• The problem of digital preservation

    Date: 21.01.2012 | Category: Access, Digital Preservation, Obsolescence | Tags:

    Paper and ink, with the right care and attention, pretty much lasts forever. Or for 100 odd years at least. The average lifespan of a CD is 10 years. You can do a lot in 10 years…I sprouted a good few inches, passed a load of exams and got a job, but in the grand scheme of things, and certainly to an archivist, 10 years is a drop in the ocean.

    Digital information does not last as long as its paper equivalent, and this is why it is so important to be aware of the limitations from the moment digital material is created. While we are used to 100 year old (and more!) records surviving, we may well have become complacent when it comes to the letters (and indeed blog posts) that we are writing on our computer right now. This problem has been discussed at length by many individuals who are much more well versed than I, but I feel I can at least summarise the problem.

    Digital information requires a third party (be it hardware like a monitor, or software like Microsoft Office) to enable it to be viewed be a human being. Eyes alone no longer cut it unfortunately. The rate of development of software and hardware, means that, potentially within a few years of creation, files cannot be read by either the software or the computer that initially created them. The main options available to someone who encounters this problem are;

    • Preserve the hardware that was used to create the document to allow for it to be viewed over time
    • Run the out of date software on a modern computer using a method known as ‘emulation
    • Convert the file into a more modern file format for use with modern software (more commonly known as ‘migration‘.

    All of these present their own unique issues that would need separate blog posts to go into, but they go some way towards ensuring accessibility of digital material over time.

    I suppose the main defence against digital data loss is simply an awareness and understanding of the issues. Digital items, unlike their paper equivalents, cannot just be placed in a BS5454 compliant storage facility and left to their own devices. Digital preservation is very much an active concern; ignoring items can lead to their irretrievable loss within years (sometimes less) of their creation.

    There are a few simple things that can be done to help slow the state of obsolescence in digital material; these steps can just as easily be taken by Joe Bloggs on his home PC as by John Smith the archivist in a server room of a national organisation.

    1. Make copies…then make some more. Simple but true. Keep several copies of files on several different types of media, preferably in several different physical locations as well, that way, if one fails for whatever reason, you always have a backup. Burning something to disc and then forgetting about it does not constitute a robust preservation strategy.
    2. Check files regularly. Can you still access everything? Does it look the same as it did when you created it? Regular review of material (every 6 months or so) should allow for time to migrate to newer formats if problems arise. Of course, migration of material nearly always results in some form of data loss, but you should be able to preserve what are known as the significant properties of a file using this method (more detail on this is coming in another post).
    3. Label everything. And I don’t just mean with physical labels either, although they’re a good start. You need to find a simple solution to record metadata (data about data) about the items you are looking to preserve. This can be done via a physical label, handwritten paper document or a computer file (preferably a copy on each!) and should record as much detail as possible about the material in question e.g. number of files, types of files, programs required to view the files, sizes of files, a brief description etc. These records could be the only clue that any future user may have to unlocking the information of the media.
    4. Have a process in place. Take some time to think about digital items in your collection. How much material are you likely to be dealing with? How often does it need checking? Are you going to do anything to the files when they reach you to ensure they are recorded properly? Come up with a process for managing items that suits your needs, and make it part of a yearly/6 monthly routine.

    The above list is by no means exhaustive, and I stress, is purely a product of my reading and experience with computers, but these few simple things should go a long way to easing the pain of dealing with digital material.

    This issue has been discussed at length by others – perhaps even a little too much,  to the point where archivists are nervous of the issues and hesitant to learn skills that they may see as  ‘overly technical’. The purpose of this brief post then, is to alleviate some of those fears by suggesting that a few simple steps can make all the difference in dealing with digital materials. These basic steps can form a solid building block for the more complicated elements and help to build confidence in the digital preservation solutions arrived at.