PDOK is a central distribution platform used for deploying geographical datasets (geo datasets) and making them available as web services and geographical information files. These geo datasets are supplied by government and public administrations. They are therefore guaranteed to be up-to-date, reliable and for free. More than 275 web services are available at the moment. A web service makes it possible for every user to view the geographical data in any available internet browser. These web services are particularly meant to be used by municipalities and other public agencies, businesses, schools and also private citizens. In this way, the Dutch government is stimulating innovation and the (re-)use of geo-information.
The start of the INSPIRE directive in 2007 had an impact on the Netherlands national legislation, which had to be revised in order to meet new international standards surrounding environmental policies. The Dutch Cadastre, was among the early relevant stakeholders, who wanted to develop a central platform only once, that could be used by many, and therefore decreasing the costs. This meant also increase and efficiently sharing of quite rare knowledge. After much discussion and debate, the “Public Services On the Map” (PDOK) was born.
PDOK is a collaboration of the Kadaster, Dutch Ministry of Infrastructure and Environment, Dutch Ministry of Economic Affairs, Rijkswaterstaat (Dutch Road and Water Ways Networks) and Geonovum. Geonovum is a governmental body that develops standards and helps to better exploit governmental geographic information.
By supplying PDOK with their geo datasets, public administrations comply with Dutch and European policies for providing geospatial data from the government. Every public administration that houses geo datasets has to make their data available. PDOK is an available platform but it is not a mandatory one. However, as of late 2016 a significant number of all administrations have joined PDOK.
The PDOK organisation consists of two parts. The functional and technical management is executed by Kadaster Netherlands. It is responsible for delivering the PDOK IT distribution platform and the web- and download services and for supporting the users by providing a Customer Contact Center. The Steering Board is responsible for the control and consists of representatives of all partner organisations. They monitor the quality of service and are responsible for the long term development of PDOK. There is also a Customer Panel, which represents the users of PDOK and acts as a sounding board for customer satisfaction. PDOK is fully open source based and each developed functionality is shared with the community.
PDOK is used by municipalities and other public agencies, businesses, schools and citizens. This can be a GIS expert searching for datasets, services or other geo-information. PDOK is also available for the policy maker who wants to consult a map or for the Geo-IT developer who needs geo information to develop a website or an application. In 2016 the PDOK usage increased to almost 3 billion hits, by far the most used Dutch geo platform.
Since 2016 PDOK delivers some of their data also as high quality linked open data and API's, via a separate platform data.pdok.nl. Doing this, the public open data provided by PDOK can be used more easily by web developers who don't have a geo background. And therefore PDOK highly stimulates use and re-use of governmental data in the Netherlands.
We are not only using open source software ()Postgress, Geonetwork, Geoserver, Geowebcache), we are also co-developers of these tools and active members of the regarding communities.
The Dutch Cadastre, Land Registry and Mapping Agency (Kadaster), Dutch Ministry of Infrastructure and Environment, Dutch Ministry of Economic Affairs, Rijkswaterstaat (Dutch Road and Water Ways Networks) and Geonovum are involved in the governance of the project.
PDOK is based on a service oriented architecture (SOA). This enables PDOK not only to deliver the actual datasets, but also the metadata and web-services, needed in the production processes of its users. To enable and improve the re-use of components and resources, standardization is very effective. In all cases, standards of the Open Geospatial Consortium (OGC) and ISO have been implemented.
The main components are:
- A metadata portal, www.nationaalgeoregister.nl, developed to search, find and deliver metadata about all available spatial datasets and services in the Netherlands. This portal also serves as the INSPIRE metadata catalogue and entry point.
- A central access layer to control the usage of the datasets and services.
- Webservices, complying with international standards of OGC and ISO, enabling interoperable use of the available information. Currently Web Mapping Service (WMS), Web Feature Service (WFS) and Web Map Tile Service (WMTS) are available, while Web Coverage Service is being developed.
- A geocoding service, based on the Open Location Services Interface Standard of OGC.
- Techniques and tooling to extract, transform and load data in the PDOK environment.
- A Geodatastore to upload and download geo open data for free
- An open source Viewer to get an impression of a dataset's content and to combine layers.
- PDOK Map to support easy map creating for a user with existing open data of PDOK.
The solution PDOK is easily extendable. The usage of the webservices has been increased by 600 % in last 3 years, and more increase is expected. The infrastructure is fully scalable, so a temporarily increase of usage can be simply managed by a temporarily increase of the network's capacity, Virtual Machines and databases can be added or removed within hours.
The solution of PDOK is of course used by the official partners of PDOK to deploy their geo data via the PDOK platform, but other partners are re-using this platform as well, like the body of all 24 Waterboards, ProRail (rail infrastructure), Chambre of Commerce, Central Statistics Unit. Those public administrations are using PDOK and have the benefits of not having to develop their own infrastructure.
Regarding the Open Source PDOK is using: Geonetwork functionality that has been developed by PDOK is used within Rijkswaterstaat (Dutch Road and Water Ways Networks) en the Governmental body for Health and Environment (RIVM). The Godatastore software has been re-used as well by RIVM en Rijkswaterstaat.