background image
223
I X . 5
Th e n e w c h a l l e n g e : B o rn - d i g i t a l re s o u rc e s
The concept of born-digital resources is rather new and reflects the difficulties cultural
heritage institutions face today in managing these new kinds of cultural resources that have
been created with the help of information and communication technologies. Contrary to
analogue resources, archives, libraries and museums can only build on limited experience in
dealing with electronic resources.The most pressing issues related to born-digital material
are on the one hand, their transient, dynamic character and on the other hand, the fact that
the current legal situation does not foresee and allow to properly take care of the exploding
amount of born-digital resources.
As already mentioned, ensuring the integrity of born-digital objects is already con-
ceptually problematic, especially, when it comes to capturing and maintaining resources on
the World Wide Web.Yet another aspect that bears on the integrity of digital cultural objects
is the referencing of digital assets.While memory institutions spend considerable resources
to create means of reference such as bibliographies, catalogues, finding aids, indices,
dictionaries, or directories, the referencing of web resources is only in its infancy.Yet, if users
are to be able to reliably locate digital information resources in a networked environment,
they need a source of reference to consistently discover, identify and retrieve information.
Again, it is especially with born digital material that referencing causes a challenge as
further explained in the following section.
Disappearing web resources
The reality on the web, however, looks differently, as disappearing web resources are the
rule and not the exception. According to estimates, the average lifetime of a web page is just
70 days. (cf. Carley, 1999) There are many reasons why documents disappear from the web,
i.e. the information is no longer of commercial value, the web site has been redesigned
without updating the links, the information in the object has been superseded, or there is
the opinion that there is no longer any public interest in a resource.The result are "broken
links" and "file not found" error messages.
Given the fact, that ever more citations in scholarly papers are actually references to
sources on the web, it is obvious that disappearing information objects are disastrous to the
scholarly community.What is needed is a "web of trust" and the assurance that resources on
the web can be referenced persistently, over longer time periods.
What is emerging in the cultural heritage sector, however, is an awareness that
cataloguing (selected) web resources is a necessity to ensure long-term accessibility of
information objects on the Internet.To do so, what is needed are unique identifiers that
distinguish one digital object from another. Unlike in the analogue world, the use of unique
object identifiers for web resources is not yet common practice.To consistently locate
digital objects in a networked environment, they need to carry at least two identifiers: one
identifier to specify the name and one identifier to specify the location.
Unique identifiers for online resources
For digital resources, these unique identifiers are called Uniform Resource Name
(URN) and Uniform Resource Locator (URL).The URL refers to the specific place
where a digital object resides and is currently the dominant method of object location on
the World Wide Web.The URN, on the other hand, is the unique and permanent name for
a distinct object, which is independent of its current location and can serve as reference,
IX TECHNOLOGY