Data and information are the raw material of the 21st century and public data will therefore play a key role in tomorrow’s cities. The Berlin Open Data Portal daten.berlin.de is the first data portal of its kind in Germany. It provides public data in a structured, machine-readable format and under free license. daten.berlin.de gives companies, organizations and citizens of the modern city a trustworthy access to public data and allows them to process the data for internet based applications and mobile apps.

With 60 on the portal available data sets in 15 categories (status December 10, 2011), Berlin placed an important milestone for the city of tomorrow. Fraunhofer FOKUS has played a decisive role in the conception, implementation and operation of the Berlin Open Data Portal. Therefore a multi-layer architecture was used in order to guarantee an optimal user experience as well as technical sustainability and interoperability. The very heart of the portal is formed by the infrastructure layer that allows the data relevant to the city to be accessed and processed. The software CKAN, short for Comprehensive Knowledge Archive Network, of the Open Knowledge Foundation collects and manages the actual data records. The metadata scheme was developed by Fraunhofer FOKUS and is based on the data exchange format JSON, short for JavaScript Object Notation.

 The starting point for the practical realization of this effort included several elements: a preliminary study by Fraunhofer FOKUS assessing the state of urban data in Berlin, a survey of citizens about the desired data sets and the resulting recommendations for action as well as the Berlin Open Data Agenda. In cooperation with the partners of the Berlin Open Data Portal, Fraunhofer is currently working on the development of additional selected open databases and the provision of the necessary tools for their use and processing. In line with the European Open Cities project, Fraunhoer FOKUS is also working on a data platform for other European major cities.