Core elements

Jump to: navigation, search
This chapter describes the grouping of elements of the model. It also gives a short introduction to the core elements, their characteristics and how to initially build a network.

The RailTopoModel® is described in UML notation. The model is grouped into packages. Each package consists of a collection of tightly coupled modelling concepts. Therefore each package deals with a specific aspect of the model.

Colours in the UML-Diagram

Language Units

The model packages are individually coloured. The meaning of the colours is as following:

  • Base: Grey
    This package contains basic data definitions and also the definition of the network itself.
    Example: The name of the network.
  • Topology: Yellow
    This package contains the topological elements that constitute the network. Topology is implemented by a nodes & edges graph. Nodes are embodied as "NetElement" classes and edges as "Relation" classes. Important: Both classes operate at any level of view.
    Examples: tracks, switches, buffer stops, routes, operational points.
  • Referencing: Green
    This package contains a set of positioning methods for positioning or attaching further elements to the network.
    Examples: Linear positioning (along a relation) or geometric positioning (x, y and z coordinates).
  • Net Entities: Blue
    This package contains further entities that are in association with the network and are not topology elements. These elements are connected to or associated with the network. Each of them has an extent (point, line, area).
    Examples: signals, buildings, tunnels, speed limits.

The complete RailTopoModel® is available at

Building the Model

Model Part 1 (© railML®)

1. First you have to define the fundamental wrapping of your network using a "Network" class.
2. Then you have to determine the topological elements comprising the network – and put them all into a class of type "NetworkResource". Since this class will be used for all view levels, name it something neutral, like "NetElements". According to the view level resp. view levels this will be elements like these:

  • rails tracks, switches, buffer stops, etc. or
  • tracks and operational points, or
  • lines and major operational points or
  • ...

Each of the topological elements must have some basic characteristics:

  • a unique identifier (UUID or any national identifier),
  • a name and
  • a validity range.

What you should have learned

  • You know the different packages of the model.
  • You also know the core elements of a network and how to initially build a network.
Chapter RailTopoModel® Quick Start RailTopoModel® modelling concepts RailTopoModel® External References
Section Connexity graph Core elements Levels of detail