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SESSION: NATIONAL SDI II
Distributed Data Management in Internet Map Services
Experiences from Lounaispaikka Thematic Atlas
A. Vasanen1, T. Toivonen2
1Regional Council of Southwest Finland, Turku, Finland
2University of Turku, Turku, Finland
The standardisation work of the Open Geospatial Consortium and ISO has notably increased the possibilities
to build internet map services in a distributed manner. The number of map services offering map data through
standardised interfaces, such as Web Map Service (WMS), has increased particularly in the United States, but
also in Europe. In this paper, we will concentrate on describing the characteristics of distributed data
management in Internet map services using the Finnish Lounaispaikka Thematic Atlas as an example.
The Finnish national geographic information strategy suggests that, as a part of the National Spatial Data
Infrastructure (NSDI), a general map view service should be established to provide users with easy access to
general purpose maps. The service should draw on up-to-date data and underpin public services offered at
national, regional, municipal and local levels (Finnish National... 2004). The view service should be, on the
one hand, an easily accessible Internet service, intended for all citizens. On the other hand, the national
geographic information strategy obligates data providers to set up technical interfaces that can be utilized by
various national as well as regional scale and thematic map services (Finnish National... 2004). The first step
in implementing this strategy will include the development of standardised Web Map Services (WMS)
distributing the core data sets of the main public data providers (Paikkatietoasiain neuvottelukunnan... 2005).
Service Architecture of the Lounaispaikka Thematic Atlas
The preparatory work to create a national network of WMS services was started in early spring 2006.
However, there are already a number of WMS services available in Finland and a number of internet sites
utilising their services. The Lounaispaikka Thematic Atlas covering the region of Southwest Finland is
probably one of the most advanced of these services in terms of distributed data management. The service
utilises virtually all public, non-profit WMS services available in Finland. The Lounaispaikka Thematic Atlas
is the main Internet map server of Lounaispaikka, the regional geographic information service and network in
Southwest Finland.
Currently, the WMS data available through the Lounaispaikka Thematic Atlas consists of three WMS services
providing topographical and geological maps and satellite images (Figure 1).
Fig 1: The service architecture of the Lounaispaikka Thematic Atlas.
As the implementation of the Finnish NSDI proceeds, more and more data content from the Thematic Atlas
map server will be replaced with WMS services, thus increasing the level of distribution. In addition to WMS
services, also distributed database connections are included in the Thematic Atlas. The Ornithological Society
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