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e Collaborative work: it has become evident that satisfying
the needs for a large variety of geo-spatial datasets and
services, mostly in near-time mode, is beyond the
capacity of a ‘single’ organisation. As organisation start
to collaborate, they develop a need for new mechanisms.
tools and ideas as to how to define, execute and manage
collaborative processes, [6], [9].
e Interoperable, distributed GIS functionality, the growth of
the Internet and the accompanying advances in
communication technology are pushing the
interoperability efforts to facilitate the sharing and
distributing geodata. Furthermore, these technological
advances are leading to the boom in Web mapping and
Internet GIS. New GIS models emerge, based on the
concept of unbundling functionalities in the current stand-
alone systems to be delivered over the Internet, as
independently developed, yet interoperable autonomous
services, [2], [11].
e Web services: there exists increasing interest in Web Map
Services, as commercially available ready to use services
delivered across the Internet, and the on-going OGC
developments of standards for such services and their
access via standard, interoperable, interfaces, [12].
2.2 The Emerge of ‘Virtual’ Mapping Organization
Geo-information and mapping organisations have been affected
by cconomic and technical developments in the way they
perform their job, creating new ways to do business, being
partnership and collaboration an important business strategy.
This is to satisfy the needs for varieties of geo-spatial data sets
and services, mostly of large volumes and in near-time mode,
and beyond the capacity of single organizations. The
partnership collaboration can be improved by applying a new
business paradigm: the virtual enterprise. By taking this
approach, more tightly integration and communication is
achieved through a common mission, strategy and use of ICT,
with mechanisms to establish clear responsibilities improving
the production relation-ships and thus improving success for the
organisations. The virtual enterprise is a new business practice
that is emerging, [9].
The operational model of such an enterprise is based on the
concept of unbundling of the functionalities of current stand-
alone systems in the traditional Geo-organisations, including
mapping agencies, to make them available as independently
developed, yet interoperable autonomous services. These
functionalities include processes from different data sources,
processes to create databases and manage their access,
processes for map visualisation, GIS functionality for spatial
data analysis, etc. Such services are essentially processes that
run on Web services. Adding to these functionalities, the
commercially available Internet-based services (Web Map
Services), ready to use via standardised access interfaces and
delivered across a wide arca network; the OGC Application
Service provider is an example [12].
An infrastructure, with institutional and technical arrangement
will be required to support the networking and chaining of these
functionalities and services to create customised solutions and
achieve common business goals. Integration is not limited to
data exchange capabilities, but also concern with the rest of the
enterprise by connecting all necessary functions and
heterogeneous functional entities: business processes,
information systems, application packages, organization units,
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B2. Istanbul 2004
resources, etc. The infrastructure will manage information,
processes. control and workflows across the boundaries of the
participating organisations. Basic functionalities and services
are processes that run on Web services, made accessible via
standardised. interoperable, access interfaces. semantic
unification must be assured to support data exchange and need
to be registered in order to be located in a distributed
environment; all these are the main requirements to utilise such
an infrastructure. Further, special services will be developed to
provide the option of combining and chaining of services (a
kind of broker/mediator), also to manage inter-organisational
workflows and manage the quality of services in such wider
network of services, operating under different rules and
constraints, [2], [6]. [9].
3. THE CHANGING ROLE OF GEO-SPATIAL
INFORMATION INFRASTRUCTURE: FROM DATA
TO SERVICE DELIVERY
Geo-information Data Infrastructure (GDI) provides access to
geographical data by networking geo-information databases
ruled by sharing mechanisms, defining technological as well as
organisational aspects for the exchange of data.
The role of the GDI is currently changing, from it being a
simple data discovery and retrieval facility to become an
integrated system suitable for the provision of customised
information and services. For the sake of simplicity we use the
term services to denote geo-information services. Normally
developers address the issue of designing complex services by
stringing together groups of functions in an ad-hoc manner.
This approach may satisfy a particular need but doing this
separately for different services hampers reusability. Moreover,
lack, of descriptions of the solutions obtained makes it hard to
aggregate solutions to execute complex tasks.
From the ‘virtual enterprise’ perspective, a GDI is viewed as a
mechanism that facilitates collaborative work, where it is
possible to link autonomous, distributed. geo-information
centres (data providers, value added service enablers, service
providers and control units) to achieve business goals, [8].[9].
Such a service-centred infrastructure has variously referred to
as the Geog-information Services Infrastructure (GSI).
The objective of our research is therefore focusing on the
development of mechanisms to describe, combine and manage
independent collections of services. Here we introduce a
concept that aims at facilitating the generation of sophisticated
value-added services, (see Figure 1). The idea of the GSI is that
elementary services can be described, accessed, combined and
managed to deliver complex content. Within the GSI a common
method is used to describe elementary services and their
interfaces, and then these services are made available for users
to create service chains that perform complex geo-processing
tasks [6], [7]. [9].
A GSI is a system from which specialised. geo-information
products and services can be obtained by exploiting the
artefacts of an infrastructure of interconnected nodes that
include, among others, data repositories, data brokers, service
providers, service brokers and clients.
