The Interfaces Between Each Class of Simulations Makes Interoperability Difficult
*Blumenthal, Bridging the Grand Canyon, 1997
The traditional hierarchy of models does not work very well. Complex, labor intensive interface processing is required. Although there are software based linkages for connecting dissimilar models this does not guarantee that it is meaningful to do so.
A major problem is the lack of commonality of interfaces due to the use of different earth reference models and coordinate systems. This leads to inconsistent positions and environmental representations.
The lack of commonality is intensified by traditional aggregation policies.
It is much easier, but certainly not pro forma, to interface between entity level simulation classes.
The interface between aggregated constructive simulations and entity level simulations has been referred to as the “Grand Canyon”.*