In order to provide hierarchical location information, this specification defines two mechanisms, that can be used individual or in combination.
- The hierarchical location Property provides a simple string providing the hierarchical location of an asset. The structure inside the string may expose several levels. How this is exposed, what delimiters are used, etc. is vendor-specific. Examples of such strings are “FactoryA/BuildingC/Floor1” or “Area1-ProcessCell17-Unit4”
- The hierarchical location Objects provide a browsable structure of the hierarchy and simplifies access like getting all assets of one hierarchical location.
In Figure 11, an example is given exposing the hierarchical location by Properties.
Figure 11 – Example of Hierarchical Location using Properties
In Figure 12, an example is given exposing the hierarchical location by Objects. The standardized 0:Locations Object (see 220.127.116.11) is used as entry point.
Figure 12 – Example of Hierarchical Location using Objects
In Figure 13, an example is given combining both approaches.
Figure 13 – Example of Hierarchical Location using Properties and Objects
As shown in the figure, X:Asset0 is referenced by the X:Unit1 of X:Cell4 of X:Area1. The Property HierarchicalLocation provides the same information. As the format of the string is not further defined, it is vendor-specific how to keep both information sources in sync, especially when the Property is writable. Servers may reject Values not represented by Objects or may extend the Locations hierarchy.