Digital Preservation, Digital Continuity and Digital Sustainability

In my work on digital documentary heritage I often come across three related terms that seem to overlap. As I don’t like conceptual unclarity I analyzed them. I found no overlap but rather a short explanatory story about digital documentary heritage preservation. It answers the What, the Why and the How questions of Digital Preservation:

What?

WHAT do we do with our most relevant digital documents? Answer: we keep them. Digital Preservation is the technical act of keeping records (accessible). Nothing more, nothing less.

Why?

WHY do we keep records? Answer: we keep them because we want our access to them to persist in time. We don’t want loss of digital documentary heritage, we want Digital Continuity.

How?

This question is about the “continuity of Digital Continuity”: HOW continuous do we want our access to preserved digital documents to be and HOW do we ensure that continuity? Answer: by ensuring Digital Sustainability. Digital Sustainability addresses the quality of Digital Continuity. Two examples:

• I ensure the Digital Continuity of this blog text by keeping a Word file on my computer. But how continuous is that continuity? In other words: how sustainable is that preservation solution? That depends inter alia on the willingness of the ICT industry to design future Word versions in such a way that they will still enable me to read my future “antique” Word document. This Digital Sustainability guarantee is what UNESCO’s PERSIST project tries to establish (see my video: https://www.youtube.com/watch?v=L36EbzPnzoM);
• Digital Continuity can be achieved by storing digital documents on servers. But how continuous is that continuity? It’s not as continuous as we probably think. Because compared to the material on which we store most analogue information (paper), the physical infrastructure in which we store digital information is much less sustainable. Not only does it require more and more energy for cooling, it also uses more and more metal coming from declining resources. In fact digitalization doesn’t make information as “dematerialized” and “easy to preserve” as it may seem. It rather refers to a heavy resource depleting rematerialization process, see my recent reminder: http://oosterenvan.blogspot.fr/2016/04/digital-society-are-we-really.html.

This French book about the History of the United States survived 2 centuries already.

What this analysis highlights is that the future of our digital information is fragile. While engraved stones have survived tens of thousands of years, papyrus 3000 years, printed books 200 years and films 100 years, we now have to address the fact that hard discs can crash each time they are used and that CDs have a reliable life span of 5 to 10 years maximum. 

To address this extreme fragility we must ask the right questions about digital preservation. It helps us to define how to do it well: by making the continuity of digital heritage preservation as sustainable as possible.