The linked variations solution is based
upon a user-generated model of the various systems which affect the behavior of the
application under test.
The model for each such system usually reflects its
incremental refinement over time, with either a linear form, or a tree structure sprouting
various nodes, each representing a different version or sub-version. Variations of definitions
can then be linked to version nodes in this tree.
Any number of systems trees may be created for a repository, each modeling
some aspect of an application (or applications) addressed by a project, or an aspect of the
environment (that is, a system or platform, as discussed in the introduction). The most common system to model is an AUT
itself, as it undergoes development.