Universal Data Model: A New Standard for Geodata and GIS

A universal data model developed under the auspices of the Czech Chamber of Surveyors (ČKZ), which extends the existing DTM data model to include additional objects and attributes necessary for the collection, transmission, and management of geodata.

Standardization of spatial data using UDM

The data architecture is based on the unified JVF DTM exchange format for regions, which the UDM enriches with elements and characteristics that enable the UDM to record cadastral information not included in the JVF DTM attributes. The main purpose of the UDM is to provide surveyors, GIS specialists, and designers with a unified structure for collecting and transferring data between various spatial data registries or project documentation, thereby eliminating the risk of isolated and mutually incompatible data.

The proposal was developed by the UDM working group led by Jan Floriánek of Hrdlička. Detailed specifications and technical documentation are available on the website of the Czech Chamber of Surveyors in the section dedicated to the Universal Data Model.

UDM functions as a unified data container that enables the transfer of all spatial data, including its attributes, between different entities, ensuring that all participants know exactly what type of information they are receiving. It is primarily a data model for data creators, who are largely licensed surveying engineers.

With the exception of a few basic attributes, the model does not require these to be filled in, nor does it define more complex topological rules governing the parameters of elements or their spatial relationships. These properties can be specified in the UDM, but their definition is left to direct agreement between the contractor and the end user. The UDM defines basic symbology with regard to the appearance of the original CAD records, which, thanks to the Digital Technical Map (DTM), are now obsolete.

Practical Benefits and New Possibilities of UDM

The solution brings tangible improvements to everyday practice:

Compatibility with regional DTMs – the current version 1.1 includes all objects and attributes from the JVF DTM version 1.4.3, ensuring full compatibility with existing structures and enabling automated output generation.

Flexible output formats and easy GIS/CAD conversions – UDM enables collaboration among various entities within a unified structure, thereby reducing errors and misunderstandings regarding attribute data during conversions. It supports seamless data transfer between GIS platforms and CAD systems, such as to DWG format.

The asset management systems in the JVF DTM–UDM cover a broader range of objects, including roads, street furniture, and asset data and area elements not included in the original DTM. Municipalities and technical infrastructure managers can use the model directly to maintain their asset records.

Model attribute extensibility – UDM allows users to add specific object classes as needed for particular projects and includes classes designed specifically for these extension attributes.

Shared symbology – UDM also defines basic data presentation, such as the appearance of lines, areas, and point objects.

More intuitive data presentation – the architecture allows for the inclusion of derived elements such as hatching, text annotations, working layers, and contour lines.

Maximizing the use of data – UDM facilitates sharing and enables broader use of spatial data that has already been collected, thereby significantly increasing its value.

UDM and existing standards

The model builds upon the regional DTMs by adopting their object categories and attribute schema, which it further expands. It is not intended to replace industry standards (such as those of the Railway Administration), but rather serves as a harmonization layer between different systems.

Using software tools, data can be automatically converted into DTM format or other established data models that are compatible with GIS platforms or CAD systems.

Current version and development outlook

The UDM Editorial Board at the Czech Chamber of Surveyors is now responsible for the management and development of the model, ensuring its professional quality and compliance with legal requirements. The UDM working group, led by Jan Floriánek of Hrdlička, is responsible for the entire project.

In July 2025, the first public version without style definitions was published on the ČKZ website. As of November 13, 2025, the complete UDM version 1.1 is available, which includes:

• Complete data structures and their detailed descriptions
• XSD Schemas for Technical Implementation
• Style rules for all content elements of the model
• Complete object catalog, including all JVF DTM 1.4.3 elements

The public comment period will remain open until the end of February 2026. Subsequently, a new version of UDM 2.1 will be created, which will include not only the incorporation of comments but also all changes related to the new version of JVF DTM 1.5, which will take effect on July 1, 2026. UDM version 2.1 will be released in late April or early May 2026.

Standardization, Efficiency, and Openness

A universal data model offers surveyors, GIS specialists, infrastructure owners and managers, and design firms the opportunity to standardize workflows, facilitate information sharing, and minimize data loss during conversions.