The RailTopoModel Expert Group is currently working on implementing a One UML Approach for railML3.

Up to now, the RailTopoModel Expert Group designed and enriched the RTM UML model with business objects to fulfil use cases. In parallel railML.org maintains their own railML 3 UML consisting of the same business objects with additional specific features and objects required for the generation of railML3 schema files.

In future the process of a joint UML development aims at concentrating all efforts on one unique UML. With the contribution of a SNCF Réseau driven team (consisting of SNCF's experts, railML.org, Viseo [Integration of Enterprise Architect] and Octo Technology [IT development]), the process and tooling is designed and documented in order to

1. support collaborative work on a unique UML model, and
2. to provide automated generation of the railML3 XSDs.

The railML 3 development done by railML.org will then directly build up on the RailTopoModel foundation. The foundation will be enriched with railML specific UML packages (e.g. Infrastructure, Interlocking, Timetable, Rolling stock). This approach will not only ensure better consistency of RailTopoModel and railML 3but also between railML packages. Duplicate work will be avoided and the development contribution of the railML developing community can be concentrated on specific railway related modelling issues.

Furthermore, this is a step towards M2M (Machine-to-Machine) communication based on web services, which enables IT applications to communicate without human interference (e.g. the foundation for integrated web processes). Following this approach, the French infrastructure manager SNCF Réseau has developed a tool for the automatic generation of Java/C# code from RailTopoModel-railML UML, fully consistent with the railML 3 schema files.