressed and unchecked, bit rot has the potential to wipe out contemporary (and future) history--and sooner than we may realize.

Brief History of Bit Rot

Bit rot is not a new phenomenon; it has been around for decades. In The Discipline of Organizing, Robert J. Glushko describes how "computer data began to be stored on magnetic tape and hard disk drives six decades ago, on floppy disks four decades ago, on CDs three decades ago, on DVDs two decades ago, on solid-state drives half-a-decade ago, and in 'cloud-based' or 'virtual' storage environments in the last decade." Indeed, bit rot's destructive ravages have already begun affecting our information and erasing our recent history.

VHS Tapes and Players

Video home system (VHS) tapes and players, for example, have basically become obsolete technologies. The recorded content and memories on VHS tapes are now becoming, or in many cases have become, lost due to equipment decay and disappearance. It was only about 15 years ago that VHS tapes and players were common technologies in many homes, offices, and schools, used for various purposes, including entertainment, work, and education.

Today, it is more likely to find VHS tapes and players in some kind of museum; even if one happens to have a VHS player and tapes to play on it, most televisions do not support it, lacking the appropriate scart socket feature to take the VHS video input.

CDs, DVDs, and Players

Another example of bit rot involves compact discs (CDs) and CD players. Although not quite "gone" like VHS...