Alkis® enables a redundancy-free, scale-independent and leaf-free posture of the property cadastral data. The additional storage of meta and quality data, e.g. for up-to-dateness and accuracy, enables the user to assess the technical suitability of the data for its application. All relevant facts and legal states (flours, buildings, owners, etc.) are depicted in ALKIS® object-structured. In addition, all objects receive a lifetime interval. Lost objects are merely historicalised and kept in the database, so that any previous situation can be reconstructed. The modelling of the data structure and the interface NAS (standard-based exchange interface) follows the standards and standards of the International Standardisation Organisation (ISO) and the OpenGIS consortium (OGC).