SDI Convergence - Nederlandse Commissie voor Geodesie - KNAW

programme. Nevertheless the term 'SDI phenomenon' seems to be a reasonable description
of what has happened in this field over the last fifteen years.
With these considerations in mind this article examines some of the changes that have
taken place in the notion of a SDI during this time. The discussion is divided into five
parts beginning with technological developments and then moving on to institutional
matters. The first of these considers the impacts of innovations in communications and
information technology during this period on the nature of SDIs. The second examines
the changes that have taken place in the conceptualisation of SDIs while the third discusses
the nature of SDI implementation with particular reference to the concepts of
multi level governance that have been developed by political scientists. Underlying a
great deal of this discussion is the notion that SDI development and implementation is
very much a social process of learning by doing. Some of the main features of this
process are examined in the fourth section of the article with reference to the experience
of the State of Victoria in Australia. The concluding section of the article considers
the challenges facing SDI implementation and identifies a number of dilemmas that
have yet to be resolved.
2. THE IMPACT OF INNOVATIONS IN INFORMATION AND COMMUNICATIONS
TECHNOLOGIES
New technologies have played an important role in the evolution of the SDI concept.
The earliest SDIs were conceived before the Internet and the World Wide Web (WWW)
came into being and the opportunities opened up by their development have dramatically
transformed the way that way that data is delivered to users. This was recognised
by the US Mapping Sciences Committee in their report on Distributed Geolibraries (National
Research Council, 1999). In their view, “the WWW has added a new and radically
different dimension to its earlier conception of the NSDI, one that is much more
user oriented, much more effective in maximizing the added value of the nation's
geoinformation assets, and much more cost effective as a data dissemination mechanism.”
The WWW has developed very rapidly over the last few years and the term ‘Web 2.0’
was introduced around 2005 to highlight the changes that had taken place since the
emergence of Web 1.0 in the 90s (O’Reilly, 2005). The most important differences between
the two can be seen from some contrasting examples which illustrate the interactive
and participatory nature of Web 2.0. The Web 1.0 consisted largely of static sites
such as the Encyclopaedia Britannica online whereas the Web 2.0 hosts dynamic sites
such as Wikipedia that are constantly being revised and enlarged by the contributions
from users. Similarly the personal websites that characterised the Web 1.0 have been
replaced by the interactive blogs that are an important feature of the Web 2.0. One of
the standard bearers for Web 1.0 was the Netscape server while Google can be seen
as the standard bearer for Web 2.0. Unlike Netscape, Google began life as a web application
that was delivered as a service with customers paying directly or indirectly to
use that service.
These differences are reflected in the development of the GeoWeb that underpins the
emergence of SDIs. The most important of these from a user perspective have been
summarised in Table 1. From this it can be seen that the GeoWeb 2.0 is essentially
dynamic, participatory, user centric, distributed, loosely coupled and rich in content in
contrast to the static, producer driven and producer centric, centralised and closely
coupled basic content of the GeoWeb 1.0.
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