Information Technology Reference
In-Depth Information
Many will already have had the experience of finding a digital object (let's
say for simplicity that this is a file) for which one no longer remembers the
details or for which one no longer has the software one used to use. In the case
of images or documents there is, at the moment, a reasonable chance of finding
some way of viewing them, and that may be perfectly adequate, although one
might for example want to know who the people in a photograph are, or what
language the topic is written in and what the words mean. This would be equiv-
alent to storing a topic or photograph on a shelf and then picking it up after
many years and still being able to view the symbols or images on the page as
before, although the reader may not be able to understand the meaning of those
symbols.
On the other hand many may also have had the experience of finding a spread-
sheet, still being able to view all the numbers, text and formulae, and yet be unable to
remember what the various formulae, cells and columns mean. Thus despite know-
ing the format of the file and having the appropriate software, the information is
essentially lost!
Looking yet further afield, consider the digital record of a cultural heritage site
such as the Taj Mahal measured 10 years ago.
In order to know whether or not visitors have damaged this heritage site one
would need to compare those measurements with current day measurements - which
may have been captured with different instruments or stored in a different way. Thus
one needs to be able to combine data of various types in order to get an answer.
Based on the comparison one may decide that urgent remedial work is needed and
that site visitor numbers should be restricted. However before expending valuable
resources on this there must be confidence that the old data has not been altered, and
that it is indeed what it is claimed to be.
Other complications may arise. For example many digital objects cannot, or at
least should not, be freely distributed. Even photographs taken for some purpose
which has some passers-by in the scene perhaps should not be used without the per-
mission of those passers-by - but that may depend upon the different legal systems
of the country in which the photograph was taken, the country where the photograph
is held and the country in which it is being distributed. As time passes, legal systems
change. Is it possible to determine the legal position easily?
Thinking about another everyday problem - many Web links no longer work.
This will probably get worse over time, yet Web links are often used as an intrinsic
part of virtual collections of things. How will we cope with being unable to locate
what we need, after even a quite short time?
Of course we may deposit our valuable digital objects in what we consider a safe
place. But how do we know that it is indeed safe and can counter the threats noted
above. Indeed what happens when that organisation which provides the “safe” place
loses its funding or is taken-over and changes its name and function, or simply goes
out of business? As a case in point the domain name “casparpreserves.eu”, within
which the CASPAR web site belongs, is owned by the editor of this topic; what will
happen to that domain name in 50 year's time when the DNS registration charge is
no longer being paid?
